PPIMV on a Rocket

[andrew]

Has anyone tried a PPIMV on a Rocket type clone?

[908ssp]

Well it is my opinion that any master volume on a TW circuit is a mistake. The basic architecture and design requires the power tubes to be driven as hard as possible which makes a MV impossible. Attenuators or possibly Power Scaling is your only solution.

[rfgordon]

I'd have to concur with Alex. I've tried PPIMVs on a coupla different Wreck-style amps. My results are that a Wreck is sort of binary--all on or not. I think they're kinda like Formula 1 engines--nothing much happens below about 15,000 RPM!

[andrew]

Thanks guys. It saves me from wasting shipping on a $2.50 ganged pot!

[Mark]

Dear Andrew

You made the right decision, from my experience the Express/Liverpool amps are all about driving the output stage into distortion.

Regarding the Rocket, for your own curiousity try the Matchless style master volume, but I don't think this is the amp to do it to. Perhap try a 15/30 watt switch.

[johnspeck]

I have a 15/30 watt switch on my Rocket, and it's not much of a volume drop. Actually, I don't really like it, because driving the speakers harder with more output seems to give a more 'full' sound; more bass and grunt.

My suggestion would be an attenuator. Hairyandy has compared a Hotplate to his newly finished DIY Airbrake. He says it sounds better, more transparent.

[Mark]

Dear John

I take it that you mean the DIY Airbrake sounds better than the Hotplate.

I have 50 watt Mass that is okay, though my Boogie SOB that I converted to a Mark 1 doesn't like it.