Help With Provenance: Pass Labs Zen

[Zen Mod]

Dennis asked that you see all mosfets and write types of them here

 

[Dennis Hui]

The Zen article showed IRFP240/140/040 giving different levels of distortion so
I'm curious what is used in this sample.

 

[SiliconTi]

Other MOSFET is an IRFP140:

 

[moe29]

That's a pretty cool pick up for next to nothing. Well done!!!

The CLC PSU works well on my Zen amp - definitely an improvement over the first version.

Thanks for sharing!

 

[SiliconTi]

Just to clarify: the ad I posted IS NOT for the amp I bought, it is for one that sold a few years ago. It was just an example.

 

[Dennis Hui]

Other MOSFET is an IRFP140:

View attachment 914217

Thanks!

 

[SiliconTi]

Ok, testing time!

I pulled out my "sacrificial" equipment just in case

Using Pioneer SP-BL22-LR speakers (6 Ohm, 85db) and a Schiit Fulla DAC.

Conclusion: WOW! Very nice, very powerful with well controlled sound throughout the audioband.

I think I'll either laser etch the face plate or (more likely) create a nice sticker set to make it look a bit more "official". Oh, and a power-on LED too.

 

[brianco]

IF I were you I would simply put a label on the back (paper) given its known history and the probability of its being an original prototype. If it is indeed an original prototype any fixed label would deface it IMHO.

 

[SiliconTi]

Yeah, I'll make a sticker that could easily be removed without damage. Same with the LED - nothing permanent.

 

[SiliconTi]

Well, I finally have this installed in my primary system. Using my Quicksilver Line Preamp, a Mytek Brooklyn DAC for DAC and phono input, Nak RX-505 for tapes, Dual 1219 for TT. Speakers are Klipsch Heresy III.

It sounds outstanding. I like it better than my McIntosh pre/amp.

 

[SiliconTi]

BTW: I left it as is. No sticker, no LED.

 

[brianco]

Delighted for you...

Should any problems develop they can soon be sorted by the (AL)mighty ZM on the appropriate thread!

 

[SiliconTi]

Also, as a side note, my unit appears to be a "Zen (revisited)" version with the pi network on the powersupply.