In Reply to: A tale of two amps posted by PaulF70 on February 14, 2021 at 12:31:15:
I came across something I found very interesting on another forum recently. Here it is:"Some time ago, I had my Cary CAD-211AE amplifier (110W push-pull) on my engineer's bench to do some repairs. We had a very interesting conversation. It went something like this:
Him: "Look at this. The voltage rail on the push part of the circuit measures at 904V. The voltage rail on the pull part of the circuit measures 890V"
Me: "You are saying that the push voltage and the pull voltage are different? Will that affect the sound?"
Him: "Yes it will"
Me: "Why are the push and pull voltages different?"
Him: "Because of valves. Most likely the valves on the push side are of a different specification to the pull side""
He goes on to note that this is unavoidable. Even valves that start life equivalent will drift.
Things I'm wondering:
- How could ANY push-pull (or "differential") amp avoid such a problem?
- This has to have some audible effect on the signal - especially low-level signals. (Hmm, that's just where SE amps really shine, isn't it?)
Thoughts?
Edits: 05/08/21
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Follow Ups
- RE: A tale of two amps - PaulF70 08:12:23 05/08/21 (4)
- RE: A tale of two amps - tube wrangler 12:59:24 05/22/21 (1)
- RE: A tale of two amps - PaulF70 18:37:25 05/28/21 (0)
- RE: A tale of two amps - PaulF70 18:24:39 05/12/21 (1)
- RE: A tale of two amps - PaulF70 17:39:05 06/03/21 (0)