vvr question

[bigsmitty]

I'm getting ready to install Danas vvr in my champ, is it better to regulate the whole amp or just the power amp? Which way gets more overdive?

[Kagliostro]

Many people like to regulate only the final tubes and the phase inverter

consider to add a PPIMV (Larmar ?)

Kagliostro

[dartanion]

The Champ is single ended and has no PI. Not to say that you can't use a PI in an SE amp, the Champ doesn't.

Scaling the whole amp works quite well, however you can keep the preamp drive level higher with only scaling the PA. A master volume after the driver stage helps to dial in the amount of drive from the preamp.

[FYL]

I'm getting ready to install Danas vvr in my champ, is it better to regulate the whole amp or just the power amp? Which way gets more overdive?

A champ has only two and a half gain stages (the half is the power 6V6GT). You can't reach OD with only two gain stages but will get nice disto.

If you fancy preamp disto, use the VVR for the whole amp but be aware that some grid current can appear at the lowest settings - you have to add a coupling cap at the input. If you fancy power tube disto, just use the VVR for the screens and plates and add a master volume between the second 12AX7 section and the 6V6GT.

[dartanion]

I'm getting ready to install Danas vvr in my champ, is it better to regulate the whole amp or just the power amp? Which way gets more overdive?

A champ has only two and a half gain stages (the half is the power 6V6GT). You can't reach OD with only two gain stages but will get nice disto.

If you fancy preamp disto, use the VVR for the whole amp but be aware that some grid current can appear at the lowest settings - you have to add a coupling cap at the input. If you fancy power tube disto, just use the VVR for the screens and plates and add a master volume between the second 12AX7 section and the 6V6GT.

You can avoid all the DC blocking caps at the input by changing the lower limiting resistor from a 100K to 220K or above.

[bigsmitty]

I'll probably have to try it both ways and see which one I like better.

[FYL]

You can avoid all the DC blocking caps at the input by changing the lower limiting resistor from a 100K to 220K or above.

That's what I thought and posted eons ago but some 12AX7 are still problematic.

[Masco]

Many people like to regulate only the final tubes and the phase inverter

consider to add a PPIMV (Larmar ?)

Kagliostro

Just so others understand -the reason one would regulate the PI is so you don't have to use a PPIMV.

[Kagliostro]

Sorry

When I read I was inattentive and missed you wrote CHAMP

Kagliostro

[bigsmitty]

I think I'll try the whole amp first rat shack didn't have the in4007 diodes you need to do just the power amp. I would like to try just the power amp though, sounds like you could get more drive that way.

[bigsmitty]

Tried it both ways I like regulating just the power tube on the champ better, regulating the whole amp its still clean with the vvr down, the champ doesnt have enough gain to overdrive. Regulaing just the power tube gives a nice overdrve. Thanks to mcracer for the diodes!