Freon cooling an amp?

[star882]

Since amplifiers emit heat and heat causes Johnson-Nyquist noise, why not flow Freon through metal plates attached to the semiconductors? In theory, low temperatures will reduce noise.
http://www.xtremesystems.org/forums/...ad.php?t=95962
They have successfully done this with computers. Why not audio amps?

[jgwinner]

Although the reason they did it with PC's was to increase the clock rate, not so much noise - but it sounds like an interesting idea.

I have been seriously thinking about water cooling a HTPC amp, mostly because finding 7 big heat sinks and cramming them all in a case isn't trivial. This would reduce the heat some but not as much as a freon powered one! (I hope you'd use something safer but I get the idea).

No doubt some people of the more subjective variety will say that your amp would sound "Crystaline" no doubt

[ak_47_boy]

I am building a 60 chip DAC based on the tda1543. I was thinking about liquid cooling. I have heard they start to distort if they get really hot. I don't know if this means they would become better at very low temperatures. I guess you could increase the voltage also. It could be something to look into.

I see insulation to be a problem since any material on the board is going to add a small amount of cross talk. This would be the time to use that 3M liquid stuff that does not conduct electricity.

[jaycee]

Pretty much any cooling substance is going to form ice, which means water, which means *bzzzt* *poof*. I've seen small scale experiments done with liquid nitrogen on CPU's, but these are usually just to see if it's possible - the board is usually dead in a few hours due to the cold affecting parts like capacitors and other semiconductors, and due to the condensation.

Such cooling systems i've seen for PC's usually use the same system that is used in a refridgerator, with a heating jacket around all pipework so that condensation doesn't form. They're power hungry and noisy, and usually only for the nutters who want to get an extra 70MHz from their cpu by spending more money than they would by buying a new cpu!

[MJL21193]

Originally posted by jaycee
Pretty much any cooling substance is going to form ice, which means water, which means *bzzzt* *poof*. I've seen small scale experiments done with liquid nitrogen on CPU's, but these are usually just to see if it's possible - the board is usually dead in a few hours due to the cold affecting parts like capacitors and other semiconductors, and due to the condensation.

Such cooling systems i've seen for PC's usually use the same system that is used in a refridgerator, with a heating jacket around all pipework so that condensation doesn't form. They're power hungry and noisy, and usually only for the nutters who want to get an extra 70MHz from their cpu by spending more money than they would by buying a new cpu!

Very well said. There's just not enough to brag about with simple heatsinks...

[Johan Potgieter]

Not quite my field, but I am of the notion that there is a lowest operating temperature for semiconductors. One must not loose sight that there is still a small temp. step between the semiconductor surface and the metal base. One finds that air-flow can make quite a difference, so I am not convinced that the final sentence of Jaycee per previous post is not a factor.

[Cloth Ears]

Originally posted by star882
Since amplifiers emit heat and heat causes Johnson-Nyquist noise, why not flow Freon through metal plates attached to the semiconductors? In theory, low temperatures will reduce noise.
http://www.xtremesystems.org/forums/...ad.php?t=95962
They have successfully done this with computers. Why not audio amps?

Aside from the reasons mentioned above, and that freon is bad for us ("What do you mean, 'bad'?" - "Try to imagine all life as you know it stopping instantaneously and every molecule in your body exploding at the speed of light." ), I'm not sure what you're hoping to achieve. With noise levels of -130dBM at 50 degrees Celsius at 20kHz, I don't think there is any way you can flow any coolant in your amplifier that wouldn't generate more noise than you are trying to reduce.

Better would be trying to work out a better way to get the air to flow around your heatsinks so that you get better cooling that way. How many times have you seen a lovely array of vertical heatsinks that are situated so that they are only millimetres above the surface that they are sitting on (ie. no flow).

[Original Burnedfingers]

About 15 or 16 years ago I repaired an amplifier that used freon in its heatsink. I cannot remember the name of the amplifier right now. It worked as far as cooling went the drawback was you had to have it in its normal operating position in order for it to cool correctly. This made it hard to work on the amplifier and to obtain test voltages when it was in operation.
I think maybe cost and the fact that if exposed to fire the gas is not people friendly.

[Original Burnedfingers]

It was an Optonica amplifier

[Johan Potgieter]

Originally posted by Cloth Ears

How many times have you seen a lovely array of vertical heatsinks that are situated so that they are only millimetres above the surface that they are sitting on (ie. no flow).

AMEN TO THAT!