• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Phase splitters. Phase shift and frequency response.

Does anyone use a pentode-triode combo for phase splitting SE inputs?

At a minimum, there are 2 "flavors" for tri-pent small signal circuitry in power sections.

Quite common is pentode voltage amplifier DC coupled to "concertina" phase splitter. This configuration is found in Dynaco, Sherwood, and later Scott products.

Older Scott units used the tri-pent in an asymmetrical paraphase configuration.
 

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Not sure I understand the question.
But Radford (who Bailey was associated with) made their MA15/MA25 and STA15/STA25 amplifiers with exactly that topology.
There were kit versions for a short while from HIFi mags, but I do not know if anyone uses it for DIY builds.
 

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HickKUK,

Does anyone use a pentode-triode combo for phase splitting SE inputs?

I did in several amps I built. The Bayley type splitter you are pointing to is a clever variant of the Schmitt ("short tail") inverter and has a few pros.

If you can read German, here is a link to an additional analysis of a real world implementation (Radford circuit, found in a French magazine) I wrote quite some years ago:

Denk mal wieder!

Kind regards,

Tom
 
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