[Don Pearce]

On Sun, 14 Jan 2007 20:07:06 GMT, (Don Pearce)
wrote:

On Sun, 14 Jan 2007 13:23:13 -0600, John Byrns
wrote:

Can you explain in more detail the "Gaincard method" of counting
components in the signal path? Ignoring the fact that you don't seem to
be including the output transformer in your count, I still can't
duplicate your count for the "KISS Amp WE300B SE Ultrafi"

A much more interesting number is those components that can do
something to the signal. Those are either the ones in the direct
signal path or those that have a signal voltage across them. Some
components in the signal path have essentially zero signal voltage
across them and are thereby incapable of altering the signal.

Now, counting properly, components in the direct signal path are

Input pot
4 by 220R grid stopper
First valve
Coupling cap
220R grid stopper
Second valve
transformer
47k feedback r
200uf B1 decoupler

That's 12

The signal handling components with first order effects are

Battery
10 anode load
200uF B2 decoupler
47k grid leak
56uf cathode decoupler
1k cathode load

That makes 18 total.

Buggered if I can see the relevance of the number though. Any signal
that hits this amp has already been through a few hundred other
components. Of course the whole thing makes a bit of sense when you
consider that the components in this amp are doing a
disproportionately huge amount of damage to the signal. Which they
are. Ultrafi is an interestingly ironic name, don't you think?

d

Sorry, miscounted. I hadn't spotted the two 100 ohm resistors and 100
ohm pot forming the series feedback network on the output valve were
carrying signal. Hang - this amp is not meant to have any feedback -
what are they doing there?

d

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