DIY Equiptment Silencer (1 Viewer)

[Chris Tsutsui]

I would like to build a special housing unit for my HTPC that will block out a good deal of fan noise yet still keep it cool.
I was thinking of using some 80mm Panaflo 12L fans externally for the exhaust and intake of the house. In case you don't know, they are 21db loud and are quieter than the L1A fans.
These will be used in addition to my 120mm fan and two 80mm exhaust fans in my pc case. Check out my design idea HERE at the top thumbnail.
The last time I posted this I got nothing but suggestions on how to quiet my PC without having to build a separate enclosure around it but I have scraps of MDF, extra polybatting, and time. If you think you thought of a way to quiet my PC I probably have already tried it without success, I'm running an overclocked (GPU and CPU) system seen HERE.
Any comments on how much this will quiet the PC or alterations of the design welcome as I labeled/colored the pic for identification.
Some numbers I'm dealing with:
Radio Shack SPL meter C weighted Slow response:
56db 1 foot from front of case
60db 1 foot from side of case
Add 3 decibels to those numbers when I turn up the 120mm intake fan to full RPM. Sadly enough, these levels arn't exactly pleasant for me but I've heard far worse.

 

[Alexi]

Why at point (a) do you put the fan so low, and not in the top of the box?
The heat will rise upp, not down.
Why not build the box but skip the extra out fan, put ports on your computer out fans.

/Alexi

 

[Ned]

I use Speedfan to cut the cpu fan speed on my P3 450. With the reduced speed it makes almost no noise. No intake fan in my case, just the PS fan. The fan on the GF2 is inaudible (for now).

 

[Dustin B]

Looks good to me. But I'd move the exhaust fan to where you have the letter a. And I'd move the intake fan to where you have the letter b.

 

[Chris Tsutsui]

"Why at point (a) do you put the fan so low, and not in the top of the box?
The heat will rise upp, not down.
Why not build the box but skip the extra out fan, put ports on your computer out fans."

The point was to get a long duct for the sound to pass through to enable sound dampening. The more bends and the longer the better for sound, but the worse for cooling which is why I thought of adding an external fan to help move air out. I did think about adding tubular extensions but they'd have to be pretty big to allow for damping material to be inserted. I also thought of making a straight through muffler type of extension but it got too ugly and complicated.

Ned, if you looked at my PC mods you'll notice a shiny knob that controls RPM of my primary 120mm fan. It reduces the sound greatly when adjusted yet I still get loud levels. My graphics card is cooled by a huge golden orb that could be overkill but the orb does get pretty hot so I guess it's doing its job.

I think I'll try what Dustin recommends first and I'll take temperature levels. The only thing quieter than that method would be no box fans at all. My room is pretty controlled at 75-80 degrees. Hopefully I won't see too big of a drop in motherboard and cpu temperatures, I guess I'll have to try and find out. If the sound dampening works (which I'm almost certain it will help) I might end up keeping the door open unless I'm critical about listening.

I was thinking of using glass as a window for the door, does anyone know what has better sound prohibiting properties? Glass, Lexan, or Acrylic... I can make it double paned if needed.

Come to think of it, this project seems pretty lame but it's something I want to get out of the way.

 

[Rory Buszka]

Why are you trying to make a quiet box for oyur HTPC? It would be so much easier to quiet down your HTPC itself.
First of all, you want an Alpha Novatech PAL8045 (AMD Socket A/462) or PAL8942 (Intel Socket 478) and you want to put a Papst 8412N/2GL fan on it. These things can be had at http://www.plycon.com/
Second of all, remove all case fans. Use one intake fan (Papst 8412N/2GL) and use your power supply fan as the only exhaust fan. These things will make your PC run so much more quietly, and you will appreciate it. And then you don't have to put it into a big ugly box. Both PAPST fans move about 19 CFM and only put out 12 dBa of sound. People who use these fans are always very impressed. In addition, both fans running at once will only put out 15 dBa together. Then get a Zalman noiseless power supply. You can get those at http://www.directron.com/

 

[Rory Buszka]

Also, what are you doing overclocking a HTPC? Overclock your main computer, but not your HTPC. That just generates so much extra unnecessary heat without super-significant speed gain. And then you have to use big fans to get rid of the sound. You can't have both fast AND quiet unless you go watercooling, and put the radiator in another room or something.