Signal on PI when volume is off?

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sonofmickel
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Signal on PI when volume is off?

Post by sonofmickel » Wed Nov 13, 2013 10:40 pm

I have an anemic 1987 build. It just does not have any oomph. All of my readings are great but I noticed that pins 2 and 7 on the PI have 11 volts dc when there is no signal going through the amp(all volumes are at 0). Is this correct?

The 1987 has a PPIMV that appears to be working fine. I have been trying to get the amp to "open up" for a year or so. No luck yet.

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neikeel
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Re: Signal on PI when volume is off?

Post by neikeel » Thu Nov 14, 2013 2:25 pm

Yes normal

What specs, whose materials, how about some pics?
Neil

sonofmickel
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Re: Signal on PI when volume is off?

Post by sonofmickel » Thu Nov 14, 2013 2:44 pm

I figured as much (normal for 11 volts on PI pins 2/7). I had just replaced a Weber OT for a Classic Tone, thinking the OT might be the culprit. So I get to thinking....maybe the Impedance selector is not letting the juice flow.

So I hooked up ONLY the 16 Ohm tap to the speaker jacks and it seems to be much more "open" sounding. It was late when I tested so the volume was relatively low, but the amp seemed much more responsive and "alive". I am ordering a new 3 position impedance switch now. I will report back any findings.

sonofmickel
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Re: Signal on PI when volume is off?

Post by sonofmickel » Sat Nov 07, 2015 12:50 pm

Concluding thread:
Swapping OT did not make any difference.
It's something else.
I have started a new thread with a complete rebuild of this amp.

I will update both or ask for this one to be shut down/removed.

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