[tangent]

slindeman's got it exactly right.

The Hansen board was originally the CMoy amp plus Meier EB crossfeed, plus a second pair of op-amps acting as buffers.

Apheared then figured out how to take the Hansen board and build his Apheared 47 amplifier on it by taking over the crossfeed section of the board and using it for other purposes. The A47 on a Hansen board is a CHA47.

And yes, you can build a plain CMoy amp on a Hansen board, but it's kind of wasteful.

 

[millerdog]

Okay! The CHA47 can be built on the hanson board.
The CHA47 is a proprietary design based upon this board.
If you want a cmoy with crossfeed it can be built on this board. If you want a CHA47 with crossfeed it cannot be built on this board.
have I got it right?
md

 

[tangent]

Close enough, millerdog.

You could lash an outboard crossfeed circuit to the CHA47, but the point is that you can't use the crossfeed circuitry on the Hansen board if you do the CHA47 modification, because the holes and traces are used for something else.