Ampeg V4 distortion knob vs Early model

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mad scientist
May 25, 2008
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Brooklyn
I have an ampeg v4 distortion knob amp. It was beaten up and spray painted by others. I was looking into get a tune up, changing to a grounded plug, maybe putting in a fan and definitely putting in a fx loop.

Now I'm reading it isn't the same thing as the early non master volume and or non distortion model. That those are way cooler and have a totally different schematic. So before I go modding this one, that I haven't had a chance to play with a lot yet, should I sell it for an earlier model?

How different are they? Is it apples and oranges or apples and apples of a slightly different varietal?
 
Channel 2 on the distortion model is closer to the preamp arrangement of the standard V4, it's 12AX7 > gain > 12AX7 > tone stack/reverb.

The first channel uses a 12DW7 (AU7 side) > distortion A > 12DW7 (AX7 side) > distortion B > volume > tone stack.

The midrange on a standard V4 is driven by a 6K11 which is three triodes, the midrange circuit on the distortion model is a simplified design using only half a 12DW7.

The phase inverter design is different. Floating paraphase in the older V4 and cathodyne in the distortion model.

Short version - try just using channel 2 and it would probably be closer to an older V4 than the distortion channel.

If you're going to mod one either way, mod the distortion model. Less lost value that way.
 
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