New 18w Build Suggestions Please

[pryde]

Hello everyone.

I came across one each of an 18w Lite iib and a 18w TMB turret boards (made by Watts Audio)

I plan to build just one of these and would like to stay with the lite because simpler it better for the most part. BUT, I would like a "decent" master volume solution for the Lite if possible? I have heard typical master volumes don't work well with the Lite circuit but would like opinions from folks who know the circuit good and maybe came up with a decent solution. Is power scaling the only good option? Is it because of the parallel V1 design?

I appreciate your thoughts on some mods to get some lower volume crunch.
Thanks

[M Fowler]

There are so many versions out there but what your talking about is Dockery's Lite IIB with master volume.

[xtian]

I agree that the cross-line MV sucks. I like the PPIMV much better. But neither is great on 18 watt amps, IMO.

[M Fowler]

Yeah my favorite 18w video is by Greg V, it has PPIMV

https://www.youtube.com/watch?v=EBvHr0YlFPA

[pryde]

Thanks
So the LarMar PPIMV would be the way to go with the lite iiB circuit?

[MHProd]

I tried ppimv and the VVR in several builds. It worked "ok" but there was always some sort of compromise to be made since it would always degrade the sound somewhat. If you have more than one amp or want to build more amps in the future, save some cash and invest in a Torpedo Reload. It has a bunch of features you probably won't need but the attenuator part alone is worth it.
It has a unique design that nobody else comes close to doing. It's been my best purchase in the last 15 years easy. Not cheap, but totally worth it.

[pryde]

I tried ppimv and the VVR in several builds. It worked "ok" but there was always some sort of compromise to be made since it would always degrade the sound somewhat. If you have more than one amp or want to build more amps in the future, save some cash and invest in a Torpedo Reload. It has a bunch of features you probably won't need but the attenuator part alone is worth it.
It has a unique design that nobody else comes close to doing. It's been my best purchase in the last 15 years easy. Not cheap, but totally worth it.

Thanks for the suggestion but wow that is to rich for my blood.

[pryde]

Yeah my favorite 18w video is by Greg V, it has PPIMV

https://www.youtube.com/watch?v=EBvHr0YlFPA

Thanks. Is the 1M dual-gang necessary for the 18w? I have a couple 250k duals around from another build I did a while back.

here is the PPIMV I am familiar with:

[M Fowler]

I would at least go with a dual 500k pot to replace the two 470k resistors your removing from the board.

[katopan]

Any of the Lites are a totally clean preamp and all the distortion comes from the power valves. A PPIMV in an 18 Watt acts as a drive control and acts to clean up the amp. This occurs even in a TMB, although with that variant it is possible to get preamp distortion only (but it sucks with mixing it into power amp distortion).

The best solution for an 18 Watt is VVR applied to the PI and PA only (the preamp isn't scaled, but kept at full normal voltage by it's own separate parallel power node with a larger than normal power chain resistor. This is all well documented at 18Watt.com.

Or shell out for the attenuator of your choice and burn out your power valves at the same rate as you would playing at full volume on stage.