Ampeg GV-22

[Denton]

On a side note, the power transformer has a stamp of 682337, pt-113b, and 8930064. Would the 682 be the EI code and be a 73 date? That would be a replacement as well I suppose?

[Denton]

Having problems posting pictures, but I opened it up tonight. Orange is not used. Yellow ties into the jack and then the board. The green ties into the jack.

I assume this is wired 4 ohms.. And studying the speakers and the wiring still attached, they may have been wired parallel afterall. I was working fast and yanking stuff out so fast, I didn't take any pics at all. For some reason, I was thinking it was in series. So I guess it's wired for 4, and the speakers were wired for 4. The one was blown, so I need to still decide on a speaker(s). At least I can look for 8 ohm 12's.

[Hangman]

I assume they wired it for four ohms and then if you plug something into the ext speaker out jack it switches to 2 ohms. That would make sense anyway. But post pictures if you can and I can confirm that.

What about the black wire? Going to ground I hope?

[Denton]

I emailed you a pic Hangman.. Thanks!

[Hangman]

yep looks like its wired for 4 ohms, and switches to 2 if you plug another cab in.

the feedback resistor should probably be changed if they didn't already change it.
I think steelyman mentioned something about that too. he may have even gave a value.

-steve

[Denton]

Should the resistor be visible in that picture? I don't see anything in line with the yellow wire.. Or would it be on the board?

Sorry if I sound like an idiot.. I'm learning as I go. Thank you!!

---

Also, if the stock resistor wasn't changed, what effect would I have with the 15K vs the 27K on the 4 ohm tap? More or less distorted tone?

[Hangman]

It is on the board. The point that the yellow wire connects to should also have a resistor there. The solder joint looks original on one end of it from what I can tell. So perhaps it was not changed.
Although the other possibility is that they cut it out.

[Denton]

So I guess if it's clipped out, it will be a pretty gainy tone?

On another side note, I'm thinking about the Eminence GB-12's for this amp. Hearing great things about those speakers

[Hangman]

it would be on the underside of that circuit board.

[Denton]

So just an update as I now have been messing with it for a while. I put in a couple 8 ohm speakers in it and have been playing a bit with it. I just ordered a matched set of GE 6L6's and am considering a NOS 7199 as well since I'm replacing the power tubes. I have loaded it with vintage preamp tubes, including an RCA and Tele 12ax7 for channel 1 and 2 respectively. Ordering some Emi Legend GB128's this week as well.

Couple issues.. When I flip it on, I hear some weird swirling vroom sound for a second. It stops, and the amp runs quiet after that. Then when switching back to standby, it pops really loud. Any thoughts on reasons why it is doing this? Bad caps or something?