Just finished a Lightly balanced Zen

[yggdrasil]

I started this project in the winter of 2007. After having read through the Zen articles I wanted to start with the Zenlite, and do the balanced one since I had already done the Bosoz.

In this amp there are some recycled parts. All the sockets have been recycled from old lamps. The power switch is a recycled switch that was installed in our house in 1957.

After having built the first channel it was time to find light bulbs. This should probably have been done first, because I could only find 40W and 60W bulbs at the local store. By accident I found 100W bulbs at another local store this winter, and the project could continue.

I built the circuit in figure 16 with no changes. The power supply has a 500VA 40-0-40 transformer and the suggested CLC (25000uF - 5mH - 25003uF) unregulated supply, giving ~60V.

Each MOSFET in the amp has two bulbs in parallell for bias current, giving ~2A to each MOSFET.

The amp has been in use a couple of weeks driving the mid/high section of my speakers, and I think it is absolutely gorgeous. And it is dead silent with absolutely no audible hum/noise on 100dB sensitive speakers.

I have not done anything to make it look like it deserves. Wooden box for the power supply with the heat sink attached to one side. Heatsink is ~0.4C/W. I have no trouble holding my hand on it after 2 hours.

[yggdrasil]

The power switch...

[carpenter]

switch to heat-lamps for winter use!

Thanks for reviewing the sound quality. I've always wondered how that fellow performed.

[Magura]

Thats what it's all about!

Make an amp, see what it's good for, perhaps tweak it to adapt it a bit, gain experience, make another amp.........

That is according to my opinion, best done by not wasting too much time on shiny boxes and searching for butique parts.


Magura

[carpenter]

Originally posted by Magura
Thats what it's all about!

Make an amp, see what it's good for, perhaps tweak it to adapt it a bit, gain experience, make another amp.........

That is according to my opinion, best done by not wasting too much time on shiny boxes and searching for butique parts.


Magura

Aaaaah, but I like those pretty boxes, too...

[Zen Mod]

Originally posted by carpenter



Aaaaah, but I like those pretty boxes, too...

but - you don't need amps now , when you have Spice ..... to play with .....

[carpenter]

Originally posted by Zen Mod



but - you don't need amps now , when you have Spice ..... to play with .....

Stepping off-topic for a second. (sorry)


You know, you really did hit the nail on the head... With regards to the creative process, my brain doesn't care whether I'm fabricating an amp, or designing (OK, grappling with in my case) a new slant on Nelson's schematics. As long as I'm listening to something I've built in the past, the future can wait while I play in the spice-box.

BTW Choky, thanks for offering up that LUAX schematic the other day. I'm learning a bunch about CCS layout.