I might add if you want to put it in a case try to have a single ground to the case. To minimize any chances of ground loops. Star ground etc…The “naked” design has the “audio” ground floating in regards to other stuff…and the bottom PCB is to allow it to safely sit on top of stuff and have it out in the open.
That said you still want to be careful with the exposed amp even though there are no really high voltages etc…its still “on” and the heatsinks do get pretty warm.
Well we have had the ACP + now for over a month now and its setup to match 250-300 ohm headphones in impedance. I use it mainly for my Senn 650’s. I had the 600’s for a few years as a good low cost entry level gold standard. After trying the 660s and 650s my ears liked the 650 sound just a tad better so we sold the 600’s and kept the 650…
Along comes this new low cost, EXCELLENT Class A amp from Nelson Pass and when it became available at DIY Audio I jumped on it. It has been an excellent DIY project. No casework. Hard to really screw this one up…if u can solder.
I have never heard the senns sound as good as the 650 sound with this amp. Feeding with a Schiit Bifrost 2 (now sold) and now with a iFO Pro DSD multibit dac…its a 10/10…Solid. Bass like never thought possible with the Senn 650’s…
I had the Whammy as well, great amp, sold it as well…I love the ACP+ even more.
There are a lot of magic pairings and this is one of them. You can set it up for 32 ohms (the original design and kit setup) or set up with some resistors for almost any impedance. Or pick and intermediate impedance that works well with a wide range of headphones. Not liking compromises, I choose to set it up for senn 6xx’s.
This little amp can stand up to most any other amp well above its $200 price of admission.
You should run. not walk to:
Its one of those really great amps and a really great price
HIGHLY RECOMMENDED…and No I dont get any kickback here…just sharing the love!