It will sound like an AC30 on steroids and will of course be objectively better in every way 🙂
I think that the EL84's draw all their plate current through the choke anyway but I could be wrong, as I'm a complete newbie to this but it looks like it on the schematic I'm roughly working off (http://www.blueguitar.org/new/schem/vox/ac30_pwr.gif).
My general plan is to use aforementioned copper caps and therefore keep some advantages of tube rectification without the need for a 5V winding. That active voltage regulator looks good but not sure if it'll handle 350V input. Will look into it though. My main concerns seem to be the current through the choke and the transformer B+ tap which is meant to be taken before the choke but results in 200V ripple.
I think that the EL84's draw all their plate current through the choke anyway but I could be wrong, as I'm a complete newbie to this but it looks like it on the schematic I'm roughly working off (http://www.blueguitar.org/new/schem/vox/ac30_pwr.gif).
My general plan is to use aforementioned copper caps and therefore keep some advantages of tube rectification without the need for a 5V winding. That active voltage regulator looks good but not sure if it'll handle 350V input. Will look into it though. My main concerns seem to be the current through the choke and the transformer B+ tap which is meant to be taken before the choke but results in 200V ripple.
I guess I don't understand how tiny caps will lower the B+, other than their limited ability to hold up the voltage under load. But that results in hum rather than smooth but lower DC.
Here is a collection of Vox schematics, including a bunch of AC30 variations, perhaps it will be useful. Vox Amp Heaven Schematics - Berkley Cambridge Pacemaker Foundation Defiant Conqueror Escort Super Midas Busker Vigilante
Here is a collection of Vox schematics, including a bunch of AC30 variations, perhaps it will be useful. Vox Amp Heaven Schematics - Berkley Cambridge Pacemaker Foundation Defiant Conqueror Escort Super Midas Busker Vigilante
OK I'm wondering one other thing now; will a 15H choke rated for 360mA survive in this circuit when the peak current just after turn-on is 573mA? I.e. I found a 15H choke for cheap on ebay. The maximum current after this should only be 200-250mA but there is a peak just after turn-on and I was wondering if this would result in smoke and flames or is it nothing to worry about? Here is my power supply in this setup.
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