Pictures of your diy Pass amplifier

I should add that this (ACA) amp sounds wonderful. I have it powered with a 24v Meanwell power supply and it's hooked up to my Fusion-12 Tempest speakers and there is plenty power to spare. Also had it hooked up to my Nola clones and it is at home with those as well. I am currently running it from the pre-outs of my old Denon AVR for the bass management capability for the subs I use along with all of this stuff.

Very nice amp, indeed. Hat's off to Nelson Pass for sharing this. I had a great time building it and will certainly use it from here on out.
 
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Mystery from 2008/9

I dug this out of my junk box but don't remember what it was. It's dual rail (+/- 9V), the caps are 10uF and the jfets are 2SJ108GR - pair of them per side. It's definitely not JFET BOZ but I can't remember what it was.

Maybe MPMarino or Dennis might remember but I'm certain it's from NP's brain. 20180418_101745.jpg
 
SONY JFET 2

Hi,

Not as good a build as some but here it is anyway, very nice sound, also attached is the previous amplifier which is a sort of Nakamichi PA7 lite, so I guess it almost earns a place in a NP build picture. Compared to the class A bipolar, I guess I prefer it, I can listen to both but the class A is a little bit more "hi-fi" sounding, The JFET has a little bit more "boogie factor", "funk", "je ne sais Pass"?
 

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First I would like to thanks Mr. Pass for the permission using the PASS Logo for the Front plate. Been busy for the last few months. The VFET boards itself have been soldered back in 2016 when I got my set from the first batch. Until now planning for the enclosure as well as my main work as a MD took a lot of my time from starting the build. Until yesterday when I started milling and drilling...

Finished front plate and started the side plates with heatsink and bracket mounting as well as for the transverse struts to stiffen the whole construction.
Front is milled from 25mm and sides are 15mm aluminium.

Still waiting for the bigger CNC machine to make the bottom and top (5mm)




 
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finally finished

Hi,

Had some time en budget available, time mostly. Remembered i had working prototypes for the Alep-j and Aleph-x hanging around in storage for more then 10 years now and decided to finish them. Front and rear panels are the same for both.

The aleph-x is dual mono. Had the trannies left over from my attempts at the Hiraga le classe 20 years ago. Caps are standard Nichicon LGU 22.000uF/35V so 132.000 per channel in the psu. Schematic per Grey's original, sounds nice :)

The aleph-j uses a single psu with the same caps. I was not very hopefull for this one as i remember not liking the prototype much. Now i like it very much.

Perhaps i Should revisit the Hiraga and the F5. My wiring must have improved because there is no discernable humm or hiss with my ear close to the drivers. Happy with these.

Greetz Joris
 

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