In Reply to: BTW- Power Amp with Passive Pre posted by Neff on July 11, 2012 at 16:44:22:
A passive volume setup may not work, due to low power amp I/P impedance. You really have to be prepared for the 10 KOhm IHF "standard". However, a "unity" gain buffered volume control will do quite nicely. Buffering makes a 100 KOhm volume pot. feasible in combination with a low I/P impedance power amp.
A cheapy 25.2 VCT "Rat Shack" power trafo, 4X 1 A./50 PIV Schottky diodes, 2X 'lytics of decent size, a 7812, and a 7912 make a bipolar PSU suitable for JFET source followers in the buffer role. The only cap. in the signal path is an O/P coupler.
Eli D.
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Follow Ups
- RE: BTW- Power Amp with Passive Pre - Eli Duttman 17:56:16 07/11/12 (8)
- RE: BTW- Power Amp with Passive Pre - Bold Eagle 05:04:00 07/14/12 (7)
- RE: BTW- Vintage Power Amp with Passive Pre - Neff 06:14:54 07/14/12 (6)
- RE: BTW- Vintage Power Amp with Passive Pre - Bold Eagle 10:13:21 07/14/12 (5)
- RE: BTW- Vintage Power Amp with Passive Pre - Eli Duttman 13:11:20 07/14/12 (4)
- RE: BTW- Vintage Power Amp with Passive Pre - Bold Eagle 17:11:18 07/14/12 (2)
- RE: BTW- Vintage Power Amp with Passive Pre - Eli Duttman 18:04:49 07/14/12 (1)
- RE: BTW- Vintage Power Amp with Passive Pre - Bold Eagle 18:30:48 07/14/12 (0)
- Handcuffs........ - Neff 13:59:26 07/14/12 (0)