[Possum]

The schematic I used is almost exactly the same as Kevin's original. The only differences are the transformer I used, the number and size of capacitors, the first regulator stage (LT1085/LT1033 to replace LM317/LM337, implementation and resistor value calculations are in the datasheets), and resistor values of the tracking op amps to get ~15.9V rather than 16.4V. The resistors you use with the first regulators will depend on what transformer you have.

 

[Jupiter]

Quote:

Originally posted by kevin gilmore The 505PHC850K is the best and fastest of the bunch.

Anyone know where to get this cap in small quantities? I've already tried Illinois Capacitors. (They require a minimum quantity of 50 for this cap.)

 

[eric343]

My god, Kevin, that's more insane than Jan Meier's 47 opamp power amp! I hope you didn't have to drill all those holes yourself...

Apheared's amps haven't got *anything* on that... just *when* did you escape from the asylum?

And water-cooled too... Have you ever considered doing a Cray-2 style power amp?

Those Wilsons deserve something that looks cool

 

[aeberbach]

I really value Kevin. Apart from designing great stuff for us and sharing, he makes anything I do look absolutely rational. Next time I have doubts about whether I really need some bit of gear I'm going to look at the image of those 84 transistors on the water cooled heatsink, and remember that it's only one channel and that he's not even powering a 400-seat cinema system

 

[eric343]

Whoawhoawhoawhoa.... that's only ONE channel?! And just this afternoon I was wondering why Kevin didn't seem to go in for monoblocks - that Krell he's got in the photo in his page isn't a monoblock... (I think that Krell is the only component of his system that I've ever heard; hooked up to some Martin Logans and an SCD-1)

 

[kevin gilmore]

No that is an entire stereo channel.

Each amp is 14 transistors times 4 for a full H bridge.

Each amp is driven with 13 power transistors for the positive
rail and another 13 power transistors for the negative rail.

That is 164 transistors total, plus a couple more for the
bias drivers.

You don't even want to know what the motorola transistor
bill was.

If i set the chiller at 18 degrees C, even at full blast the
amp pulls heat OUT of the room...

Right now i have the bias set at a fixed 200 watts per channel.

It really sounds sweet.

Schematics and the code that goes in the micro that controls
the bias by the end of this year.

 

[eric343]

Oh, okay, I thought you were crazier than I thought. That makes more sense now; I was wondering how two of those big "transistor boards" would affect the sound when you prop 'em up in the room...

And I'll bet it sounds sweet... if only I had the time, money, space, skill...