VVR3 enhanced TW

[harryk]

I have installed both fixed bias and cathode bias VVRs to many amps by now and fixed bias version to two Plexi Lead clones. In the other version the whole amp has been scaled and the other has only power tubes scaled. With this experience I personally prefer scaling power tubes only. Only in the case when you go to B+ voltage of 30-40 volts and your PI is hitting power tubes with some 20-30 volts AC swing, you get some really nasty distorted sounds related to very low B+ voltage. VVR is not the best tool for bed room levels, but as Colossal mentioned, it can decrease big amp noise level to the point where you can live with. If you are interested in to hear some sound clips of my Plexi Lead with VVR only in power tubes, go to my website www.bluetone.fi and listen to Bluetone Plexi Lead clips. There are three different versions. One using amp without VVR, one with VVR in 12 o`clock and one VVR in 9 o`clock. Harry

I just listend to your clips. Are you using a master volume also with the VVR? It looks like you mention a master volume at 5:00???

Sounds great

Yes. There is a PPIMV in this Plexi Lead amp. I have the other Plexi without it and not aiming to add it in the first hand when I change scaling system to power tubes only. To my mind VVR is best when you do not have to take it to bed room levels but to get a reasonable noise level with good sounds when playing with band. Adjusting three different controls (Volume, PPIMV and VVR) makes life more complicated to older people like me (53 years). The ultimate set up could be an amp with only one volume and tone control with killer sounds and reasonable noise level. Harry

[BigFun3]

When I have implemented KOC's version, I tried whole amp and power section only scaling +/- MV. By far I preferred power section scaling with a MV used not as a MV, but rather to REDUCE overdrive....kinda backwards to what most folks use MV for.

Anyway, a good PPIMV (dual-ganged) allows you to keep the preamp juiced for a wider dynamic range and more explosive transients while not clobbering the back end when the wick is trimmed a good deal. Sounds great that way.

BF3

[Tonegeek]

When I have implemented KOC's version, I tried whole amp and power section only scaling +/- MV. By far I preferred power section scaling with a MV used not as a MV, but rather to REDUCE overdrive....kinda backwards to what most folks use MV for.

Anyway, a good PPIMV (dual-ganged) allows you to keep the preamp juiced for a wider dynamic range and more explosive transients while not clobbering the back end when the wick is trimmed a good deal. Sounds great that way.

BF3

My experience exactly with a BN 18watt IIb + VVR + PPIMV. Its a great mod.