Krell KSA 100 type amplifier


Paid Member
2001-02-25 7:10 pm
Northern Iliinois
There was a guy named William C. Snyder who published a spiral book called "Class A Audio Design". Mr Snyder was an engineer at Krell for a while.

It wasn't a bad book. In my mind, nothing earth-shaking and I don't recall seeing any stated Krell product schematics. However, it's probably reasonable to assume there be a lot of similarities though.

It's written much in the style of a college course notes book. Circuits were complementary symmetry type, some talk about JFETs and MOSFETs as gain elements. Used discrete JFET input gain block as DC servo.

The copy I had was from 1990. The address at that time was:
New England Analog
Rt. 113A
P.O. Box 38
North Sandwich, NH 03259
I wrote once to ask him a question and ask if PCBs were available for any of the circuits described. He said they would be, but I never heard anything else about it.

Hey, I'd be interested in seeing a schematic for the KSA100 myself. Not that I'd want to build it, but I'm a curious guy!:)

Speaking of Krell, is it true that their amps uses very complicated circuit design? I say complicated because there are tons of components if you look inside the chassis. Also, does Krell allow diy like us to copy and use their circuit to built our own amps? Their old chassis design looks so beautiful and now their current product looks so .....
Krell Clone

Hi There

I have actually made a Krell KSA100 MKII clone a few years ago.
It was build as monoblocks with 1200VA 40-0-40 transformers for each block. The schematics is not that complicated, but some af the original parts (Supertex fets) are out of stock and are not made annymore. The driver/output stage uses 2SC968/2SA2238, MJE15030/MJE15031, MJ15024/MJ15025. 8 otuput devices pr channel. I am working on a KMA 100 clone. I is should to be a lot better. It has a regulated pover supply for the input stage. Annyway the KSA 100 MKII curciut i originaly made was a VERRY good amp.