Thanks everyone! Dennis, check out post 5918 in this thread. You’ll find a bit more porn there 
Re chassis size: these are an AliExpress purchase that I’ve slowly customized. I believe the sinks are equivalent to a 5U/350. I’ve got limited space and I liked that the enclosures themselves were narrow compared to your average stereo chassis. Lots of planning and measuring before the final assembly In fact, since those pictures were taken I’ve managed to squeeze 50uf Ducati motor runs into each channel.
Re chassis size: these are an AliExpress purchase that I’ve slowly customized. I believe the sinks are equivalent to a 5U/350. I’ve got limited space and I liked that the enclosures themselves were narrow compared to your average stereo chassis. Lots of planning and measuring before the final assembly
In fact, since those pictures were taken I’ve managed to squeeze 50uf Ducati motor runs into each channel.
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F3 on diyAudio UMS Mounting
My F3 is nearly finished, and I had a lot of help along the way. Thanks to: Jeff Young, Randy Thatcher, adason, wg45, woofertester, and of course Mr. Pass.
The amp sounds great, I think clearly lower distortion than the F1J, F2J and BA3 that I have built. Next I need to build some speakers that are more suited to this amp than my FE206 Vulcans and my very low impedance (2 ohm minimum) three ways.
Sorry for the low quality pictures from my phone.
My F3 is nearly finished, and I had a lot of help along the way. Thanks to: Jeff Young, Randy Thatcher, adason, wg45, woofertester, and of course Mr. Pass.
The amp sounds great, I think clearly lower distortion than the F1J, F2J and BA3 that I have built. Next I need to build some speakers that are more suited to this amp than my FE206 Vulcans and my very low impedance (2 ohm minimum) three ways.
Sorry for the low quality pictures from my phone.
Attachments
Without a filter to shape the frequency response there is far too much treble on the Fostex. I am sure I could add a filter that would make them a better match, but I really like the F1J/FE206 combination because of the bass boost that the current source amplification provides that speaker. I think the F3 will be great with something like Troels Faital 3WC-12 or driving the top end of a more traditional 3-way 8 ohm speaker.
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Thanks Chas. In my cave system it will probably drive the fullranges on SLOBs, and the alternative would be the F1 (non-J) but I think that F1 would work better with my 127 or 103
I wanted to use the Nichicon Muse caps for coupling the output, and the largest size available is 1000uF. The output of the F3 needs ~15,000 uF. See post number 2 in the F3 Builders Thread.
I used the Nichicon Muse UKZ caps instead of the Silmic's because I have had good experience with them in the past.
All those parts sound pretty good to me. Probably the most
contentious part is the big electrolytic at the output. If you could
parallel up a pile of Elna silks or polypropylenes to form the output
capacitance I think that would be the biggest improvement you
could make parts-wise.
Yes, I can see it now.... 100 parallel Solen canisters per channel...
I used the Nichicon Muse UKZ caps instead of the Silmic's because I have had good experience with them in the past.
Nichicon's got that gold coat, boosts the bling factor I used the same ones for my Burning Amp 3 build, although the turned out to be a bit big for the input board. Even put a pair of them as the power supply caps on a DH-220 I restored 
(didn't know as much then, would have used something cheaper today)
You could always go with film caps! I can just see a wall of axial film caps in rows. Maybe it would have to span multiple boards?
I used the same ones for my Burning Amp 3 build, although the turned out to be a bit big for the input board. Even put a pair of them as the power supply caps on a DH-220 I restored (didn't know as much then, would have used something cheaper today)You could always go with film caps!
I can just see a wall of axial film caps in rows. Maybe it would have to span multiple boards?
