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Looks and sounds incredible. The kit is no longer available, so I had to source the parts from several different suppliers. I highly recommend this amplifier. Thanks Nelson and DIY Audio.

Product was exceptionally high quality and perfectly manufactured. It made the installation of the volume control quick, easy and professional looking! Well done!

great amp, fun to build as well. I wish there is an official case option as in noir.

I'm really enjoying putting the amp together. I've made a few mistakes and had to buy an additional parts package. I purchased 2 amps. I know the second amp build will be quicker and easier to build after I have the first one under my belt. I'm planning on setting up a monoblock.

Yesterday I finished the creation of the crossover. Excellent product, even if I am now in the development phase I already have good satisfactions.
Highly recommended.
Thanks to you and Mr Nelson.
Best Regards

I haven’t had a chance to set the bias yet, but the led lights up. Seriously, if it has as much quality as the regular ACA,( I built two for monoblocks) or the B1 preamp, I’m sure I’ll be happy.

This pc board is a perfect solution for helping prevent heat and mechanical damage to the potentiometer. The board provides either screw down wire clamps and direct soldier of the wires to the pcb,

Without any formal knowledge, extended experience or measuring instruments, my impressions are that this little amplifier reaches way lower in the bass region as well as the high frequencies without a roll off. The sound is full and complete. I am excited anticipating how it will sound after some use. The kit is simple and easy to build. Would suggest two multimeters for the biasing - makes it easier. The kit was flawless (as always), the build guide by 6L6 was excellent and we must thank Nelson Pass for his generosity to all of us. If you are thinking about building this amplifier, please don't hesitate! Highly recommended!

What a stunning pre-amp!!! Using it to drive my DIY Wolverine amp and what a combination, warmth, clarity, tight bass….absolutely amazing!!!

I built monoblock Aleph 2's with this chassis using the Aleph UMS boards available on Etsy. The case works great for that application. The chassis can dissipate a good amount of heat and is pretty big for the price. I have used the 4U, and these 5U cases as well as Aliexpress cases. They all have their merits. The Aliexpress cases that I have used have fancier machine work (as a stock option) but the anodizing isn't as tough. Also, you have to do a lot of work drilling holes etc. These 5U cases, you just put them together and bolt your boards in. The only drilling that is needed with these is to bore out the hole for whatever transformer you are using. Otherwise, just go to town and get your amp going. :)

I built these Aleph 2's for a friend who opted to have the fronts machined which was very nice. There was a lot of back and forth with the chassis manufacturer and my friend to settle on a design.

It would be good to have a general instruction video for a new builder. Other than that, everything is pretty good.

I apologize for the delay in this mine, I am completely satisfied with the kit purchased and also with my previous (far) purchase of your F5 kit. True, many hobbyists struggle with being able to make their own PCBs or being able to sort and match semiconductors for lack of the proper equipment. I thank all the diy community who worked to produce all this, not least a special thanks to mister Nelson Pass for his availability towards the community of hobbyists and DIYers. Best regards

Just finished my two mono blocks and was totally amazed that a single ACA would easily drive a pair of large advents (~86db sensitivity) in our small music room. Absolute jaw dropper and dynamic wide sound stage. I only drive one pair of Advents, while the Sansui drives the other pair and paradigm speakers.

Genuinely, thank you all for your experiential knowledge and support...

Easy to build with a clear head and no distractions... Yes!

Easy to build with instructions (v1.8) from website. Took about 6 hours over a couple nights to build, taking my time. Based on forums biased to 12.5V. Sounds great! It's impressive with efficient speakers (Klipsch RP600m; DIY open baffle speakers with Lii Audio Fast 8 drivers). I used Luminous Audio passive preamps.

This was my first successfully complete kit. It was very easy to assemble and provided a great learning experience. The success inspired me two try building the amp camp preamp. That was a successful project also. I have mounted them both on the bottom plate of chassis hat I’m modifying to enclose and protect them from curious fingers. After the chassis is done I’ll be looking for another project. This has been and fun and truly rewarding experience.

Just wanted to add some thoughts regarding WHAMMY as a PreAmp for F6 (powers Troels Gravesen's Discovery 861 DIY loudspeakers which are awesome) and some upgrades which have been made (Jantzen Audio Silver-Z caps and Sparkos Labs SS3602 Dual Opamp). It has been used for ~1,5 years as a headphone amp and I was very happy to listen to it (all stock components, AD823ANZ opamp). But as a preamp it was also very good, best I have ever heard. Plenty of details, pleasant to listen. Upgrading C1 and C5 to Jantzen Audio Silver-Z provided some additional clarity on highs, but SS3602 pushed it to another level. Everything has improved: much more precision on lows, bass guitar sounds much more clear, separated; punchier drums; vocals much more separated, articulated and pleasant; highs were good before, but with SS3602 become even more airy, so precise. Lower distortion gives an ability to listen louder with no fatigue. I expected some improvement, but SS3602 provided much more than I thought. Obviously, your experience may vary due to the different speakers, amp. But still, I highly recommend to try SS3602! Keep in mind that you'll have to provide some space by drawing back C3, C4, C9.

I don't think that Silver-Z caps alone give a big difference compared to 5$ foil caps, but 40$ for 2 is not as much. Also worth trying.