I finished my first build, the ACA, and am really liking this amp.
As a complete diy audio newbie, I found the build fun and satisfying.
So now I am curious about the first watt kits on the DIY site. How do they compare to the ACA? I am powering a pair of ZU soul speakers, 101 db efficient or so, so low power amps seem to be the call.
If I was to try another kit build, which would you suggest?
I am mechanically inclined, but an electronic newbie, so I can build anything, but am a bit challenged with the electronic theory stuff.
KMF
As a complete diy audio newbie, I found the build fun and satisfying.
So now I am curious about the first watt kits on the DIY site. How do they compare to the ACA? I am powering a pair of ZU soul speakers, 101 db efficient or so, so low power amps seem to be the call.
If I was to try another kit build, which would you suggest?
I am mechanically inclined, but an electronic newbie, so I can build anything, but am a bit challenged with the electronic theory stuff.
KMF
For those speakers, ACA might even be the best.
Aleph J would probably be the next amp I would build for the speakers you have or if you wanted to experience something a bit different, then M2.
You could even do F4 without any gain. With 100dB speakers you won't need it if your source is a dac.
Aleph J would probably be the next amp I would build for the speakers you have or if you wanted to experience something a bit different, then M2.
You could even do F4 without any gain. With 100dB speakers you won't need it if your source is a dac.
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Wow.
this is getting interesting.
Love this site.
Thanks Nelson
If the definition of a good system is how much one is listening and toe tapping to the music, my system is doing great.
Two ACA amps in balanced mono powering Zu Soul speakers.
KMF
this is getting interesting.
Love this site.
Thanks Nelson
If the definition of a good system is how much one is listening and toe tapping to the music, my system is doing great.
Two ACA amps in balanced mono powering Zu Soul speakers.
KMF
As was done with the Pass M2x, the Pass Sony VFET amp offers four additional input stage daughtercards, on top of the Passworks-designed input stage daughter card. That one brings the total up to five. Not surprisingly, the Passworks input card uses Toshiba JFETs. Also not surprisingly, the four additional daughtercards don't contain any Toshiba JFETs at all. The plan was: give builders an array of options, without using difficult-to-source parts.
After seeing many dozens of M2x amp buyers decide not to build the best-sounding daughter card of the bunch, just because it contained surface-mount parts, the official VFET input cards here on diyAudio will have precisely ZERO surface-mount parts. The unofficial, friends-and-family-only, custom VFET input cards might or might not be a different story. Take me for a 45 minute flight in your airplane and we'll discuss ... at 4000' AGL.
After seeing many dozens of M2x amp buyers decide not to build the best-sounding daughter card of the bunch, just because it contained surface-mount parts, the official VFET input cards here on diyAudio will have precisely ZERO surface-mount parts. The unofficial, friends-and-family-only, custom VFET input cards might or might not be a different story. Take me for a 45 minute flight in your airplane and we'll discuss ... at 4000' AGL.
Sounds like this project is getting the full treatment - awesome! I’m hoping to see a line of bespoke, silver-plated, gold dipped, crypto-treated mounting hardware for those daughterboards in the store 😀
Wait till you see the DIY Sony VFET.
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I check the store daily.🙂 So many nice things to build, Thanks!
Russellc
Optional input stage daughter cards for the DIY Sony VFET amp. Bottom to top, their PCB-IDs are "S", "B", "M", "D" . Click on the image to remove foreshortening distortion. Eagle eyed readers may be able to spot my copy of Donald Knuth's books, volumes 1-3, on the shelf in the background.
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Thank you- Papa and Mark.
I’m excited! It looks like we are getting close to the finish line/ release date.
I’m excited! It looks like we are getting close to the finish line/ release date.
They are on the march.
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Bet we can squeeze those in a fairly small chassis
They are on the march.
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These look beautiful Nelson - can't wait!
Mark, I loved the daughterboard approach to the M2x, really happy to see you bring that to this project as well.
Thank you both for doing the good work (and to all those that have contributed)!
Bet we can squeeze those in a fairly small chassis
Wait till you see the special chassis that diyAudio has worked up for it.

I can imagine it will be awesome.
It would be cool if it looked something like the old Aleph Cube Chassis.
It would be cool if it looked something like the old Aleph Cube Chassis.
The marching vfets look like art🙂 A special chassis?!
This just changed my routine to checking the store daily twice now😛
This just changed my routine to checking the store daily twice now😛
It would be cool if it looked something like the old Aleph Cube Chassis.
That’s the first thing that came to mind.
Can’t wait to see them!
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