• 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.

6V6 line preamp

Thank you! Nothing personal, but that is how threads get so long that no one wants to read them. I already feel bad for the clutter I have caused. Feel free to delete non important discussion, mine included, as this is a specific build thread that is relatively short at the moment.
 
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Kevin,
Care to expand your comment reguarding recent experience. Was your recent experience pro or con regulator?

My experience with regulators has been nothing but positive till I do something stupid with them.

I recently ran into a situation with my transformer coupled 26 line stage where the "improvements" in a particular regulator design which measured spectacularly well also made quite a footprint on the sonics - which in this case resulted in a spectacular compromise in sound quality. It may be the case that once the source impedance is down to a few tens of ohms you start to hear the regulator and not the capacitor across its output terminals. (A good compromise seems to be when the regulator dominates the source impedance up to a few hundred Hz and then the cap(s) take over.) I don't think this is an issue with RC coupled circuitry at all, but it is quite interesting with transformer coupled designs. The supply in question is a series pass with 6V6 series pass in pentode connection with a cascode 6DJ8 error amp with a zener reference.. I've had some luck with CCS based designs and am going to revisit the shunt thing soon.
 
It could, but the dissipation should be much higher than 6V6 class which is already nicely linear in triode. Fat older ST bottle (Coca Cola style) 6V6 tend to sound mellower and be more ringy in this application. In power amps the output transformer ratio extinguishes the voltage gain into current transformation so microphonic behavior its not noticeable.

Did you try this one?

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