AA864 musing 6L6 to 6V6

[ok_state_blues]

Hello all. I am really interested in the pseudo express amp a la AA864 that is listed on here:

https://el34world.com/Forum/index.php?topic=26289.0

My question is how can this amp be reworked to run on 6v6 tubes rather than 6L6? I have plenty of 6v6 tubes/transformers but not so much iron for 6L6. Can this be done or should I just save up for the right iron?

[Willabe]

Welcome. 

Just build a single channel Deluxe Reverb, ~22w or Princeton Reverb, ~15w, without the reverb and tremolo.

https://el34world.com/charts/Schematics/files/Fender/Fender_deluxe_reverb_ab763.pdf

https://el34world.com/charts/Schematics/files/Fender/Fender_princeton_reverb_aa1164.pdf

[sluckey]

My question is how can this amp be reworked to run on 6v6 tubes rather than 6L6? I have plenty of 6v6 tubes/transformers but not so much iron for 6L6. Can this be done or should I just save up for the right iron?

You will need a PT that puts out lower voltage as well as an appropriate OT for 6V6s. Probably need a small tweak to the bias circuit.

[dwinstonwood]

Like sluckey said.

The Hammond 290 D2X has both 710VAC and 610VAC secondaries. Use the 610 secondaries for 6V6's, and if you ever want go with higher B+ you won't need to buy another PT.

https://www.hammfg.com/files/parts/pdf/290D2X.pdf

I suggest the 1760H 20W OPT: https://www.hammfg.com/files/parts/pdf/1760H.pdf

That way, you have multiple speaker Ohm taps if you build a head.

[PRR]

...I have plenty of 6v6 tubes/transformers but not so much iron for 6L6....

Maybe just use the "6V6 iron" you have? The pin numbers will be the same. The bias won't be a lot different.

[ok_state_blues]

Awesome advice from everyone. This will be a slow build but I am thankful for the advice and will most likely follow up as I make progress

[ok_state_blues]

My question is how can this amp be reworked to run on 6v6 tubes rather than 6L6? I have plenty of 6v6 tubes/transformers but not so much iron for 6L6. Can this be done or should I just save up for the right iron?

You will need a PT that puts out lower voltage as well as an appropriate OT for 6V6s. Probably need a small tweak to the bias circuit.

Whenever you say slight tweak, can you expound? Do you mean bias wise adjustment at the pot or a value change to a component?

[sluckey]

6V6 requires a lower range of negative bias voltage than a 6L6. With a 10K pot there will probably not be enough range to cover 6L6s and 6V6s. To get to a lower range of voltage you can increase the size of the 470Ω (often called bias range resistor) or you can decrease the size of the 27K connected to the pot. Very easy to do experimentally. 6V6s will typically want about -35V for proper bias.

[ok_state_blues]

Awesome information thank you for the quick reply.