PDA

View Full Version : Which one is the phase inverter?

elkym
10-29-2008, 10:25 PM
I've got a Valveking 112. Just spent half an hour searching online... can't find anything...

Any general suggestions? Or does anyone have this amp and already know?
elkym
10-29-2008, 10:47 PM
bump

I'm going to bed soon... :(

I was hoping to get an answer before then...

Aah... Sel avi...
SatelliteAmps
10-30-2008, 06:18 AM
The 12AX7 closest to the power tubes.
Ace_F4i
10-30-2008, 07:42 AM
look for schematics and look to see which one supplies the power tubes
Ace_F4i
10-30-2008, 07:43 AM
or read the manual lol
elkym
10-30-2008, 11:15 AM
Schematics don't tell me which one is wired to the power tubes as I'm looking at the amp from the back...

If I look in the open back, there are two rows of tubes... Example, top down view from behind the amplifier is below (I've been told peavey's are a little weird with their preamp placement, so I'd like to be sure)

______o o
[] O O o []


the little o's are the preamps, the []'s are the trannies, and the big O's are the power tubes. I think it's the little o in line with the power tubes, but I'm not sure...
Rosewood
10-30-2008, 11:25 AM
If I was gonna throw a dart at it I think I would say the one next to the power tubes like most, and also the two preamp tubes are closer to the inputs and tone controls where they should be.
elkym
10-30-2008, 11:27 AM
K, thanks!
SatelliteAmps
10-30-2008, 07:44 PM
Same as I originally stated.

The tube farthest from the power tubes (closest to the input jack) is almost always the first preamp, and it goes in a linear fashion towards the power tubes. If it is two rows, then follow the row of 12AX7s (even if the go in a L fashion), and you will hit the PI tube.
Ace_F4i
10-31-2008, 10:50 AM
[quote=elkym;4947837]Schematics don't tell me which one is wired to the power tubes as I'm looking at the amp from the back...

quote]


the schematics tell you everything you need to know. just follow the signal path.. or use process of elimination if you don't know how to do that. V1 is always for the input. V2 will most likely be a gain boost or tone stack. Then from there just see what the function of the others are. The phase inverter will directly supply the power amp section.