CPU heatsinks in my Zen Amp

[Gubby]

Dear All,

this is my first post on this forum.
Let me quickly introduce myself: I'm belgian (from Brussels, the capital of Europe, of waffels, of beers & of sprouts). I'm 33 years old, married, 1 little child and I work in IT for a bank (but I'm a physicist). I'm an "audiophile" but I'm not rich --> I'm a DIYer.

OK I stop now... I don't need a date

My first realizations: a wonderful "Bride Of Zen" preamp with external power unit (wonderfull compared to the preamp part of my NAD C312), a marvelous external power unit for my MSB Link DAC (based on the MSB P1000 model).

Now I'm building a ZEN amp (v1) to marry with my preamp. And of course, you understood: I made an external power unit
For the heatsinks I choosed to use 4 CPU coolers (Zalman 5100 AlCu), one by transistor (2xIRFP9140,2xIRFP240). Of course I removed the 4 stock fans (too noisy) and I replaced it with 2 "silent" 8 cm PAPST fans ("12 dB" rated, let say 20 to 24 dB in the real life).

I made some calculations, each transistor should dissipate about 35 to 40 Watt, this is much less than a AMD CPU at 2 GHz (80 Watt )... My silent fans don't cool as much as the stock ones, but it should be enough (I need about 1°C/W by heatsink and they are rated 0.4 °C/W with the noisy fan).

I didn't finish yet my amp so I didn't test it...

So my questions are:

Does somedy already try this cooling solution ?
What do you think about this ?
Dont'you think it's a good idea ? Are you interested by some pics ?
Why "Classe A" should always be synonym of "fu..ing heavy black heatsinks" ?
Why don't use the computer technologies progress for the HiFi ?

[tschrama]

Hi,

Millwood has posted a picture of his JLH 10W Class A with a pentium II heatsink... Since then I tried it too, I use a single AMD700MHz heatsink with 2 fans which are turning at a very low speed.. this cools my 2 channel MOSFET JLH 10W Class A just fine... goodluck,
Thijs

[Gubby]

Hello Thijs,

thanks for the info.
I made some search on this forum and I saw that I was not the first to have this idea

Anyway it's a good news (even if I thought I was a genious ), it seems to work fine especially with Zalman heatsink and Papst fans !

Even Mr Pass tried and seems to think it's a good idea... the Force is with me

So I'll try to finish my project quickly and I'll keep you informed...

[Gubby]

This is a picture of this cheap Zalman heatsink CNPS 5100-AlCu.
Of course you need 4 such heatsinks for a Zen v1 amplifier 2x10W...

[Gubby]

PAPST 8412 NGLE - 12 dBA
I use 2 of them (1 for 2 Zalman heatsinks).

Just "listen" to it...

[azira]

Originally posted by Gubby
...
Of course you need 4 such heatsinks for a Zen v1 amplifier 2x10W...

I used only 2... These are some surplus Foxconn heatsinks designd for Athlon 1800's and below. The 4 holes used to mount a heat spreader, took it off and I have all the mountings equip I need for removing up to 100W of heat. 24V source, wired fans in series. Not quiet.. but neither is my table saw which is usually also on at the same time gotta love garage hobbies...
--
Danny

[Holger Barske]

I have tried these:



Didn't go for it, was just too noisy, even with reduced voltage on the fans.

[tschrama]

If it is too noisy, try even lower voltage till you get something like 100-200 rpm.. (? 4Volt?) but a real problem with 2 or more of this fans it their beating when their rpm is just slightly different..

[Gubby]

Hello Everybody,

I just finish my Zen amp (v1) with the 4 CPU heatsinks (pictures are coming soon...) yesterday. I married it with my BOZ and I made a first test and....UNBELIEVABLE !!!
Even with a Sony Discman CD player as source , the sound is 10x more detailed than everything I ever heard ! (before I used the power amp part of a NAD C312 integrated amp).

Today I'll make a first test in my living room with my NAD CD player + MSB Link DAC. I'll sit down on the floor , this is safer...


Stay tuned...

[Nelson Pass]

I have a nice SOZ type using the Zalman "mushroom"
sinks mounted on an X1 chassis, but it's not done yet.
Picture will follow if you guys don't post it first.