here we go again - bridging ZV5

Please bear with me, this time it´s on direct order from NP
you should continue to try to bridge ZV5
So this time, if we collaborate, it will work?. Why bridged V5? The first time i tested NP´s ZV5 was right after it was published, at the time i was using my old Accuphase P300 wich is a pretty good amp, quick and dirty assembly of ZV5 gave something better, particulary in bottom end "clout" but with less power. Tried then to bridge, all attempts extremely powerfull but not staying DC out stable. My proposal this time is transformer split input,keeping the amp totally "floating". If You want to hang on here, be advised, this amp needs some serious cooling, fans are a necessity, if You participate, we will make a brutal beast, quite well groomed.

Nelson Pass

The one and only
Paid Member
2001-03-29 12:38 am
Did I say that?

Funny, I temporarily forgot what a ZV5 was, and while I was
looking it up I found "ZV5 with JFETs"


  • zv5 with jfets.jpg
    zv5 with jfets.jpg
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Nelson Pass

The one and only
Paid Member
2001-03-29 12:38 am
If you are using ZV5 with the IR-made IRFP9240's (the ones with
the mid-band gain shelf) then bridging them will give you lower
distortion because the 2nd harmonic they create cancels pretty well.

In actual testing with followers, you can get about the same distortion
figures with balanced circuits between the IR parts and the Harris or
Fairchild parts.

In any case, I think people are going to head toward making balanced
copies of the F5 for this sort of thing.