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View Full Version : Sonic Treatment...oh where to start?



AlBurr
01-30-2014, 06:50 PM
So I have been reading quite a bit on the mysterious art of sound treating your studio. There is no end to the YouTube videos describing how to lessen the impact of various sonic disruptions to your audio recordings. It is a fascinating topic that has kept me enthralled for quite awhile and continues to do so.

I love to tinker and DIY stuff always gets my creative juices flowing. There are a number of great DIY videos on how to create very effective sound absorbing panels to hang on your walls and ceiling. I will be building several of these over the course of the next few months. You can easily buy these and pay maybe double what is costs to make them but that's not as satisfying so I will build them...they are pretty darn easy to build. Of course I will attempt to over complicate the process...that's just my style. That will part of another post sometime down the road.

However what I decided to address first was the ambient noise in my office/studio. Currently most of which comes from, you guessed it, my PC. Now in terms of noise it's a pretty quiet PC...that's how I built it...with low noise fans, power supply, GPU fan etc.. I was amazed at how quiet my room was with my PC turned off even though I thought I had a pretty quiet PC.

Interestingly the one area I neglected was the case. I went for the cool factor...much like a lot of people who build there own PCs... So after a bit of investigation I narrowed down my options to sound dampen my case to the following:


An IsoBox http://www.custom-consoles.com/isobox.php

The DIY route and soundproofing my current case with AcoustiPack http://www.acoustiproducts.us/en/acoustipack.asp

Purchasing a purpose built quiet PC case. Several manufacturers make quiet cases, including some of the usual suspects Antec, CoolerMaster, NZXT, Corsair etc. There are however a couple folks who specialize in quiet case design E.G. Fractal, Nofan, Nanoxia etc..



If you really find this stuff interesting there are a couple websites worth a visit namely, Silent PC Review http://www.silentpcreview.com/ and End PCNoise http://www.endpcnoise.com

The IsoBox is very cool but above my current wife aggravation level. The DIY route, though appealing, didn't appear to get me to the level I desired given my current case design. The biggest challenge with designing a silent computer case is balancing the need to cool and the need minimize sound emanation. Fans make noise but they are pretty much necessary for cooling. I say "pretty much" because you can build a completely fanless PC. But that's whole different discussion with regard to components and one you can read about on the two sites previously mentioned.

My choice was to purchase a purpose built case. In my case (pardon the pun) a Fractal Design R2 XL http://www.newegg.com/Product/Product.aspx?Item=N82E16811352029. I decided on this case after a fair bit of review and the fact that NewEgg had it 40 bucks cheaper than Amazon and it was in stock.

So what makes a case quiet?

First limiting the areas where sound case escape. Of course this introduces a conundrum...where does the air come in to cool the components? The answer is by creating pathways that are baffled you can satisfy both requirements, albeit with some compromise.

Second, put sound absorbing materials wherever you can. This was of particular interest to me as I learned a bit about the kinds of materials that work in my earlier research on sound panels to hang on my walls. Some cases used standard foam or egg-crate material which is not very effective. Apparently the best approach is a multi layer system that includes an air barrier or decoupled barrier sandwiched between to different density foam layers. This is what Fractal uses in their case designs.

http://imagizer.imageshack.us/v2/640x480q90/543/w43g.jpg

Lastly are components, Fans, Power supplies (PSU), GPU fans, mechanical hard drives, CD/DVD drives. Most fan manufacturers put dB levels on their boxes...anything under ~18dB is good. There are also manufacturers like Noctua and AcoustiFan that are known for their quiet fans. Most will have multiple sound levels indicated based on the RPM of the fan dictated by the voltage applied. A good PC build will allow you to adjust the speed of the fans so you can tailor it to the task at hand. For example if I were gaming I probably wouldn't care about the noise as I would have my headphones on and my fans on high to provide maximum cooling. However if I am recording I can cut my fan voltages to ~4v which should pretty much render them silent with the trade off being that my CPU might get a bit warmer for a period of time...which is something I can live with. Mechanical hard drives can make real racket...some more than others. There are reviews out there that discuss this. One way to lessen the noise is to reduce vibrations with rubber grommets. They help isolate the drive a absorb the vibrations. Obviously SSDs (solid state drives) are the best option and I can tell you prices have fallen significantly since I last purchased one. I picked up a 480GB drive for under $300 which would have been unheard of a year ago. There are also purpose built power supplies but my current PSU appears to be pretty quiet and I can adjust the fan speed if necessary. Depending on your GPU this can be a real source of significant noise. Again the fans here can be adjusted on some PCs but not all. If you have intensive graphics requirements expect this to be the greatest noisemaker. Personally I can adjust my GPU fan speed to temporarily bring down the noise level when necessary. For CD/DVD drives...well hopefully your not using those while recording...

So in the end was it worth it? Should I just have put my PC in a closet somewhere and done everything remotely? That really wasn't an option for me as I need access to the PC. I'll let you know if it was worth it as soon as I finish the build this weekend. I plan to measure my noise floor (non-scientific method) before and after and will post the results here.

AlBurr
02-07-2014, 08:02 AM
Well I completed the swap out of the cases...was it worth it? I would have to say probably not. My noise floor appears to have dropped about 5-6 dB. However I believe the major source of noise may be a fan. I plan to swap it out this weekend and will measure again. One important note is that my CPU temps have not changed significantly. (averaging 2-3deg C. increase) I was worried given the nature of this new case having fewer ventilation holes.

The adventure continues...