AC15 clone using Hoffman AC30 layout

[Big_Mike]

Hi guys,

I am thinking of building a Vox AC15 clone using the Hoffman AC30 board and layout.  Having the normal and top boost channel will be great.

There are three small changes that I want to make.  Obviously, I only need two EL84 outputs, so I assume I can just trim the layout down to two output tubes rather than 4?  Any other component parts I need to change?

Second, I would like to make it solid state rectified instead of tube rectified.  How would the layout look for that?

Finally, I am going to add a Lar-Mar master volume, but that will be fairly easy to do.

Any help on the first two points would be greatly appreciated!

[Big_Mike]

Ordered the chassis, transformers, and components for this build.  I am using the Hoffman AC30 board and layout, just reducing the output to two tubes.

Really excited for this project.  I figure I can build an AC15 clone that sounds much better and more like a JMI than the current Vox handwired series offers.

[Big_Mike]

I purchased the transformers for this build, and I am using a Hammond 290px.   I have a couple of questions on the hookups with the Vox AC30 layout.

First, on the hookup for pins 1 and 2, I assume hot goes to pin 2 and neutral goes to pin 1?

Second, I am a little confused on the secondary 6.66 volt heater wiring.  Pins 5 and 6.  5 is zero volts, 6 is 6.66 volts, and there is a black wire for 3.33 volts.  How should I hook those up for the heaters?

Below is a link to the wiring diagram for the 290px:

https://www.hammfg.com/files/parts/pdf/290PX.pdf?v=1697661948

[SEL49]

First, on the hookup for pins 1 and 2, I assume hot goes to pin 2 and neutral goes to pin 1?

That's correct. But you should also connect pin 3 to pin 1 and pin 4 to pin 2.

Second, I am a little confused on the secondary 6.66 volt heater wiring.  Pins 5 and 6.  5 is zero volts, 6 is 6.66 volts, and there is a black wire for 3.33 volts.  How should I hook those up for the heaters?

It's just a 6V winding with a center tap (black). Pins 5 and 6 are the filament string that you connect to the tube filaments. Connect the black wire to ground to reduce filament hum.

[Big_Mike]

First, on the hookup for pins 1 and 2, I assume hot goes to pin 2 and neutral goes to pin 1?

That's correct. But you should also connect pin 3 to pin 1 and pin 4 to pin 2.

Second, I am a little confused on the secondary 6.66 volt heater wiring.  Pins 5 and 6.  5 is zero volts, 6 is 6.66 volts, and there is a black wire for 3.33 volts.  How should I hook those up for the heaters?

It's just a 6V winding with a center tap (black). Pins 5 and 6 are the filament string that you connect to the tube filaments. Connect the black wire to ground to reduce filament hum.

Thanks for the info, I wonder why you have to wire up the 120v to both pins 1-2 and 3-4?  Is that just to feed separate secondaries?