After building one, decided to build another, to operate them in balanced mono. And build my own case with heatsinks that have been kept in my garage for 20+ years.
This was a fun one to build. I used a fan to cool off some smaller heatsinks. Loving the sound so far!
I built a pair of the 1.8 version amps over the past year, along with an ACP+ preamp. I have previously built a few 500 series modules for music recording so I suppose I qualify as an intermediate builder. The only issue I encountered with the ACAs was a broken brass stand-off for one of the heat sinks from over tightening. I drilled it out and was able to friction fit a replacement without too much trouble. Everything worked perfectly after powering up. Drilling and wiring the ACP+ chassis was by far the most difficult part of the whole project, I’m using this set-up (bridged mono) with a Rasberry Pi music streamer and am so happy with the results that I will be replacing my tube integrated amplifier with the Amp Camp gear. With sensitive speakers (Zu Omen DW), this set-up is awesome for a home system and provides the extra satisfaction of DIY.
Completed this build a few weeks ago. Took me several days to finish but was my first attempt at assembling a kit and I didn’t want to rush things. Instructions were pretty straightforward and I had my brother to consult if I was unsure of any step (he’s been building ham radio, stereo, and guitar amp kits for years). Pleasantly surprised when it fired right up. And the sound? Despite having read many positive reviews I am completely wowed. Running it with Zu Omen DW speakers in a fairly large room and at moderate volumes it sounds fantastic. Doesn’t deliver the bass of my Cambridge Edge A integrated but is impressively resolving and detailed wit excellent sound stage. Amazing little amp. And DIY store service was top notch. Thanks!
I had a lot of fun putting this together. The instructions were straightforward and it worked first time!
The build experience was tons of fun. All components that came with the kit were well within spec. After listening to Mr. Pass talk about his stash of parts, I feel like a got few gems. Populating the PCBs and wiring the amps up was a great couple of afternoons (I built a pair). Build instructions are perfectly clear.
As far as what they sound like:
They are crystal clear and massively transparent. They will simply recreate the source material they are provided.
I run them as a set of unbalanced monoblocks in a relatively nearfield environment and enjoy them almost every day.
I’ve built several tube amps, but haven’t had success with any solid state builds until I took this kit on.
And what an amp! I listen to it every day with bookshelf speakers. It sounds beautiful. Like my favorite tube amps, this amp demonstrates how much can be done with a simple minimal design.
Nice quality of components.
During the build without chassis, it took me some time to measure and figure out the hole-pattern for the PCB on the heatsinks. I couldn’t find any values for it in the guide or forum.
Now i can proudly say i have built my own stereo power amp! And i have learnt some new things.
My feet are wet and the water was indeed fine. Dare I go deeper?
Thank you, both creator Pass and supplier DIYAudiostore.
Sound is big on my 95db sensitive speakers.nice sounstage.cool sounding.
No complaints.
As bridged monoblocks they have the best sound ive heard to date in my system. instrument detail , stereo image in vinyl has exeeded all my expectations and the overall sound is beautifull, gives you a smile. Totaly recomend it and will buy again to build for friends
First and foremost, this is a nice little project! That being said there were a couple of small issues I ran into. First, two of the resistors were the incorrect size. I dug out some correct ones from my stash, not a big deal. Secondly, the instructions were sometimes difficult to follow. For example making the back panel power bus, I soldered it to all three terminals before reading "do not solder to speaker terminals yet". Maybe I was in a hurry, but I had to unsolder and redo that bus like 6 times. Read all the way through each section before soldering anything. I also had to redo the enclosure to heatsink mounting a few times to make sure everything fit without touching. It's entirely possible that my excitement got the best of me, and I got ahead of myself (normal occurrence). After all is said and done, this is a fun little amp. It definitely does not have the power reserves that my Yamaha M-80 has, but it can drive my Cornscala's (6 ohms) to reasonable levels, and sounds pretty good doing it! I will soon be trying the mono mode, when a friend brings his ACA over for a listening session. I have high hopes for that as well. I would definitely build another one, given the chance.
Recommended. It went by quick. I'm burning the amp in to the Grateful Dead as I write. Very surprised and pleased the sound quality, loudness, and bass. Build hints: 1) Read 1.6 (board build) and separate 1.8 (wiring only) instructions end-to-end first including helpful comments. 2) Brush up on soldering technique 3) Would be nice to get a chart listing wire count and length but plenty wire supplied. It worked first time. Easy peasy.
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!
I bought this as a fun holiday project, and with appropriate reverence for the talents of Mr Pass, but with none for myself as I'd never soldered before. I kitted-up with a basic soldering iron and a decent multimeter and took a deep breath. Rest-assured, if you're a reasonably methodical person capable of following basic instructions, you'll be fine. Faults were easy to track down using the diagnostics supplied and first principles. Mistakes were easily remedied. Once I'd biased the channels (simple but finicky process) and checked for DC offset (almost negligible at about 3mV), I hooked the amp up to my usual Sugden IA4 running as a preamp. This being a low power amp, I was happy to be feeding it to very sensitive Klipsch Forte IIIs. I expected it to sound decent. It's way better than that, it blew me away. While it lacked the muscularity of a higher-powered amp, it had no problem driving the speakers to ear-splitting levels with real class. The midrange clarity and soundstage are lovely, really suiting quieter acoustic music. The biggest issue I noticed, is that during particularly busy sections, the amp couldn't deliver the clean and tight bass that the Sugden can - the ACA bottom-end reaches plenty-deep, but its presentation is more disorganised and smeared. Another thing to note: this amp runs hot. Very hot. It has that classic slightly warm class-A sound and the heat that comes with it. This is probably not an amp to leave on all the time.
So, is the Amp Camp Amp any good? Well, there is joy and pride to be found in building the amp yourself, but that only goes so far if it sounds bad or even just disapoointingly fine. Fear not, it's much better than that. I'm so impressed that I'm building a new desktop system around it for my workspace. I've selected Omega speakers for their ease with flea-watts... and I see those Zen Triode kits... However, ACA? I freaking love it!
I build 2 mono amplifiers together with an Korg NuTube preamp. Ordering was easy, delivery fast and packaging top notch. The build was easy en complete fun. They drive a pair of B&W 607SE with ease in my small room and i am very happy with them also thnx to Steve Guttenberg he made me purchase these items except the preamp but it is a wonderfull combination.
I started this project being amazed by all the comments and fantastic feedback posted everywhere. I thought this is definitely something, well, I am a natural maker with very little electronics knowledge and an audiophile newby, so it could be an inexpensive way to begin this journey and it catches me deeply.
The sound signature is delicious, the only drawback is its small power, but found out thanks to James from TungstenAudio and his genius and generosity, that it is possible to hack the ACA and take it to a better level, I followed up his recommendations and wow, more power and even better sound, it reminds me the sound stage of a tube amp, very, very nice.
You can find the suggested upgrade here https://www.diyaudio.com/community/threads/aca-amp-with-premium-parts.328357/post-5569767
I am running a pair of Elac's Debut 6.2 (87 dB sensitivity) and they sound great.
My next step is to try a 48V linear power supply and see how it performs, if it does't give more power I will purchase another one to build a mono block set.
Thank you to Nelson Pass for his creativity and generosity and to DIY audio to make it so easy and also thanks to James from Tungsten audio for the tweeks, he really took this mini amp to another level.
I finally purchased this DIY, my first one to build as a complete kit. I up the stakes by replacing all the caps with AudioNote (blackgate version) Caps and Mundorf for the coupling cap. i also used silver solder and silver wire for all. All I can say it is all the hype I've read. I paired it Klipsh Rp600M and sometimes switch it to my Maggie LRS just to listen how it sounds
well, compared to my reference system, it is holding up its claim to fame. i am amazed that this simple design, using upgrade caps and driven by a Tube amp, can sound that good. i suggest use better caps as you can
The build was not very difficult. Just follow instructions and you wil get there.
I build two ACA's to serve as dual mono block. The sound is magnificent.
I use it with and AUDIOPHONICS EVO-SABRE diy DAC, without an additional pre-amplifier. That still gives plenty of volume to listen.
