I think the ADA Ampulator, a respected "power tube saturation pedal", uses this approach.
ampfixer at aol.com wrote:
>Joe, I have also experimented with micro-power amps using a 12AT7 for the
>output section, and have found that the typical reverb drive transformer is a bit
>too wimpy to provide adequate bass response. It's fine for reverb, of
>course, since you *want* a high-pass filtering effect in that case.
>
>I happen to like the "push-pull" sound (whatever that is <g>) and I
>breadboarded an unusual method for obtaining this at ultra-low volume. I
>used an old surplus 10k:8 P-P output transformer and used the two halves of a
>12AT7 "preamp" tube as a push-pull pair, driven by a cathodyne phase inverter preceded
>by a single voltage amp stage and a volume and tone control. It sounds
>pretty decent and power output is about 1 to 2 W.
Would you drive an inductive load, or a guitar speaker with this output? I'll bet a guitar speaker would sound much better than an inductive load. There needs to be a way to equalize after the power amp. If you use an inductive load, you can run the final output right into an EQ. If you use a guitar speaker, you would mic that and send the mic signal into an EQ.
Suppose you had a great tube power amp putting out 2 watts. Suppose you hook it up to a 25 watt Greenback guitar speaker. Would it sound worse than a 15 watt tube amp driving the speaker? I suppose that a guitar speaker doesn't sound really good until it's being pushed hard.
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