In Reply to: Very good point. posted by sser2 on March 3, 2017 at 14:00:55:
"In a typical AB2 tube stage, drivers output impedance should not exceed 500-600 Ohm. This can only be achieved by a combination of low Rp PP driver stage AND a step-down interstage transformer."
It can also be accomplished using cathode followers reactively coupled to the output stage with chokes (or a center-tapped choke). Altec did this in the 1570B, and I used it for my A2 211s.
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Follow Ups
- RE: Very good point. - Triode_Kingdom 18:28:36 03/04/17 (2)
- Interesting circuit. - sser2 23:40:34 03/04/17 (1)
- RE: Interesting circuit. - Triode_Kingdom 08:41:16 03/05/17 (0)