High VOltages on OA/OB after speedball upgrade

[Faris]

Hi All,

I have just upgraded my crack to the speedball. The voltage measurements of the stock crack (which had been running for two years) were on the higher end, but within the 10% tolerance.
After completing the speedball upgrade, the small board OA measurement starts out initially at 200V but then, within seconds, drops to around 110V and then slowly drops further, as low as 98V to 105V approximately, where it remains. OB behaves similarly, but with lower voltages, settling just above 90V after a while.
A2 and A7 read 0V.
IA/IB is stable at 181V, b-a/b is 0.
All LEDs are on.

on the large board, this is reflected as well. OB reads at almost 130V and OA at 120ish. B+ is 183V.
All LEDs are lit, tubes are glowing.

I am in the UK, so mains voltage accordingly.

Are these numbers something to worry about? I am especially worried about the initial spike upon turning on, as well as the discrepancy between the two sides.

I have already made sure all solder joints are tight.

Thanks in advance for any help!

Faris

[Paul Birkeland]

Can you post a photo or two of the build?

The OA and OB voltages on the small board are OK, but a little on the high side.  A new 12AU7 might be in order for you.  When the small board OA/OB voltages are brought down with a fresher tube, the OA and OB voltages on the big board will also drop. 

[Faris]

Thanks for the quick reply!
Here are some pictures. Is there anything in particular I should take a closer picture of?

imgur.com/a/zui9TLy

Thanks again,
Faris


edit: how do I upload pictures directly?

[Paul Birkeland]

Nope, those are OK.  The 2N2222 and TIP50 transistors need a lot more heat so the solder flows through the board to the other side, but that doesn't seem to have stopped your board from functioning properly.

[Faris]

Okay I will certainly reflow those just to be sure. Am I safe to run this amp until the new tube arrives? Will any 12AU7 tube from online shops in the UK do, or is there a recommended brand?

Thanks again for the quick help.

[Paul Birkeland]

Sure, you can run the amp.  Any 12AU7 will do!