ACA Mini Essentials Kit

Thanks to Papa's generosity, we can build this amazing amp with his hand-selected and matched essential parts. What a bargain! It has displaced my 50 wpc Millett NuClassD as my new my desktop amp.
Note that the power switch is really a standby switch, so if you have a tube or other preamp you want to power down along with this amp, you will need a way of switching off the ACA Mini's SMPS to prevent a 'thump' in your speakers when the preamp is powered back on.
I elected to do this by adding a power switch to a version of Mark Johnson's SMPS filter design I had as a separate device. The 'off' side of the SPDT power switch also takes the Mini's power caps voltage down to ground via a bleeder resistor in about 5 seconds.

The performance of ACA Mini comes as a most pleasant surprise - but then again, not really. Coming from our friend and generous contributor, Nelson Pass, the ACA Mini truly delivers with outstanding performance. Coupled with the also magnificent Korg Nutube B1 preamp, the amplifier projects a solid soundstage of width and depth, creating a realism within the music which belies the diminutive size of the amp footprint and component count. Clearly, Nelson's pursuit of the First Watt principles are demonstrably manifest in the ACA Mini.
Thank you, Nelson.
Thank you also to the DIY Audio Store team who take such good care in completing our purchases.
There is little more to say beyond my strongest recommendation of this amplifier. A straight forward build with a caveat to ensure that Nelson's excellent note is carefully followed on the crucial process for the bias settings. There will be no issue with this process if the designer's clear instructions are respected.

Once again the ACA mini as a kit with essential kit components
At all documentation descriptions 5 stars ⭐️ ⭐️⭐️⭐️⭐️

I’ve build this amp over the past weeks, sourcing the PCB kit from DIY Audio store and the other parts from DigiKey and other sources. The parts kit was sold out at the time.
I bought a LRS 100-24 to embed the power supply in the total package and used an SMPS DC filter because off the good reviews. Based on what I hear, it certainly doesn’t hurt.

I have 2 ACAs that I use in bridged mono and everyone knows (or can read) what that delivers in sound quality.
I’m therefore so happily surprised about the sound quality off this little amp. In certain ways, it delivers more details or maybe dynamics than the ACAs do.
I would have to do more listening sessions switching back and forth to know. But not doing that right now. Just enjoying what I hear :)

amazing quality A++
from a 30 year + experienced audiophile / DIY builder

If you're reading this, you are curious about this little amplifier. Build one (or many)! You will be amazed. Make sure all transistors are soldered where they should be, take your time to set the bias--and enjoy! The sound is amazing with plenty of bass. Cheers!