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AudioGeek
05-May-07, 02:51
I have a passive transformer volume control. What is the input impedance of the AMP4 and will it work ok with a passive volume control??

txs!

xenob
05-May-07, 10:41
Hi,

Do you use those fancy Stevens & Billington transformers?

When building AMP4 you can set any input impedance you want (usually 20k or 49k).

I made the experience that a low value passive pot (eg. 10k log) fits best to a high (49K) input of the amp.

Please consider: the source has to be able to drive the load of the pot and
too high resistor values at the amp input can introduce noise.

AudioGeek
06-May-07, 01:49
pretty much... something similar.

probably go with 49K input resistance.

cd player has 100-200 ohm output impedance.