DIY ACA mini

Received my "Almost clone board" about a week ago from the "Outside USA group buy".
Have been busy choosing other components than those listed on the BOM as many of them (7) were out of stock.
They were mostly resistors which are not critical as long as the same type, value and power rating is observed.

I did find a similar input capacitor at Digikey, an Epcos of the same size, material and rating, 495-4875-1-ND.
It should not be inferior to the Wima, but as a component obsessed audiophile, there is always a lingering, nagging suspicion...
Please advise...

As we have a small furry animal who is inherently curious, I wonder if there is any disadvantage in insulating the ouput transistors from the heatsinks to get rid of the +12V on them? A friend (?) of mine pointed out that if insulated, input capacitance would increase...
Is that really the case? And if so, does it matter? Could it decrease high frequency response?

:scratch1:
 
ACA Mini clone complete!

It sounds deliciously good! It’s really dead silent when not playing music. I prefer jumpers out. 😎

I attached some Makerbeam legs and plopped it on top of the ACP+. Open air goodness.

Thanks to Nelson, Mark Johnson, and Kevin Heem! This was a fun build. I am very pleased.
 

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Assuming that store management wants it, I will supply the boards and matched semis as a kit.

Estimated cost through the store would be about $30. I think it could be available next month.

We have someone standing by to create the optional "completion kit", although everyone is free
to buy the parts on their own or through group buys.

:snail: :snail:
Do the matched semis include the JFETs, too? That sounds too good to be possible.
 
I am planning on a mini open baffle (45 x 25 cm) with a 4 inch full range and 8 inch helper woofer to be driven by the ACA mini.

It will be miniature versions of my open baffles in the main system.

Searching the web for candidate drivers atm.
I'm using Markaudio CHR-70s in sealed boxes. F3 around 85 Hz. Plenty good for this use, I don't feel the need for a sub. They have a very clean and full sound. The bass is remarkable for their size and got better when I switched to the ACA Mini.

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