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Noisy House 50 decibel noise

Think this can't happen to you? My new neighbor's house has a heating system that requires two mechanical devices, a ventilation fan and some sort of exhaust pipe. A decibel meter I bought shows a reading of 50 decibels, sometimes noisier. Low cloud cover and rain can actually deflect the noise making it audible in my house. The City of White Rock, BC approved the design but it's made my life a living hell. Sometimes both fan and pipe are in operation and is clearly audible in my house with doors and windows closed. The northwest corner of his home is bowl-shaped so it acts like a speaker and projects the sound as far as 75 yards or more. The noise is now the rule and not the exception. Sometimes it goes for hours on end. It's interesting that the city has allowed it and even though it's a noise problem, they claim they can't do anything about it. The noise is in conflict with the very noise bylaws the city upholds but they still won't do anything. I've asked that a partial shroud or cover be put over it but they can't force the owner to do it. Took my laptop to my doctor to show him the video, his reaction was "they should put a cover over it". If you go to the White Rock City website and do a search for the word "noise", you get a link that takes you to the World Health Organization which stresses how noise can be unhealthy for you. The fan and pipe start and stop all day and night, 365 days a year. My back sundeck is at times unusable because the noise is so ...

Lady Gaga - Bad Romance at Sydney "Monster" Hall. 13 July 2011

THEY came to the Monster Hall last night from all over Australia with their paws up, wigs on and inhibitions gone, inspired by their heroine Lady Gaga. The Pied Piper of pop delivered an entertainment event - Lady Gaga doesn't do mere concerts - at the Sydney Town Hall, and it was all for her fans. Dazzling Versace costumes and a stage built for the occasion were just the icing on the Gaga cake; in the end, all the 800 fans wanted was her. Her every gesture and greeting were rewarded by adoring screams which registered in the upper reaches of the decibel meter. Even Beliebers would have been hard pressed to out-squeal the Little Monsters.

The Art and Craft of Farting

For a little gas, I lost my flourishing career.

My readers who had read my profile would have noticed I am not an admiral and far from the coveted rank. It was all because of gas, a small quantity, at the wrong time and the wrong place.

While I was making a presentation, as a liaison officer for a group of visiting admirals from NATO, it happened at a crucial point. It was not a whimper, but a loud, resounding bang.

The small room full of senior officers, for want of a better expression, stank like hell. I do not know how hell rates on a stink scale, but the room rated close to nine on ten. The disgusted, distinguished dignitaries left the room and country without so much as a by your leave, but with a solemn promise never to visit my country again. One American admiral laughed and before leaving, told me, "You're still a work in progress." My bosses concurred with him and served me the marching orders. I left the navy unceremoniously and made extensive research on the subject as given in the title.

Medical research proves secretion of gas could be due to innumerable reasons, and prevention of its escape is well nigh impossible and not worth attempting. The best proven remedy, of course, is the withdrawal, from the scene of the party or conference or whatever to a place where there would be no one. This, unfortunately, is not always possible and hence the need to look for other options.

Such options should provide any of the following:
(a) to limit the damage,
(b) to deflect the blame to any of the persons nearby,
(c) to get the benefit of the doubt.

Limiting the damage entails:
(a) Suppression of the noise, and if it were not possible, reduction of it to minimum to make it inaudible,
(b) Elimination of the odor, and if it were not possible, reduction of the smell level on a stink scale of ten to less than two.

Suppression of the noise can be achieved by:
(a) Mechanical,
(b) Electronic, or
(c) Explosive methods.

Mechanical method involves using a device similar to the silencer used with pistols or mufflers with the exhausts of ICEs. When the noise level expected is likely to be of higher decibels, the former is recommended. I am pleased to report I have designed a gadget and started production pending the approval of the patent. It is a simple gadget of a number of tubes, one within the other, with a small gap of less than half a millimeter (a few thou in FPS system) between them. The conventional apparatus has a dozen, and the deluxe version has two dozen tubes. The escaping gas passing through the airspaces gets dissipated and muted entirely by the time it passes out at the other end. Designing the instrument and bench tests did not take long, but what proved to be insurmountable problems were: it had to be portable, ready for use when required, and should work for and be acceptable to people of both sexes including the gays.

My team and I have come up with a novel design. The product can be worn by people of all sexes and carried around the waist at the rear. It has a small, soft rubber ball filled with compressed air and is operated by a cord attached to it. The cord goes around the waist and ends up at the front end of the jeans/pants/skirt/dress or whatever. It comes in many colors and easily mixes with the dress of the wearer.

The mechanical device.
When the wearer finds the explosion imminent, he should tug at the cord which releases the compressed air. This makes the gadget heavy, and due to gravity, the apparatus of tubes lying vertically, till then, slides down to take its position to cover the objective- the gap. When it reaches the intended place, a small spring releases to position it a rakish angle. Unless the butt is uneven, the process of sliding will be smooth, and the apparatus gets into position in two seconds flat. It covers the outlet fully and gags any sound altogether. Field trials before the FDA have proved a hundred percent success.

Electronic apparatus.
This consists of an oscillator of adjustable frequency with an amplifier; all miniaturized and contained in a chip. It is worn in the same position as the mechanical device and connected by the same type cord which operates like a switch. When switched on, the device produces a bang much louder than the bang under reference and makes people wonder what exploded in the room. The occupants of the room, unless demented, will look for the cause for explosion and not the perpetrator of the crime. The operation of this device needs certain finesse as the two noises should be synchronized. Otherwise, the results are likely to be disastrous as it will be a double whammy. This has been included in the disclaimer in small print.

An explosive device.
It is a miniature IED. For the uninitiated in terrorism, the acronym stands for Improvised Explosive Device. It is the cheapest of all devices and can be assembled at the house as per requirements of the user following the step by step procedure in the instruction manual written in understandable American English. When assembled, the field tests can be carried out in any open ground, outside the city limits and as far from human habitation as possible. Mountain caves and abandoned shipwrecks are recommended.

It needs to be carried on the person, and at the beginning of any consequential conference or meeting with the boss, it should be placed under the chair. It can be triggered by any cell phone when the situation demands its use, to concur with the noise under reference. In this case also perfect synchronization is necessary. Otherwise, there will be two explosions instead of one. This system has an inherent risk as this device is not taken kindly by security agencies. Discretion of the highest order is essential for use of this device. Further details can be seen in the disclaimer.

Perfume.
This device consists of a small collapsible tube of perfume with a thin membrane as the cover. It can be kept in any trouser/skirt pocket and goes with a needle called Lancelot. When the bang, big or small, occurs, the wearer has to pull a small chord. The Lancelot, cocked like a rifle by a spring, fires the pin which pierces the cover of the tube and releases the perfume within. This scent will snuff out all smells in the room. It will not only spread a delightful fragrance but also work on the grey cells of all persons in an area of five square meters. It will make their feel good factor soar fast. This has no inherent dangers and risks except its exorbitant cost, which is likely to cause high BP. This is specially recommended for people who love garlic with their food.

Psychological.
When the person involved in this unsavory subject under reference is unprepared with any of the gadgets mentioned above, and if the occasion demands it, the psychological method is recommended. When the dramatic event occurs, the best course of action is to look at someone close by as if he were the culprit and a worm unfit to continue in a distinguished company. The potential victim should be selected in advance, if required, by going through his dossier, CV, or medical records, or whatever is accessible. Selection of a wrong individual is fraught with many dangers as the technique is like to boomerang on the user. It is highly likely the intended victim will stare back. In such an eventuality, it is essential to hold one's stare and not blink. Regular practice in front of mirror, for staring for long without blinking is recommended.

Facial expression.
Irrespective of the method employed, it is essential for the perpetrator, this sounds better than farter, to maintain a dead-pan expression on his face. Any sign of regret or remorse is likely to give the game away and confirm the real culprit. Soon many fingers will be pointed at him, and he will meet a fate similar to what I had met.

Lastly, I am glad to inform, thanks to my extensive research supported by data of thousands of persons of each sex and successful field tests lasting more than six months, I managed to get a different prefix and suffix to my name. It was a loss to the navy but a significant gain to the whole world.

I am positive my name has slipped into immortality.

Dr Ramarao PhD.

Buy Cheap Stereo Power Amplifiers

As we all know, amplifier power is measured in watts. If not understood properly, this is commonly a confusing subject. There is a misconception that wattage is directly correlated to the loudness and the volume. Some people even think that by making the power output than normal results to the maximum volume. But the truth is, it has little to do when it comes to the loudness.

However, power output is relevant to the two main issues - which are the ability of the stereo power amplifiers to handle the volume peaks and the speaker efficiency. A music lover knows that music is dynamic, It constantly changes in frequency and level. He prefers stereo power amplifiers in his car because it allows him to understand the dynamic nature of the music he's listening to at its best.

Whether the music be performed live with instruments or in an acoustic setting, it provide the listener with the range that he is looking for. The quiet passages and the loud crescendos are clear. There are also the in-between quiet moments then the loud highlights. It accentuate the dynamic range of the music currently being listened to.

When the same music is reproduced through the cars system, it reproduce the similar range in loudness. Whenever this is played back at the normal volume level, the medium and the soft passages of the music need minimal power. If the receiver had 100 watts of power per channel, like what the stereo power amplifiers have, then the music would be heard better.

For example, a cymbal's clink is heard better in stereo power amplifiers. The receiver uses only a small portion of the maximum output most of the time. This is another reason why music lovers invest in stereo power amplifiers. Finally, speaker efficiency or the speaker sensitivity is measured by the speaker's output that is ranged in the decibels.

For example, the speaker efficiency is measured alongside the microphone. This is placed a meter from the speaker. When one watt of the power is delivered to the speaker and the level meter then measures the volume in decibels. The output level then results to measure the efficiency of the stereo power amplifiers. This makes for good listening which is the main purpose of the music lover for upgrading his car's amplifiers in the first place.

Discover where to buy cheap stereo power amplifiers online. Learn where to buy 2 channel power amplifiers at my site.

Best cheap Extech 407764 30 Decibel to 130 Decibel Type 2 16000 Point Datalogging Sound Level Meter for $612.95 Extech

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Muzzy's Kawasaki Teryx "Whisper Core" Prototype Testing on 2009 Teryx

This video shows using a db meter to test the difference between the stock Muzzy's Kawasaki Teryx Exhaust sound level and the sound level of the Muzzy's Teryx System with the addition of the new soon to be released "Whisper Cores". There is a HUGE difference going from 103.6 to 100.1 db at WOT for the 09 Teryx. Thank you to Muzzy's for allowing me to help test this latest and greatest addition to the Muzzy's line for the Teryx.

Cheap New Hand-Sized VOM Analog Tester Diode overload protected meter Decibel function audio work by Triplett for $148.41 Triplett

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Avalanche 15 XBL2 900 rms sick dub

An old school Avalanche 15D2, sitting in 2.75ft3, getting roughly 900rms, coils in series to maximize BL. Hits 138.6dB consistently on my Ivie meter.

How Is Noise Measuring Equipment Used?

Noise refers to any unwanted sound that is unpleasant to the mind and ears. It is always best to keep the noise levels under control to have a pleasant and peaceful mind. In our daily life, nearly all equipment produce noise, however, noise produced in audio equipment such as microphone, amplifiers and recording systems should be very low.

Recording studios, radio stations and other commercial places use noise measuring equipment for producing good results. There are many types of noise measuring equipment suitable for measuring environmental noise, community noise, music noise, machinery noise, and road vehicle exhaust noise. Some measuring equipment is useful for testing fire alarms, pyrotechnics, and fireworks. While some noise test equipment is used for quality control of engines, gearboxes, axles etc.

Due to the fact that noise contains energy spread over a wide range of frequencies and levels, a simple level meter or voltmeter does not produce useful results instead a special noise-measuring instrument is required. The instruments for measuring noise include sound level meters, noise dosimeters and auxiliary equipment. The sound level meter is a basic instrument which is an electronic instrument consisting of a microphone, an amplifier, various filters, a squaring device, an exponential averager and a read-out calibrated in decibels (dB).

Sound level meters are categorized by their precision a type 0 is the most precise while type 3 is the least precise. In laboratories a type 0 meter is used, while a type 1 meter is used for other precision sound level measurements. Type 2 is the general purpose meter, and type 3 is the survey meter, which is not recommended for industrial use.

Sound level meters have built-in frequency weighting devices that allow most frequencies to pass. The A-weighting network is the most commonly used filter which simulates the response curve of the human ear at moderate listening levels. These meters offer different levels of meter responses to choose from.

The "slow" response comes has a 1-sec time constant, whereas the "fast" response has a 0.125-sec time constant. The "impulse" response has a 35 ms response for the increasing portion of the signal and a 1500 ms time constant for the signal's decay. Results are displayed in the form of a graph on the screen of the measuring equipment. Lately, sound level meters are becoming increasingly small portable devices that can be easily connected to a range of software and via a range of communications options.

For more information on the UK analytical and measuring equipment providers refer to SearchMe4, the UK's leading business directory.

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How to calibrate active subwoofer with studio monitors using spl meter

need an audio file sweeping from 20hz to 20khz - download link at tinyurl.com need spl meter set to slow C-weight if using krk rp5s set level at rear to +6db if using krk 10s set te crossover to 80hz play audio file...at 14 sec u should get a peak db reading on your Spl meter. at 28 sec u should get another peak db reading on your spl meter. (i got my peak levels at 14 sec and 28 sec but your setup could be different, just note the the highest db levels and match them) adjust the volume level of your subwoofer at the rear of it until the first db peak reading matcges the other peak readings.

Uncle Hickory's DWI

My endeavors into family history again brought me to a story of Great Uncle Hickory, the lovable town drunk. Because of his good nature, even when he couldn't remain vertical, everyone liked him. Well, most of the time everyone liked him. Uncle Hickory had one major fault when he was drunk; he liked to sing.

The quality of his voice left much to be desired and he could never hit his pitches. Heck, he couldn't hit anybody's pitches. In fact, calling the warbling sound that emanated from his throat "singing" might be an injustice to the word and an insult to musical people everywhere. His voice ranged from a low bass to a high, falsetto soprano, often on the same aggravating, sustained syllable. Nonetheless, what Uncle Hickory lacked in quality, he made up for in volume.

He could sing loud enough to crack windows, make the church bell vibrate, cause dogs to howl, and drop birds out of the sky. But the biggest problem of all was that he liked to "sing" at two in the morning as he drove up and down Main Street in his old truck. This was long before the days of decibel meters and sound ordinances, and the local police were at a loss as to how they could curb his sleep-depriving revelry.

Drunken driving laws were something just barely being tested in some cities and the desperate people of our small town took the initiative to create one of their own. Thus a remorseful, but unchanged, Uncle Hickory, after one of his late night forays, found himself standing before the judge. The kind judge, who did not live in town and had therefore gotten a good night's sleep, didn't have the heart to lock up lovable Uncle Hickory. He, therefore, impounded Uncle Hickory's truck, thinking that would put an end to the problem of the late night, forte sleep-bandit and, hence, the complaints of the town's residents. Besides, he reasoned, the law was against driving drunk, and, without his old truck, Uncle Hickory couldn't drive.

However, in the early hours of the following morning, the townsfolk, much to their chagrin, heard the same dreadful braying fill the air. Uncle Hickory was dragging Main on his horse and the horse wasn't the one doing the braying. Not long after the sun peeked over the horizon, Uncle Hickory again stood with his court-appointed lawyer to face charges brought by sleepy, irate police officers.

The judge was perplexed. The law clearly stated a person could not drive a vehicle in an inebriated state, but what did that entail? The debate raged for a period between Uncle Hickory's attorney and the prosecution as to whether a horse could be considered a vehicle. To impound one's horse was akin to horse thievery and the judge was not about to get near that - not in the West where the memory of horse rustlers ending up on the short end of a shorter rope swinging from a tree was still recent history. With a stroke of genius, Uncle Hickory's attorney pointed out that Uncle Hickory had been too drunk to be driving.

Thus, Uncle Hickory became one of the first people, and perhaps the only person in history, to have DWI charges dropped on a technicality - having a horse as a designated driver.

More stories, books, and plays by Daris Howard can be read at http://www.darishoward.com
     Daris Howard is an author and playwright who grew up on a farm in rural Idaho. Throughout his life he has associated with many colorful characters including cowboys, farmers, lumberjacks, truck drivers, factory workers, and others while working in these and other industries.

Reducing Noise with Buying a Silent Generator

There is not such thing as a totally silent generator because after all there is an engine that is running and producing electrical power. What does happen is, these manufacturers of power generators will sometimes invest money in designs and materials that help reduce the noise through the engine or with sound dampening products. So when people talk about silent generators, they are really talking about noise reduced generators. There are some really well designed generators with good noise levels.

My first recommendation to people who have never brought a power generator is to ask someone who has one and go around and listen to how it sounds. For really bad designed generators, you can notice the difference at the engine sounds more like a lawnmower and can be very annoying not only to the owners but to the neighbors. If you do not know anyone with a generator, consider a generator with a noise level under 70 dB at 7 meters. This is around the average for many central AC units and should meet most municipal noise pollution laws. A good silent generator should have noise levels around this level or lower using sound dampening techniques.

Silent generators are also great for RV and marine vehicles. Because the vehicles are more enclosed and noise is more of a bother to the individuals in them. No one wants a noisy generator while trying to enjoy a boat ride or camping. A silent generator really solves this problem by lowering the noise level enough to talk over. Onan's MicroQuiet series is a good example offering really low noise levels for RV vehicles. There are a lot of other manufacturers as well that offer either quiet models or special sound shields or additions to lower the overall noise levels of their generators.

Many applications of generators also require quiet noise levels. Many municipalities and home owners associations have rules regarding the amount of noise pollution. These include how long lawn mowers and other noisy tools can be run. The same rules apply to generators and having a noise reduced generator that meets these standards is not only an option but a must. Many parks and other recreational areas have similar noise rules as well and quiet RV or marine generators will insure no problems arise from their use.

Noise is just one of the few considerations when purchasing a generator but is a very important one for not only comfort but to meet any rules or laws.

PoweredGenerators.com is a consumer resource for product research, reviews, functions and uses of electric generators for homes, bussiness and agricultural uses.

Understanding Vacuum Cleaner Specifications

Understanding a large variety of confusing specifications is one of the most challenging aspects of selecting a new vacuum cleaner. First and foremost, consumers want vacuum cleaners that offer the best cleaning ability. And most consumers typically equate cleaning ability with "power" or "suction".

Cleaning ability is not just about power and suction, even though these attributes are important elements of vacuum cleaner performance. With a little information and education, you will be able to sift through the numbers and better understand what the specifications mean and which ones are important to you.

Unfortunately, there is no single rating that indicates cleaning ability. However, there are a number of primary specifications, that when clearly understood, allow consumers to make educated decisions concerning which vacuum cleaner will have the best cleaning ability.

These primary specifications include watts, amps, volts, water lift (or sealed suction), horsepower, air watts, and airflow.

There are also a number of other, secondary specifications that influence cleaning ability that we'll also examine. These include filtration, cleaning tools (agitation), capacity, quality, noise, features and cost.

In order to make sense of all this we first need to understand the basics of how a vacuum cleaner works.

All vacuum cleaners operate based on air flowing from the opening at the cleaning head or tool, through the vacuum cleaner and the bag and/or filter system and then out the exhaust port. This airflow is created by the vacuum motor, which also may be referred to as the suction motor.

The vacuum motor consists of electrical components attached to a fan or multiple fans. When the fans spin, a partial vacuum is created and the pressure inside the vacuum cleaner drops below the ambient (or existing) air pressure in the room. Because air pressure is higher outside the vacuum cleaner than inside, air rushes through the vacuum cleaner.

So, it is easy to see that the vacuum motor is the heart of a vacuum cleaner. After all, the more powerful the motor, the greater the pressure differential and therefore the more suction and airflow, right? And it is for this reason that most of the specifications you see concerning cleaning ability relate either directly or indirectly to the motor.

But here's where it gets tricky. Specifications for components such as the motor do not necessarily relate to the performance of the entire vacuum cleaner, and therefore are only a part of the story.

Let's take a look at the primary specifications one by one:

Watts

The input power of the vacuum motor is measured in watts. Although this specification doesn't take into account the efficiency of the motor, the number of fans or the overall vacuum cleaner design, motor wattage is a valid way to evaluate and compare the power of the motor.

While the ideal comparison is motor input power in watts of Product A compared to motor input power in watts of Product B, some manufacturers do not provide motor input power specifications in the form of watts but instead rate the entire vacuum cleaner in amps. This can make it hard to compare across brands.

However, you can convert amps to watts by the formula, amps x 120 (volts) = watts. Or conversely, you can convert watts to amps by the formula, watts/volts (always 120) = amps. For example, a 1400-watt motor converts to 11.67 amps (1400/120=11.67).

Comparing machines rated in amps with those rated in watts is not an exact comparison because manufacturers that are using watt ratings typically rate the motor only while amperage ratings use the total electrical consumption of the vacuum cleaner including the motor in the power nozzle (the motorized revolving brush cleaning head), light bulb, etc.

This means that a Power Team (a canister vacuum cleaner with a power nozzle) with a specification of 12 amps might be quite comparable to another Power Team with a 1200-watt motor that converts to only 10 amps.

This is because the power nozzle motor consumes 1.5 amps, the bulb uses additional amperage and so on. So, if we subtract the amperage used by the power nozzle motor from our 12 amp machine, we come up with 10.5 amps for the motor and light bulb. In this example, the two motors both have ratings of very close to 10 amps, and therefore, equivalent motor input power.

Therefore, it is best to either compare motor input power in watts of both machines or if you have to compare a machine rated in watts with one rated in amps, try to get the amperage rating of the motor only instead of the entire vacuum cleaner. You can then convert this to watts and have a meaningful comparison.

Amps

A very common vacuum cleaner specification is amps. The amperage rating designates the maximum amount of electrical current used by all of the vacuum cleaner's electrical components when operating. The biggest consumer of electrical current will be the vacuum motor, but the amperage rating includes all of the electrical components, including the vacuum motor, the power nozzle motor, the light bulb, etc.

The maximum amp "draw," (the number of amps the vacuum cleaner uses when running) allowed for any appliance that plugs into a standard household outlet is 12. Therefore, if you see amperage ratings above 12, read the fine print, as they are not true amperage specifications but some other manufacturer developed "performance rating" designed to create the impression of a more powerful vacuum cleaner.

Although amperage refers to electricity consumption and not power or cleaning ability per se, it can be used to compare the input power of one vacuum cleaner to another. This is because while input power is measured in watts, amps are converted into watts by multiplying by volts. Since volts are constant at 120, amps represent a valid comparison of motor input power.

Again, as mentioned above, when making this comparison, try to get the amp rating of the motor only instead of the entire machine.

Therefore, amp ratings give us a means of comparing the input power of a vacuum motor and the vacuum cleaner as a whole and are a meaningful specification for comparison purposes. But again, they are only part of the story. After all, just because a motor or vacuum cleaner consumes more electricity, this does not make it a better cleaner.

The amps specification also does not take into account how efficient the motor is, as well as other design factors, such as whether the motor has one or two fans (two is not necessarily better than one) and the overall efficiency of the vacuum cleaner design.

Voltage

In the United States, standard household current operates at 120 volts at the meter. Voltage within a home is sometimes referred to as "110" and this is because there may be voltage drops through the house wiring. But not to worry, appliances are designed to operate within a range of voltages from 110 to 120.

For the purposes of understanding vacuum cleaner specifications the only thing about voltage we really need to know is the formula, amps x volts = watts and conversely, watts/volts = amps. When doing these calculations use 120 volts for U.S. appliances.

Water Lift (Sealed Suction)

The sealed suction of a vacuum cleaner is measured in inches of water lift. This rating is taken when the motor is totally sealed, and the term refers to how many inches the motor will vertically lift a 1" column of water.

Water lift is what gives a vacuum cleaner the power to pick up or "lift" debris from the floor surface, while airflow then removes it to the dust bag. Vacuum cleaners with more inches of water lift will have an easier time picking up sand and other heavier soils from carpet and flooring.

Water lift is also a measure of a vacuum cleaner's ability to deal with resistance within the vacuum cleaner. This is especially important in HEPA or high filtration vacuum cleaners that have more resistance due to the additional filters that the air has to pass through.

A good water lift rating also indicates that a vacuum cleaner will keep performing at high levels as the dust bag or container fills and the filters "load" or gradually fill with fine particulate and become more and more resistant to air passing through.

The water lift of a vacuum cleaner is another useful indicator of performance in that it is a means of comparing the suction of one motor to another and, generally speaking, the more water lift the better.

Horsepower

This is a rating that was used primarily for marketing purposes and had little or no relation to vacuum cleaner performance in the real world. Thankfully, it has been largely done away with as a vacuum cleaner specification.

Often referred to as "Peak Horsepower" these ratings were obtained by removing the fans from the vacuum motor and subjecting it to the maximum load possible before the motor burned out. Then, a complex formula was applied to come up with a Peak Horsepower rating. Again, this specification is meaningless in terms of evaluating the cleaning ability of a vacuum cleaner.

Air Watts

As we have discussed, typical vacuum power specifications such as watts and amps measure the vacuum cleaner's input power. Central vacuum makers, as well as some other vacuum cleaner manufacturers, have been using the air watts specification to attempt to rate the vacuum cleaner's output rather than input power. Air watts are calculated using the formula, (Air Flow (in CFM) x Vacuum (in inches of water lift))/8.5 = Air Watts.

Once again, there is some question as to whether this is a useful specification or just a new rating to further confuse consumers and make comparisons difficult. After all, when you do the calculations, an air watt comes to 0.9983 watt or just about the same as an ordinary watt.

It is important not to confuse air watts with airflow, the most important specification of all.

Airflow

Airflow is by far the most important specification in terms of determining the cleaning ability of a vacuum cleaner. Measured in cubic feet per minute (CFM), it is the force of this airflow across a surface that picks up the dirt and moves it to the dust bag or container. Therefore, the more airflow, the better the cleaning ability of the vacuum cleaner.

Airflow is an excellent specification because it takes into account both the power of the vacuum motor, which creates suction, as well as the resistance of the bag and filter system that this air must pass through.

Airflow is generally measured through the vacuum cleaner without hose or attachments connected. Because of this, there are several factors that can affect actual airflow, including turbulence in the hose and wands, restrictions on airflow where the cleaning tool meets the floor or other surface, increased resistance due to the bag filling with dirt, as well as filter loading.

Comparing Primary Specifications

In terms of these primary specifications, there are three elements that are useful in comparing vacuum cleaners.

The first comparison is watts to watts motor input power. Ideally, the machines being compared will all have motor input power specified in watts for a simple, direct comparison. If one machine is rated in amps and the other in watts, a conversion of the amps specification to watts makes comparison possible but is "apples to apples" only if the motor amps alone are used for this comparison.

As mentioned in the amps section above, if the only specification available is the amps for the whole machine, a comparison can still be made but it will not be a direct one.

If both machines are rated only in amps, a comparison can be made of the electrical consumption of each unit with an assumption that if these are close or equal, the motors are similar in input power. This is because the motor will be the biggest consumer of the rated amperage.

The second comparison will be water lift (sealed suction). This is a good specification to compare how well the vacuum cleaner will perform as the bag fills and the filters load, and is especially relevant when choosing high filtration or HEPA filtration vacuum cleaners. It also provides some idea of how vacuum cleaners compare in terms of picking up heavier soils such as sand, grit and so on.

The third point of comparison is airflow. This is the most important specification of all when choosing a vacuum cleaner because airflow is what moves the dirt from surfaces to the dust bag or container. In short, airflow is the best specification that demonstrates cleaning ability.

So, now with airflow rated in CFM and water lift rated in inches, what types of numbers should you be looking for? On canister vacuum cleaners (with or without power heads) airflow of 100 CFM or more and water lift of 90 inches or more is recommended.

Upright vacuum cleaners come in a wide variety of configurations, but there are two basic designs. The first is the "Direct Air" or "Dirty Air" design where the dirt passes through the motor prior to any filtration en route to the dust bag. Dirty air uprights are only rated in amps.

The second basic design is one that features a by-pass motor where unfiltered air does not go through the motor. In uprights with this design, only filtered or completely clean room air passes through the motor in order to cool it. By-pass uprights will usually provide airflow but not water lift specifications and a high performing upright will offer 60 CFM or better.

There is no need for water lift ratings on both types of uprights, because there is so little distance for the air and soil to travel. CFM ratings do not have to be as high as canisters for the same reason.

Many uprights will not offer airflow ratings at all and will only rate the motor in terms of amps. As we have learned, this only measures the electrical consumption of the motor, which is not a measure of cleaning ability. Still, when comparing different vacuum cleaners of this type, amp ratings are better than nothing.

When you choose a vacuum cleaner with excellent airflow and water lift specifications, you are well on your way to a machine with outstanding cleaning ability.

Secondary Specifications

We have examined the primary specifications that impact cleaning ability. But there are also secondary specifications that should be considered before making a final decision. These include filtration, cleaning tools (agitation), capacity, quality, noise, features and cost.

Filtration

Filtration is very important in terms of cleaning ability because HEPA or other advanced filtration increases the resistance within the vacuum cleaner. Therefore, it is easier for a vacuum cleaner with normal filtration to accomplish higher airflow ratings. In fact, the challenge of coping with higher resistance is one of the reasons that HEPA filtration vacuum cleaners can cost more.

For more information on HEPA filtration vacuum cleaners, click here.

The dust bag is also part of the filtration system and a significant factor influencing airflow. Many new materials, as opposed to traditional paper, are being used to manufacture dust bags in order to retain the fine dirt and harmful small particles while still allowing air to flow as freely as possible.

The surface area of the dust bag is also a factor because the more surface area the bag has, the more easily the air will flow through it. This translates to better cleaning ability as the bag fills. This is a good reason to choose full sized vacuum cleaners versus medium or compact ones.

Cleaning Tools (Agitation)

The primary cleaning tool must be correctly selected because while airflow is what transports those soils to the dust bag, agitation is what dislodges soil from carpeting, flooring and other surfaces.

Therefore, explore the type of cleaning tools that make sense for your home. If you have lots of carpet or difficult soils such as pet hair, choose an upright or a power team with a motorized power nozzle. If you have furniture that is difficult to get under, be sure your vacuum cleaner has a low enough profile cleaning nozzle to reach these areas and so on.

If you have a vacuum cleaner with all the airflow in the world but an inadequate cleaning tool, results will be less than optimal.

Capacity

The capacity of your vacuum cleaner has a role in terms of maintaining high levels of cleaning ability. As we saw above, the larger the dust bag, the better the airflow, and therefore, cleaning ability. All other things being equal, a full-sized vacuum cleaner will offer better cleaning ability, especially as the dust bag or container fills.

Quality

The quality of your vacuum cleaner is also important. You can have excellent specifications in a poorly constructed vacuum cleaner that will last only a few years, compared to extremely high quality products that will deliver outstanding cleaning performance and will last many years and even decades.

Quality can be partially determined by the length of the warranty as well as the type of materials used, the quality of the fit and finish, how heavy duty the housings are, how tight the seals, how close the tolerances and so on. Generally, mass-market, low-priced products are not designed for long-term use.

Noise

Noise is also a significant consideration. Some vacuum cleaners can be so noisy that they're almost unbearable to use. A high-quality vacuum cleaner will often operate at levels that are quite comfortable and will allow you to hear the phone or doorbell ring quite easily.

The amount of noise a vacuum makes while operating is rated in decibels (dB). To give you some idea, a conversation at home is rated at 50dB, a garbage disposal at 80 dB and a motorcycle or lawnmower at 100 dB. Extremely quiet vacuum cleaners can operate at decibel levels in the mid-sixties while cleaners in the 70-77 dB range are still very quiet compared to the vacuum cleaner you grew up with.

Features

Next, you need to consider whether the vacuum cleaner you're considering has all or most of the features that you need for effective and pleasant cleaning.

Consider your cleaning situation and be sure that the vacuum cleaner you choose gives you everything to make the chore of vacuuming as easy as possible. Does it feature a cord rewind, variable speed controls, on-board tool storage, height adjustable wands, an adequate cleaning radius, the proper tools for your flooring such as a soft brush for your slate entry tiles and so on.

Cost

And, last but not least, you need a vacuum cleaner that represents the very best value. As with everything, better quality usually costs a bit more, but is often worth it in the long run.

The idea of Best Vacuum began when Paul Teven was working for various Chicago-area appliance stores as a vacuum cleaner repair technician. In 1983 Paul opened his first vacuum store in Chicago. In 1995, Best Vacuum became one of the first brick-and-mortar stores to open a Web store.

Drumster part 3

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How to Build a Recording Studio

Studio Considerations

The magic of the recording studio has often mystified even the most seasoned professionals. With all the knobs, switches and buttons on various gear and large format consoles, no wonder confusion sets in to most non-techies. Many people, especially artists, composers, producers, and engineers, will end up putting together their own studio for writing and pre-production, with some eventually deciding to take the plunge and create a full-fledged recording complex that is capable of recording major albums. This article will try to shed some light on the considerations to take into account when making a studio, be it a small home studio or a professional recording studio.

Is size important? Some may say it is so but this is not always the case. The dimensions of the studio are very important. A room too large may become over-reverberant or full of unwanted echoes. A room too small may sound tight and unnatural. It is important that the room size and room sound is relevant to the type of music you are recording. You don't want to go into a very small tight room to record BIG rock drums. Although, big room sounds can be achieved by adding external reverb effects to simulate rooms at a later time when necessary.

It is best to find the room that suits the sound you are trying to achieve from the beginning of the recording process. The smaller the room, the smaller and tighter the sound will be; this is not necessarily a bad thing. Small tight rooms can be good for vocals, guitars and percussion if you are going for a tight clean sound. Larger rooms have more air for the sound to travel in, so it will be in fact a bigger more open sound. The sound has a longer travel time for the sound wave to move, therefore the reflection from the walls will take longer to bounce back creating a bigger more spacious sound. The decision of size and sound has to be made early on before the recording starts. One advantage that a larger room will have is the ability to be scaled down by closing up the room using modular baffles or gobos (go betweens). Gobos are structures that are partitions, that help to block sound by placing them in between the musicians, instruments, and microphones. Placing the gobos around the microphone at a close distance will help a large room with too much ambiance sound smaller. This will eliminate the reflections coming off of the walls that are further away.

Small rooms can produce big heavy tight sounds with the absence of the decay from the reverb that is caused from big rooms. Sometimes a large room can sound like it's washed out, or far away. With a good engineer any room can sound amazing with a little adjusting. A poor sounding room can be manipulated to sound good, although it requires much more work and time. Deciding on the proper room size for your needs is critical to the sounds that get re-produced. This will highly dictate the type of sound the microphones will pick up.

Clapping your hands in a room can give a good representation of what a room will sound like. The reflection coming off the walls will be picked up by a simple hand clap. The true test is to try out some instruments or vocals and position them in various sections of the room until reaching the optimum sound quality. If one side of the room sounds bad try a different spot or move around into a corner until the sound is improved.

Experimenting with different sections of the room also keeps the sound fresh when recording many instruments. If the acoustic guitars are recorded in the center of the room, when the time comes to record the electric guitars you may try recording them in a corner of the room for a different room sound. This gives clarity on the final mix creating separation and providing more distinction on various sounds.

If you are starting your own studio, remember that the bigger the studio the higher amount the bills will be. The benefit is that larger studios can charge more for their studio rates.

Getting the Necessities

If you happen to reach that elite 2% and become that million dollar, hit selling, famous producer or artist (or if you just win the lotto), then you might eventually think about buying serious studio gear and setting up your own producer paradise.

Acquiring the proper equipment and labor is key to a great studio and successful recordings. Studio gear is expensive and the knowledge of those who use the gear does not come cheap. Hiring the right people can save money and time in the long run. Studio designers also are specialty breeds that can make or break your studio. Your buddy Joe the carpenter may be able to help build it for less, yet if the studio is not properly isolated for sound it is a great waste of time, energy and finances.

The studio engineer is also the focal point of the sound that is created. Having an experienced engineer involved in the process will make your sound have a character of its own. He is the extra set of ears that gives another dimension to your productions. He is also a critical consulting partner when building or choosing to rent a studio. Let the experts help you with advice, it will create less of a headache in the long run. The experienced engineer can fill you in on all the equipment needed for recording the music that is relevant to your world. He can also give some guidelines on how the studio should be setup before having to consult a designer. There is no room for guessing or assumption on these issues.

Check List: Part 1

When purchasing studio gear it is wise to research only what is absolutely essential for your style of music. If you're not recording live drums in your studio, there is no need to buy a plethora of microphones for them. By being patient and shopping around for the best prices, a mass amount of money can be saved in the end. When you save $50 to $100 bucks on each piece of gear it really adds up in the end, and there is a ton of gear needed to put a proper studio together.

Below is a basic studio checklist that will be discussed in further detail in later articles. These are the essentials of modern day recordings and the tools that are most commonly used in the best studios around the world.

The Studio Gear Checklist:

Recording / Mixing Console

The engineer or producer operates the console that controls all of the levels for recording, playback and mixing.

This is the big board that has all the buttons, switches, knobs, faders which control the levels and signal routing for each instrument. This could be referred to as a board, console or mixer. The most common consoles in major studios are SSL (Solid State Logic) or Neve. The console is the most important piece of gear in the studio. It controls the overall operations of signal flow and sound manipulation. The console allows for each instrument to be on its own channel on the board. Each channel may then have effects inserted into its signal path to enhance the sound. A signal may also be routed to external gear for further manipulation. Anything that can be imagined, can be done. There are no rules for experimenting with sound. A signal can be sent to reverbs, delays, compressors, guitar amps, speakers in hallways for re-recording

Each channel strip on a decent console will contain: Faders, Preamps, Panning, Equalization, Filters, a Routing Matrix, AUX Sends and Returns, Dynamics, Muting, & Solo.

Other Features Of The Console: Inserts, Outputs, Monitoring, Automation, Fader Grouping, Bussing, Splitting...

Patchbay

Allows the studio to combine interconnectivity with all the equipment by using patch cables. The patchbay can be configured for each studio's specific equipment requirements. All of the outboard gear, console and recording devices inputs and outputs are hard wired to the patchbay. The Patchbays can be be analog or digital. The most common is the bantam TT cable configurations.

Check List Part 2:

Microphones Microphones pickup the initial sound source. The mic is the first source in the recording process receiving and converting the sound wave into electrical energy to be amplified, transmitted and recorded.

Preamps Amplifies the original signal coming from the mic or instrument. Gives initial control of the recording levels. Preamps are located on the console or as external outboard gear.

DI Boxes The Direct box is used mainly for instruments such as keys and bass to be compatible with mic inputs. The DI box transforms line levels of instruments to mic level for console and preamp inputs.

Compressors Helps to further control levels and dynamics coming from the preamp or console. Usually comes in rack mounted outboard gear or software plugins for DAWs. Compressors keep levels from peaking into distortion levels and help to bring lower levels louder.

FX Processors For special effects like adding space, dimension, pitch and time delays on signals and recorded tracks. Usually comes in rack mounted outboard gear or software plugins for DAWs. Multi-FX processors may have reverb, delay, flangers, EQ, compression and more all in one unit.

FX Pedals Small floor foot pedals originally designed for guitar FX processing. These pedals are created for distortion and special effects, which add space, dimension, pitch and time on guitars mainly, but are an inexpensive alternative used as outboard gear for other instruments.

DAW The Digital Audio Workstation is like an entire studio inside of a computer. Protools, Logic and Nuendo are just a few DAWs that provide a digital multi-track recorder, a virtual console, a wide variety of effects, editing, and sequencing(musical programming) possibilities. The DAW uses software, hardware and computers in combination to operate.

Check List: Part 3

Control Surface The control surface acts as a console that controls a DAW or external machine. The control surface usually has faders, knobs and buttons that are controlled by the computer connected to a DAW. This makes operating the DAW similar to analog operations by being able to put your hands on faders instead of clicking a mouse. Some control surfaces have all the same features as a console. The most common control surfaces are made by Digidesign.

Clocking Digital recorders use different clocking formats to operate properly. Digital units sample the sound to be replicated. Clocking refers to the amount of time in between samples taken for reproduction. If the digital clocking is off it will sound jittery or add noise to the sound in the analog to digital conversion. A quality clock will improve the sound. Some common digital clock sources can be found in products made by Prism, Rosendahl, DCS, and Aardsync to name a few. Some clocks have sync generators built in to lock up with other machines.

Sync Generator Generates tones to allow communication between machines so that several recording devices can be synchronized together and operate at the same speed. Clocking works with synchronization (sync) when analog and digital equipment is combined. Sync uses SMPTE, MTC (midi time code), Midi Clock, MMC (midi machine control) to allow recording on several DAWs and tape machines to be linked up together.

CD Recorder Records and plays back compact discs. Gives the ability to record stereo mixes and playback these mixes on other CD players. CD standard for consumer playback is a sample rate of 16 bit and a sampling rate of 44.1kHz. Sony, Tascam, Alesis, and Yamaha all make good studio CD recorders.

Tape Machines Recording machines that use analog or digital tape for recording and playback of music. Some purists in sound recording prefer the sound of analog tape. There are many digital tape machines used for recording both music and video.

Cabling Literally miles of various cabling could be needed for a single studio. Common cables in sound reproduction are XLR balanced mic cables and Unbalanced 1/4 inch instrument cables.

Monitors / Amps Speakers in the studio are referred to as Monitors. Powerful clean amps are needed to run monitors. Many monitors are self powered, which means that they have built in amplifiers. Monitors usually consist of high frequency tweeters, low frequency woofers and cabinets that contain the speakers and components.

Headphones / Distribution By using a set of earphones this allows communication between the control room and the studio, also allows pre-recorded tracks to be heard during the overdubbing process. Headphones are also referred to as cans.

Instruments / Keyboards / Drums / Guitars These are more of the tools of the craft. You may have all the best studio gear in the world, but if the instruments sound bad you are starting in the wrong place. Anything could be considered an instrument if it makes noise that could possibly be recorded on a record.

Amplifiers This is often referred to as an amp. Amps increase the amplitude or volume of electrical signals from sound waves. These are used in powering speakers. Guitar and Bass amps can be used for many other applications such as running a vocal or snare drum through them.

Microphone Stands A wide variety of sizes and styles are needed for a proper studio. The mic stand helps to get the microphone placed properly for the best sound quality possible.

Studio Furniture There are many types of racks and furniture designed to hold consoles and outboard gear. The interior decoration of the studio completely sets the vibe of the working environment.

Electricity

Nothing will work without electricity unless you're jamming at the local drum circles down on the beach. Electrical installation studio power is often overlooked. Studios will setup a "clean feed" that is a separate breaker from the rest of the general power that is being used for air conditioning, lighting and the basic necessities of the rest of the building. Have you ever plugged something in and heard that horrific buzzing sound coming from the speakers or guitar amp? This is usually due to bad electrical wiring, which causes ground noise. This is the first thing to listen for when going in to a studio session. A simple solution to the problem would be to use a simple ground lifter on the gear or lift the ground from a direct box which can also solve the problems. We will go into details later.

Isolated electrical circuits for each individual room are a must in a recording studio. The proper amount of amperage is also a must. Not enough amperage will surely cause your breakers to blow. Consult with an Electrician who is familiar with studio setups to insure that wiring and voltage is regulated and conforming with local codes.

Unregulated Power Supplies (UPS) should also be in place just in case there is a power failure. This will insure that valuable equipment will not blow up or cause a fire. If there is a case of a power outage the UPS will provide enough time to backup important computer files and safely turn off your equipment. Some studios will have complete generator systems in place to keep the studio running for the remainder of the session.

Improper lighting can also cause buzzing ground issues, especially fluorescent bulbs. Avoid using these in any studio. Dimmers can also cause many problems. The average household dimmers will surely put a damper into a clean sound. Make sure that professional grade dimmers are installed to avoid ground noise. Always listen carefully to signals being recorded before committing to a final take. There are a countless number of accounts that the engineer discovers electrical noise on takes during the mix process.

If you are serious about your studio, may I suggest balance power or a separated panel with neutral power conditioning. The evil problems of ground issues are a direct reflection of sources returning or looking for a different ground. Voltage potential between neutral and ground will certainly change your way of looking at things... for example, .5 volts between neutral and ground is the maximum allowance by UL code that electronics will operate optimally without potential induction issues. I would suggest having a meter installed to rate this. Logging this information and having a good rapport with the local electric company would not hurt at all.

Air Conditioning/HVAC

This is another very important area that is often not considered. Studio gear gets very hot. The lack of adequate cooling could result in equipment failure or damage. Blowing up equipment is no fun and it gets very expensive. Some recording studios have a separate Machine Room for computers, tape machines and power amps that is highly air-conditioned to keep everything cool. This also cuts down on the noise from the fans on such units, which can distract concentration from listening in detail in the control room. Having too much air conditioning could also result in moisture or condensation build-up that may also damage the gear. Water in general is bad for electronic gear.

The return air system is used to pull heat out of needed areas and also provides an air intake for the AC units. These are placed in key areas where there is a build-up of heat from the gear, for example near the console or in the machine room.

Separate Rooms: Control Room

Most studios have several isolated areas for recording, mixing, and production. Soundproofing is the main agenda when creating multiple rooms in a studio. To achieve this, the main objective is to make the rooms airtight. If air cannot leak in or out of a room, there will be less chance of sound leaking in or out as well.

Most pro studios have double doors that create a sound lock to help prevent noise leakage. They also have very thick double walls with interior air gaps to also help trap unwanted sound. The floors in the studio should also be floated which means they are lifted from the ground to help further prevent extra vibrations and leakage.

The first focus would be the Control Room where the mixing console and outboard gear are contained. This is where all of the recording and mixing is controlled, hence control room. The acoustics in this room should be designed for hearing the exact sound that is being recorded or mixed. The sound of the room should be as natural as possible for accurate representation of the original sound translated to the speakers in the room.

The first rule for an appropriate acoustically treated room is that there should be no parallel walls .If you were to clap your hands in a room with hard parallel walls you would here the sound bouncing back and forth, this is known as a flutter echo. This is neither good for recording or mixing. The trapping of unwanted bass is important for a room to sound great as well. Twenty five percent of the room should be assigned for bass traps for an adequate mixing room.

Separate Rooms: Live Rooms

The next focus of equal importance would be the Live Room where the music is recorded. This is where the musicians and vocalists perform on the microphones. Live rooms should have more versatility to be able to adapt to different recording situations. Wood floors for example are great for reflection of sound, which creates a brighter tone. If a warmer tone is wanted, one could simply place a rug on the floor. Many live rooms also have a great deal of glass to see between rooms for communication. This is also very reflective. Many studios use curtains to control the amount of reflections coming off glass or hard walls. Non-parallel walls are again needed to eliminate any flutter echoes.

Some studios also contain a vocal booth within the live room. This would be a smaller room designed for vocals. They may also be used for guitar amps and other instruments. There are no rules for what this can be used for; its main purpose is for additional isolation during the recording process. Glass doors or windows are used for visibility of the artists and those working in the control room.

Many elaborate studios may have multiple control rooms and production suites. Lounges and proper bathroom facilities are important in keeping the creativity flowing. A dining area and kitchen are also a consideration if budgets permit. Many hours are spent in the studio when working on projects. It is important to have all the comforts of home to keep everyone happy.

A few proper offices are necessary for the client to be able to have private internet access and to handle business without any distractions. All studios are designed differently. Whatever can be imagined can be created. There are no rules, only guidelines.

Acoustics

Sound is a wave, much like the ripples on a still body of water when a rock is dropped into it. The larger the wave, the lower the tone. Lower tones, known as bass frequencies, travel in wide long waves while higher tones known as treble frequencies travel in a tighter, shorter wave. Frequencies heard by the human ear range from 20Hz to 20K. Just as an indication, a piano's range, probably the widest range of any instrument, is from 39Hz on the low note and 3Khz on the high note.

Sound is measured in decibels also represented as dB. An average concert is about 95-100 dB while a heavy rock concert or hip hop concert could reach levels of 130dB. This is above the threshold of pain; so don't forget to wear your earplugs which are designed to protect your hearing when in extreme sound levels. Interestingly enough, whales can actually produce levels of up to 180dB. It should be remembered that taking care of your ears is the most important thing you can do to prevent damage and have a sustained career. So don't hang out with any whales and put some protection in your ears when exposed to loud volumes.

Absorption is the act of a sound wave being soaked up by a particular material. This is measured by co-efficient ratings. The higher the sound absorption co-efficient rating, the more sound that is being eliminated from troubled spots in your room. Different section of the room may require different co-efficient ratings. Remember that studios start off as an empty shell. Hard surfaces and walls need treatment to provide for a great sounding room. For example, 20 gauge theater curtains are commonly used in studios. They consist of a thick velvet material, which is excellent for absorbing high-end frequencies. The thinner materials soak up higher frequencies.

The thicker materials soak up lower frequencies. This is why thick bass traps are very large and contain ports or holes to trap low-end frequencies. The larger the port, the lower the frequency absorption.

There are endless amounts of products and designs that are used in the industry. Wall panels are also commonly used to absorb sound. These are made from a fiberglass product wrapped in a cloth material. Various sizes and thickness are used for problem frequencies. Again the thin materials eliminate high end and thicker materials absorb low end.

Reflection is the opposite of absorption. Think of the sound as a wave hitting a mirror and bouncing back. This can be used as an advantage for a brighter tone. If a room has too much absorption causing the room to sound too dead, hard surfaces such as wood panels can be placed in strategic locations to add a more live sound to the room.

Some studios have reversible hanging panels that can be flipped between reflective and absorptive to change the room sound at will. For vocals the room may need a more dead sounding absorptive room. Drums may require a more live sounding room. John Bonham, from Led Zeppelin had an amazingly huge live reflective drum sound. This became the goal for the big Rock drum sound.

Prince is underestimated as a drummer. He has a great tight drum sound on his first record where he played all of the instruments as well as the drums. The drums have just the opposite effect using absorption in a small tight room creating a very in your face heavy Pop drum sound.

These are not rules, only guidelines. Using your ears is always the key to getting the best sound.

Designing a studio is quite an undertaking to do professionally. Each room is completely separated and isolated from one another. The most common method is to actually build a room inside of a room. The inner walls do not touch the outer walls, which creates an air gap that traps sound. Each wall can be many feet thick and multiple layers of thick glass and doors divide the rooms.

The floors in each room are floated from the ground with spacers that also create an air space to lower vibrations and help to trap unwanted sound leakage. All floors have different characteristics in the way sound waves bounce off from their surfaces. While wood floors have a warm tone, concrete and tile have a brighter tone. This also holds true for walls.

A solid plan is needed to run cabling between rooms so that each room can be interconnected with each other for microphone signal lines and headphone communication systems. Custom made cable troughs or PVC tubing is used to send groups of microphone cables from a panel to the control room. From the control room the Headphone lines would be run through the walls for communication between all of the rooms.

Materials and Tools

Drywall is needed for walls. The more layers of drywall added will increase the thickness of the studio walls. By using varying thicknesses of drywall stacked and shifted, alternating at the seams will help minimize sound transmission between rooms. Many drywall screws and a good electric drill will definitely come in handy if you are building a studio.

Fabric is used for making wall panels and ceiling clouds that control the absorption in the studio. There are specific fabrics that are designed for different frequency absorption. Each thickness and texture has varying co-efficient ratings at multiple frequency bands.

AC Duct Board and other fiberglass products are wrapped in fabric with spray glue to create absorbing panels called Wall Boxes and Bass Traps. Thermal Fiber or Fiberglass Insulation is inserted in between two sets of walls and ceiling to create an additional thickness providing an alternate texture, containing fiberglass, which is superb for capturing sound.

Sand is also an excellent alternative choice for filling walls to prevent sound wave transmission. Wood provides the skeleton for frames that hold the panels and boxes. Larger Bass Traps with large ports could be made from wood or fiberglass. RPG panels are a series of wooden slats mathematically designed to absorb and refract, or soak up and scatter sound inside a room. Wood can also be used to create custom racks to hold the outboard gear, console and patchbay. Custom studios can be designed for any situation and style.

Doors, Walls and Windows

Doors and walls are the single most important item where recording studio sound bleed is concerned. A small 1/4inch air gap at the bottom threshold of a door will release 30% of the sound. Creating airtight rooms are the first step in sealing all the gaps for optimum sound proofing. The transitions between where the rooms are connected have more possibilities for sound leakage. All corners, gaps and frames for door and window cutaways must be sealed with a silicon or caulking material. Keep in mind that if air can escape through any passage then sound will surely go through as well.

Sarit Bruno manages content and editorial line for Audiofanzine

AudioFanzine offers benchmark testing/reviews of products, software or instruments and articles of a tutorial nature, all of which are systematically illustrated by exclusive videos or audio extracts. Addressing a universal audience, both amateurs and professionals alike, http://Audiofanzine.com addresses musicians as well as sound engineers, home-studio recording enthusiasts, and audio and lighting engineers.