Hoffman Amplifiers Tube Amplifier Forum

Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: kagliostro on August 13, 2023, 07:08:36 pm

Title: Seeking for schematics that uses Anti Humm Lift (like VOX AC30CC2)
Post by: kagliostro on August 13, 2023, 07:08:36 pm

Some amp (like the VOX AC30CC2) use a circuit like this to avoid Humm
(also Merlin on his books has a version of this circuit)

(https://i.imgur.com/0LvFw8O.png)

Here the Power Section of the AC30CC2

(https://i.imgur.com/z37I27c.jpg)

I'm seeking for other amp schematics that uses the same circuit

Plese, if you have a link share it

THANKS

Franco

Title: Re: Seeking for schematics that uses Anti Humm Lift (like VOX AC30CC2)
Post by: sluckey on August 13, 2023, 08:00:35 pm

https://el34world.com/charts/Schematics/files/Fender/Fender_63_reverb_manual.pdf

Title: Re: Seeking for schematics that uses Anti Humm Lift (like VOX AC30CC2)
Post by: tubeswell on August 13, 2023, 09:52:36 pm

PV did it on a few of their amps (Classic 30 etc). Fender did it on the 63 Reverb RI

Title: Re: Seeking for schematics that uses Anti Humm Lift (like VOX AC30CC2)
Post by: kagliostro on August 14, 2023, 10:07:43 am

Many THANKS Steve & Tubeswell

Franco

Title: Re: Seeking for schematics that uses Anti Humm Lift (like VOX AC30CC2)
Post by: Williamblake on August 14, 2023, 10:30:56 am

In first post first example: could current flow from 35V to ground or from -35V to ground? I do not see a DC connection.

Title: Re: Seeking for schematics that uses Anti Humm Lift (like VOX AC30CC2)
Post by: sluckey on August 14, 2023, 11:05:06 am

Quote from: Williamblake on August 14, 2023, 10:30:56 am

In first post first example: could current flow from 35V to ground or from -35V to ground? I do not see a DC connection.

No. What do you mean by "DC connection"?