Further adventures of Zen v4.....(questions)

[cadaverdog]

O.K., I picked-up my heatsinks and cover plates from the machine shop (they're beautiful btw)- and I began doing some fit-up on the chassis...................so

1. I was wondering just how far to keep the toroids from the gain circuitry. I'm asking this question because I want to build a single stereo amp instead of the dual-mono's I had originally planned on (the wife acceptance factor is quite low.) Anyway, I will not have the chassis space for a 10" clearance (x-formers to pcb) like I would have had with the monoblocks; suggestions??

2. Speaking of the toroids, I've decided to go with two 18+18v 250va Avel-Lindberg transformers (one per channel.) I want to do this because the difference in price is enormous.........suggestions??

3. Can the Zen v4 be driven by a triode preamp? I know there are some impedance issues, but I'm not sure.

Thanks in advance!!

[kilowattski]

Just Isolate it similarly to what I have done with my version of the Zen IV. Have a peek at these threads to see what I am talking about.

Zen IV Progress Report

More Zen IV Progress


As you can see, the power supply is below and shielded from the amplifier and signals mounted above. Just an idea for you to ponder. I hope it helps.

[Panelhead]

Originally posted by cadaverdog
O.K.

3. Can the Zen v4 be driven by a triode preamp? I know there are some impedance issues, but I'm not sure.

Thanks in advance!!

I found it to be very hard to drive for bass and dynamics. Something to do with the transfer function.
I inially drove it with a 6080 tube linestage. This idled at 80 ma per channel.
The 1 ufd caps used seem to roll the bass above 50 Hz. Placing some 12 ufd caps there gave it a proper dose of jump.
But I ended up driving it with the Steve Eddy designed Tao headphone amp. Just idled it down a bit.
Bumping up the current through the input buffer on the V4 helps some also.
The circuit does not look to be that hard to drive, seems like the input impedance on mine was 36K or so.

George

[Nelson Pass]

ZV4 has a 47K input impedance, so it's hard to imagine
that it wouldn't be drivable by a triode. It does have
relatively low voltage gain, though, and needs a couple of
volts to reach good listening levels.