JMP 50 replaced OT help

[Rasputin1176]

I have a 72 JMP 50 that had the OT replaced back in '83. It's a Drake 139 model but I've heard by a few who actually tested OT's in same amp that these are just not the same as the old Drakes.
Honestly I think this amp can be better sound wise.

I'm curious though, using the AC heater supply test on the OT (I know not super accurate). The primary impedance is only 3.2k. I've heard that's what many 80's 50w Drakes usually were??
Anyway since most repro are 3.5k to 4K even I think that's little too low, & this amp is very tough on tubes.

I'm placing an order for ****** either way I think it'll really improve this amp!

[syscokid]

I have a 72 JMP 50 that had the OT replaced back in '83. It's a Drake 139 model but I've heard by a few who actually tested OT's in same amp that these are just not the same as the old Drakes.
Honestly I think this amp can be better sound wise.

I'm curious though, using the AC heater supply test on the OT (I know not super accurate). The primary impedance is only 3.2k. I've heard that's what many 80's 50w Drakes usually were??
Anyway since most repro are 3.5k to 4K even I think that's little too low, & this amp is very tough on tubes.

The only numbers I have ever seen on the old Drakes is 3.4 & 3.5

I'm placing an order for ****** either way I think it'll really improve this amp!

Did you purposely omit the "Brand" name? Or this forum software protocol?

[Rasputin1176]

No I didn't, it auto hid the name. Let's just say it's 1 of the names that seem to come for Marshall replacement transformers. (Priest name from the Exorcist lol)

[syscokid]

No I didn't, it auto hid the name. Let's just say it's 1 of the names that seem to come for Marshall replacement transformers. (Priest name from the Exorcist lol)

OK, thanks. Mer..ren Audio!