Dual OTs & PPIMVs for Low Volume?

[The New Steve H]

I built an amp with two OTs. Each OT has its own PPIMV. I originally intended to have a single OT, but I needed two because I screwed up with the impedances. It's set up now so each PPIMV turns down two of the four output tubes.

Here's my question: is there any point in using two separate OTs and PPIMVs, generally? I'm wondering because it seems like this system might give better sound at low volume. You can turn one PPIMV down to nothing, and you would not have to turn the remaining PPIMV down very much to reduce the loudness, so it might have a smaller effect on the quality of the sound.

I know a lot of people don't care about low-volume playing, but I hate getting into gunfights with my neighbors.

[dcribbs1412]

I built an amp with two OTs. Each OT has its own PPIMV. I originally intended to have a single OT, but I needed two because I screwed up with the impedances. It's set up now so each PPIMV turns down two of the four output tubes.

Here's my question: is there any point in using two separate OTs and PPIMVs, generally? I'm wondering because it seems like this system might give better sound at low volume. You can turn one PPIMV down to nothing, and you would not have to turn the remaining PPIMV down very much to reduce the loudness, so it might have a smaller effect on the quality of the sound.

I know a lot of people don't care about low-volume playing, but I hate getting into gunfights with my neighbors.

Sounds interesting...what circuit is this based on?...any pics ?

Darin

[Reeltarded]

omg I have a headache..

What is the circuit? Is it LTPI? I wouldn't think to use dual PPIMV, I would use a single 50k/RL pot in series with the PI feed to keep it simple, 'cause I am stupid, and simple works great.

[Zippy]

Sounds like there is some crosstalk between the two output channels. You can test whether this is true by comparing your system as-is with pulling two of the output tubes. I'm betting that turning down one PPIMV is loading the other side.

There is usually not that much difference between playing with two vs four output tubes at low/medium volumes.

I hate getting into gunfights with my neighbors.

Me too - too damn noisy and I only have a knife.

[The New Steve H]

This thing is a 5F6A with a Little Wing output section multiplied by two. Everything up to the coupling caps on the output is 5F6A, with a couple of resistor values changed.

I don't know how crosstalk came up. The amp sounds good. Did I miss something?

[Reeltarded]

Little wing... Did I tell you about the amp I built with a bird based master volume?

Sorry, I swear not one more animal circuit joke from me.

[Zippy]

This thing is a 5F6A with a Little Wing output section multiplied by two. Everything up to the coupling caps on the output is 5F6A, with a couple of resistor values changed.

I don't know how crosstalk came up. The amp sounds good. Did I miss something?

Excuse the vernacular use of the term - did you read the rest of my post?

[Reeltarded]

PS: Zippy is refering to the condition where the PPIMV is very low (normal amp not your siamese OT freakshow) and the amp is driven hard.

The PPIMV set below about 7 makes a loading situation that brings out a nasty thing in the throat of the tone that some people claim to like. The PI breaks up WAAAAY more.

If you have 2 PPIMV maybe it's doing something you haven't detected yet. (is what he may be saying)

Zippy, I don't think Steve might be aware of that loading thing.

Tune in next time, to Amp Court.

[The New Steve H]

So we're talking about something that MIGHT be going on. I can take a look.

I don't really use it with the master below about half, so I don't know much about how it sounds when it's adjusted that way. You have to turn it almost halfway up to be loud enough to enjoy practice.

[Zippy]

So we're talking about something that MIGHT be going on. I can take a look.

Since we can't SEE your circuit, we can only conjecture. It wouldn't be the first time you've made something "interesting"...

[The New Steve H]

It wouldn't be the first time you've made something "interesting"...

The JTM45 kit was almost normal.

Well, apart from stuffing the wrong PT in it and machining a new base from scratch.

It hasn't caught on fire yet.

[Reeltarded]

If the internet were a card table I would have flipped it over on you at least 10 times by now.

Stop being different, you damned pioneer!

You and your stone wheeled warp drive! I swear! lol

[The New Steve H]

I got stuck with the JTM45! I swear! Although I did want to stick a PPIMV on it.