Fender Bassman Head 6G6-B circuit conversion

[Jazz P Bass]

Each pair of tubes is wired with the plate (Pin #3) in parallel.
Should be easy to see the wire.

[tonefiend]

I confirmed that both pairs of Output tubes are wired in parallel, Is there any reason that I couldnt rewire the original set of output tube sockets back to original, and disconnect the 2nd set of tube sockets?

This keep in mind is with an OT from a Fender Twin. OR would it be more reasonable to leave evrything where it is and just Yank 2 tubes?

thanks ( I still do not have the functionality to upload a schematic my apologies)

[Jazz P Bass]

If no tube is installed in a socket, there is nothing in that circuit that will affect the other parallel tube.
Pull the socket / pull the tube. Same thing.

[tonefiend]

The Filter capacitors under the dog house appear to be 525volt 20uf caps (please see pic) The schematic looks like its looking for 600v capacitors? The Schematic actually looks like
it says 600p? ( I uploaded the schematic as a .jpeg) Im wondering if I can use
22uf 500v caps in this application? I like using F&T caps and thats the closest I can come using F&T caps which are 3.95 each, . Sprague atom 600v 20uf caps are 23.95 each x 6 caps.... Ouch!

[The Dude]

What is your measured B+? And, it would be good to check with tubes removed, as that will tell you max B+ in a "no tube" condition.

[Jazz P Bass]

22 uf/ 500 volt is fine.
They are in parallel.
There are kits available: https://www.amprepairparts.com/fendercapkits.htm

[The Dude]

......They are in parallel......

I'm not sure why that's relevant? Were you thinking series, like in a totem pole arrangement? At any rate, I agree that 500V caps would likely be fine. The reason I suggested measuring first is because this is a modified amp and we're not sure if the PT and power supply design is original.

[tonefiend]

What is your measured B+? And, it would be good to check with tubes removed, as that will tell you max B+ in a "no tube" condition.

First, I have to replace the 2 prong cord, with a 3 prong. Is it possible to take B+ measurements with bad filter caps?

The PT is original, and the OT is from a Fender Twin. As far as I can tell outside of that there has been no modifications done to the amp at all except for
the OT replacement.

[tonefiend]

22 uf/ 500 volt is fine.
They are in parallel.
There are kits available: https://www.amprepairparts.com/fendercapkits.htm

Thanks very much for the link. Do you know what "brand" filter caps those are for the 6G6-B circuit? I cant tell which brand they are by the pictures.

thanks again

[Enzo]

Your B+ is something like 450v? You don't need 600v caps, 500v would be fine. Don't waste money on the Sprague retro reproduction 600v tourist caps.

Your power tubes were/are paired up. You need one from each side. By side I mean where your output transformer has a brown and a blue wire, the brown wire goes to pin 3 of two tubes, and the blue to pin 3 of the other two. SO one tube on the brown side and one on the blue side. Just leave the other sockets empty. You get nothing for tearing them out other than the chance to screw up the wiring in an otherwise working amp.

[tonefiend]

Your B+ is something like 450v? You don't need 600v caps, 500v would be fine. Don't waste money on the Sprague retro reproduction 600v tourist caps.

Your power tubes were/are paired up. You need one from each side. By side I mean where your output transformer has a brown and a blue wire, the brown wire goes to pin 3 of two tubes, and the blue to pin 3 of the other two. SO one tube on the brown side and one on the blue side. Just leave the other sockets empty. You get nothing for tearing them out other than the chance to screw up the wiring in an otherwise working amp.

Great! Thanks for your input

Now I need to figure out how to put in a 3 prong cord properly, Then start on the re-cap

[Greg_L]

Great! Thanks for your input

Now I need to figure out how to put in a 3 prong cord properly, Then start on the re-cap

Check out "Uncle Doug" on YouTube. He is constantly tinkering with old amps, many of them being old Fenders, and three-prong cords and caps are always part of it. You'll learn a lot, his vids are great.

[tonefiend]

Does anyone know what Guage wire the power cord is in a Fender 6G6-B? I need to purchase a new 3 prong and the choices online are 16 guage, or 18 guage?

thanks

[eschertron]

Does anyone know what Guage wire the power cord is in a Fender 6G6-B? I need to purchase a new 3 prong and the choices online are 16 guage, or 18 guage?

thanks

Google "ampacity of SO cords" to find what 18ga and 16ga cords are rated at. I think either should be fine for your application. Usually it comes down to how mechanically rugged you want the cable to be.

Sounds like you have a great project there. Keep us posted!

[tonefiend]

FYI: I ordered the 18 guage 3 prong cord, apparently its easier to install the strain relief with 18 guage.