Cheap, Clean, Cool and Quiet Case Cooling

Actually, most of it is semi-old news to SPCR regulars, but nevertheless a good starting point for newcomers.

7 fans?

I wonder how he got his sound measurements ?!?!

...And I can't quite make out the PSU, but it must be a fixed speed version and the author's obviously not concerned about feeding it a steady supply of 40°C+ air.

You certainly gotta give him Brownie Points for his thought and effort though.

Brownie points -- is that good, bad, or ironic?

"Brownie Points" is good. IIRC, Brownies are pre-Girl Scouts and they earned these points for doing good stuff. Anyone that can help fill in the details, you're welcome to it...

Staying off the topic -- interesting about the origin of brownie points (I'm a linguist and a translator, so I'm supposed to be). The reason I asked was that I thought it might be a derivation of "brown nosing", which would make your comment really sarcastic...

While the article does have some good points, the author obviously doesnt know much about sound measurement, seeing as he noted that a 16dB drop in noise was only a 29% drop.

If you think about the typical PC air flow it is much like this machine - other than the cold air CPU duct. All he really did was to use ducts and internal fans to better focus that air flow. In effect the cooling air is used in a sequence (HDD ==> GPU ==> chip set ==> PSU & CPU ==> PSU). It also seems to me that the PSU is an air flow bottle neck that results in increased air flow impedence. Thus he needs more fans to have enough air flow. Would it not be better to use ducts to divide the cold intake air into seperate streams for each device that needs cooling and then vent that warm air from each device out of the case?

teknerd, you may need to check your math.
A 29%dB reduction from 55dB is 16dB

He He He ... [sits quietly on sideline and watches... further discussion...] ...

Sleeper:
Sound measurement in dB is not linear. An increase of 10dB doubles the sound while a decrese of 10dB cuts the sound in half,

Yes well, not really. Each 3dB sound pressure doubles/halves.. I wont bother countinng how many percent that is.. *lazy* Oh, Happy new year! 0:05 here.

the 3dB figure is when you add a second identical noise source (ie: two identical fans), then sound pressure incrases by 3dB

nici, Happy New year !!!


(Oh.... and the_scarf )

Okay.. Im stuck in hi-fi here.. You know, to increase SPL 3dB you need double the power.(hurray! i know something ) Oh well, you learn something new every day

I believe that still holds true in this area. However i think there is a difference between the power and the volume.

There seems to be some confusion here. Twice the electrical power is +3 dB, half power is -3 dB. However, the human brain/ear subsystem responds logarithmically, so to takes a 10 dB increase to SOUND twice as loud, a 10 dB decrease SOUNDS half as loud. That is why two identical fans don't SOUND twice as loud as one.

ok im a bit confused here.. so it is 3dB, but the human ear doesnt understand that and it thinks its 10dB? Yeees, maybe ill just shut up and go home.

No, it is not that the human ear perceives an increase of 3dB as an increase of 10dB. What Bill means is that the human ear doesn't perceive an increase of 3dB as twice as loud even though it is (in power), it's not until the sound has increased 10dB that the human ear perceives it as twice as loud.

Holy CR_P!
Man I did not mean to start something here.

I only meant to point out that the author does not compare dB to noise.
Since dB is used exclusively here, it is linear.

Peace man!

Now the author have fixed sound reduction to 97%.

*sigh* http://www.blanket-insulation.com/AcousticHTML/FAQsound.html

So a 16 dBA reduction corresponds to more than %82 absolute reduction