FirstWatt J2

[AR2]

He, he,
yes that's how water cooling is working, we know that but...
How loud is the pump? How big that system needs to be - PC level or car level for typical class A amp we are using? These are the specific that will determine how usable that is. If I have to have a loud pump that is equal to me as a forced air. In that case neither one will fit. But if someone was able to use quiet PC system that is easily available with obviously low prices - several manufactures are offering it, than that might be a way to go. I have no idea what PC cooling systems are designed to handle, but I doubt they will be able to cool even 2 pairs per side of typical Mosfets biased to 0.6V on the source resistor.

[zhoufang]

When the packaging allows for 350degC operation, we can just let the JFET boil water and release the steam to outdoor.
Then the amp will be consuming deionized water other than electricity.
A 1000W consumption amp will convert 1.59kg of water into steam every hour.
Seems like a lot.
So maybe recycle the water will be better.
Anyway it will be pretty easy to convert steam to water, compared to cooling warm water.
Plus, no pump needed.

But wait... Isn't this gas cycle exactly same as the way heat pipes work?
So we came back to the origin, just use a finned cooler with heat-pipe build in will do the job well.

[labjr]

You need like a gravity heating system to cool the amp which uses refrigerant instead of water. However, you still have to remove the heat.

[Tea-Bag]

Wow. This discussion has veered into nonsense.

[AR2]

Oh, I love this, our amps will not just play the music, but they will whistle as well.

[rolandong]

Just an idea, why not a class A amp connected to shower heater.
Besides, these sicJFET is intended for solar power of some sort

[flg]

Well it's not nonesense. But, it may be difficult to take advantage of these principles better than what has already been done. For instance the nucleate boiling principle works fine. Using water however dictates your temp regulation at 100C (212F). I would be happier with my packages a little cooler than that. You just use a fluid with lower bopiling point Still, kinda messy though.
Heatpipe, cpu coolers are interesting. Most all use forced air cooling though. To reduce the air noise you would need to slow down the fan and derate. Most of these units are made for processors from 80-150W. It's easy to use a TO247 film resistor with known characteristics and a power supply to test these things...
I think a self powered, auto circulating, sealed, water cooling idea has the most promiss. The PC guys already do that too.

[Telstar]

Originally Posted by zhoufang

And talking about small case, a good SMPS will be useful too.
A near silent (<30dB) active cooled heatsink (heatpipe + fins), with SMPS, we could get a self-contained high power class-A amp in a real small package. This will be cool.

Yes, i wanted to point ou that the fanless thermal resistance of the HR-01 is quite poor, probably unable to dissipate 50W, and raises dramatically with a very little fan.

I should have known that that's where you were going. And i'm sorry but that's not my cup of tea.
I have tried an undervolted Nexus fan, such as the ones in SPCRW reference tests, which should be 18-19dB and i HEAR IT at 1.9m of distance wit closed case.

So any fan in hifi equipment is a total turnoff for me.

Watercooling unfortunately also need a fan. You can look into TEC cooling, with external units that may do without fans.

[Magura]

Originally Posted by AR2

He, he,
yes that's how water cooling is working, we know that but...
How loud is the pump? How big that system needs to be - PC level or car level for typical class A amp we are using? These are the specific that will determine how usable that is. If I have to have a loud pump that is equal to me as a forced air. In that case neither one will fit. But if someone was able to use quiet PC system that is easily available with obviously low prices - several manufactures are offering it, than that might be a way to go. I have no idea what PC cooling systems are designed to handle, but I doubt they will be able to cool even 2 pairs per side of typical Mosfets biased to 0.6V on the source resistor.

Take a look at FLG's answer, that's what I'm talking about. No pump needed.

As for the 100C figure, why would that be a problem regarding the Semisouth devices?
As I understand it, the only reason to keep them as low as 100C is the plastic of the package. The die should be good for like 700C as I recall.

...and no TeaBag, this is not nonsense, but quite advanced development, as we for once actually can use the nuclear boiling principal, using plain water, for cooling a device, as the device can deal with the higher temp.
Think about it, and you will find that all of a sudden, quite small boxes becomes an option.

Magura

[Telstar]

Originally Posted by Magura

Take a look at FLG's answer, that's what I'm talking about. No pump needed.

No pump needed means no fan. I like it