COMPARISON TEST: Nelson Pass Amp Camp Amp (kit), Schiit Aegir, First Watt J2 and...

[@freiheit6398]

Nelson Pass is awesome for supporting the DIY community. A firstwatt + klipsch cornwall is my dream system. Keep the videos coming! Thank you, Steve.

[@steveluck9541]

Big shout out to the DIY Audiostore boys for the care taken to gather all the parts and cut the different coloured wires to a generous length. Thanks for sourcing a good quality power supply. Thanks for the great photos and easy build instructions. Thanks to Modushop for the high quality case machined painted and printed beautifully so that it all goes together with no problems and looks great when finished. The postage getting the parts to your house would cost more than some people are claiming they could build one for. Cobblers to that.

[@richarddortch6122]

Thank You! It takes quite a bit of work to plan and put these kits together. I'm glad to see you like what we do. We are just a small group of enthusiasts that believe in the value that exists in DIY.

[@jeffkalina7727]

The only thing that beats DIY is buying them already assembled by a competent party as I did last November. Two Pass ACA mono blocks for $350 + $140 in upgrades to a better 24V wall warts and improved resistors. Sold my Cary 120S MK2 amp. The little guys brought out hidden detail and a clarity that made me say "More". Purchased a 9 month old XA25 for $3k. Now I am in heaven! Kept the little guys too.

[@DaveSchulze]

Where did you find the guy to assemble and upgrade?

[@jeffkalina7727]

@@DaveSchulze They were built when I purchased them.

[@DaveSchulze]

@@jeffkalina7727 Assuming then you didn’t by from the Amp Camp site? I didn’t see that option.

[@ericwilliams2173]

Thanks, Steve, for the comparisons. I built my own system with two Camp Amps in bridging mono mode driving a pair of KEF LS50's. I went to bridging mostly because a single stereo amp just didn't have the gain to drive the speakers to the levels I needed, especially with some lower level sound sources. The speakers (and their amps) sit on pedestals essentially in the middle of the room, about 8ft from the listener, and the accuracy and imaging is amazing, certainly the best sounding setup I've ever put together. (Which is why hearing your comparisons was nice.) The amps are driven by a Elekit TU-8500DX tube preamp (also a kit), and I later added a Klipsch R-112SW powered sub-woofer to fill in the low end, which adds a lot of fun to the listening experience.

[@nacarp2000]

Steve, the ACA have 3 modes. The two that you tested, the Stereo mode with RCA with the high level of 2nd harmonic and the Balanced Mono mode where the 2nd harmonic is cancelled out. The 3 option is the Parallel Mono on RCA, where the channels are added together in phase, that way the 2nd harmonic is not cancelled it. It should just be like the Stereo mode but with more Watts. I'm thinking since you said you might just keep one of them (for the harmonics I guess), that maybe you want to try them this way and see what you think. I'm sure other people other than myself will be interested in your observations too. I am currently in the process of building a pair too. Thanks.

[@BicycleJoeTomasello]

did you build the Mono pair? I'd like to hear your thoughts?

[@jessemalsbury9008]

Thanks for sharing this. I'll give it a try as well. I Initially bought a pair of them to run in dual balanced mono.

[@scottyo64]

I love the fact that you agree it's what each person likes. People have such different tastes. When I go to my step daughters and her and her daughters are jamming out to an Alexa Dot, I almost get jealous. They have fun dancing and singing along. I can't fault them but I can't do that myself.

[@stephensmith3111]

Kind of like the old days of listening to 45 r.p.m. singles on a portable record player with a piezo-crystal 'cartridge', cheap transistor radio class electronics (or basic tube circuit if you're even older) and a single paper cone speaker (maybe with a whizzer). Think of the scene from The Blues Brothers when Jake and Elwood were back in the basement of the orphanage listening to blues records with their mentor Curtis.

[@christianjforbes]

2023 … I still run two ACA amps, love them as much now as ever.

[@awdadwadwad1723]

I have First Watt J2 (got it second time already) and Pass INT 25 and I had INT 30 and in my option Nelson amps are one of the most pleasant sounding on the planet. I had top A class from Accuphase, Luxman, also AB Yamahas, Cambridge plus much more. Nothing comes close to musicality and pleasurement of listening of Pass amplifiers. So I'm pretty sure those 300 dollars mono puppies are a real steal!! PS. they all running HOT ;)

[@juliaset751]

I am using 120 mm computer case fans sitting on my shelf blowing on the heat sinks of my J2. Fans are DC so you can choose a wall wart with the voltage you want for the speed, I’m using 8V. Heat sinks are now warm not hot. They are silent.

[@mitchsefton9402]

Just love your enthusiasm, your never ending optimism and of course knowledge. " i love my job " sums it up perfectly.

[@OldTooly]

I enjoyed this review. I am 2 years(of about 57 years in audio) into experimenting with near field low power sound. I have been running massively powered AND efficient speakers for decades so this was quite a switch and your statement about the sound field, detail and disappearing speakers was so spot on. Listening to a pair of 20 year old Celestion Model A compacts, being driven by a Wavebourn Edelweiss 3 amp (KT77 tubes 6wpc) directly off a PSAudio DAC created the most perfect sound I had yet to hear in my life. I was up late into the night for months every night playing every kind of music as well as rediscovering my classical and jazz roots. This is also a great system to check audio components since every detail is revealed, short of thundering bass and massive dynamics. It was nice to see something I had stumbled upon myself had also been experienced by a seasoned expert.

[@Canadian_Eh_I]

Good for you! I've found the benefits of high efficiency to be enormous. It turns out that you can get much higher quality watts for your dollar when you go low power. The problems start when you need more than 100watts for your speakers. I currently use a pair of Earl Geddes Abbey's which are 95db speakers and the imaging and directivity is phenominal and all they need is a few watts !

[@mmdusa]

I both sing your praises and curse you Steve. You are one of the main reasons I went with a Pass Labs amp when I decided to step up to the big leagues. I absolutely LOVE it. I can't believe how good it sounds. Yes, there may be better amps out there. I'm sure there are. But I have truly loved this amp. Now, I'm getting ready to buy a Pass Labs preamp. Again, partly because of you. You are costing me a lot of money. But I also have to thank you for introducing me to the wonder and genius of Nelson Pass and Wayne Colburn. For the quality and build, they are kind of a bargain. Don't tell them. I don't make much money. But I know I won't regret selling that kidney to get my preamp. ; - )

[@pukebjorn]

I just want to say thank you so much for this review. I already owned an amp camp amp, but after viewing this video, I built another one. Wow! The difference when running them as mono blocks. I was stunned and you were absolutely right in your review. I am using a Musical Fidelity X.Can 8 as a pre-amp which produces enough gain to drive them (almost too much), coupled directly to a Moon Dac. The Amp Camps drive my Dali Helicon 800 without any problems. Only trouble is that I may have to build a B1 buffer too....:-)

[@pnojazz]

Steve, thank you for doing a review on these amplifiers! I recently purchased a pair already built from a previous owner. Unfortunately my small watt horn speakers are long gone to a new home. All I currently have are Martin Logan Electrostats (Spires) that have a sensitivity rating of 91 dB. I’m not a loud listener by any means. So, when the amps arrived I wasn’t expecting much. Connected in xlr bridge mode, I said to myself, here goes nothing. The amp’s truly began to open, and heat up after an hour. Having owned Pass Aleph series amps, the 3,5,O’s, some 25 years ago, these amps were almost a trip down memory lane. They were pleasurable to listen to. I was floored they drove ML’s to the levels I needed without a hint of fatigue or strain. Thank you for another honest and accurate review!

[@lynnpoole7830]

Steve, thank you so much for the review of the ACA! I love mine. I am super impressed that they compared as well as they did with the other amps. Hey, Steve likes my amp, how cool is that? LOL

[@Leicaphile27]

Settled in with my morning cup of coffee and another great episode...

[@carlitomelon4610]

Fun while my system warms up and the Tetley British blend tea brews;-) Now for an hour of baroque to start my day...

[@cablebrain9691]

Haha.....exactly what I had done. 😋

[@steenhansen8]

Have an older Aleph 3 and will never let it go. Pass makes great amps.

[@rickg8015]

Recap those. Lytics break down in time especially at Class A. Ask Pass about an input board mod. Get an experienced tech for the job..

[@steenhansen8]

Rick G :Thanks Rick, didn’t know a mod existed

[@rw3915]

The Aleph amps are not tolerant of average or even good preamps. I went from an Aleph 5 to the Aleph 0 to finally the Aleph 1.2s which belt out 200w/channel into 8 ohms. I used an Adcom, Sonic Frontiers 2 box set up, with a myriad of tubes from Upscale Audio, and then the magic really happened with a Pass Preamp X02, the 3 box set up. Ohhhhh man!, The magic really happened with the 1.2s and X02 preamp. Those made my Von Schweikert VR6s sing like nothing else I’ve ever heard. Just glorious and an ethereal experience. So Aleph 3/5/0/1.2s yes, but using a really good preamp really takes the game from semi pro, to pro. Anyways...

[@steenhansen8]

My words exactly. My “3” is fed by an Aleph L. Pure magic.

[@stillmotion7779]

I'm not into DIY audio but my 10 year old girl asked if we could do one together, Here I'm placing my order 🤦‍♂️let see if we could make it work.

[@rklmbd2934]

How did it go?

[@IcECreAm-sv2qv]

did you ever get it done?

[@939Productions]

Good on you for getting her into hifi audio. She will never have time or money for boys and drugs.

[@PanAmStyle]

Two things: 1- I am tempted ... my first amplifier was a Dynakit SCA-80Q, which is a really nice amp if done correctly. In fact, I’m running an SCA-80Q (factory built) for my back porch system and combined with the Dayton B652-Air speakers for the fronts, it’s really wonderful. In fact, I’m considering getting some of the upgrade kits for the Dyna. So building another kit amp 50 some years later? Oh yeah, that would be fun! 2 - All hail Steve Deckert! All hail the Zen amp! I have been tube rolling mine, including rectifiers(!), and it is SO SO sweet! It drives Large Advents - admittedly in a small room, but even in a larger room it would be very satisfying. As Steve (Deckert) says - if the first watt sucks, why continue?

[@nathanas64]

I was on the fence whether to build the Amp Camp but Steve certainly motivated me to do so and I ordered the kit!

[@lextr3110]

so do you like it, i ordered two for a 3 way crossover (mid-high)

[@nathanas64]

@@lextr3110 definitely like it. I paired mine with a Fosi tube preamp and with Klipsch RP600m speakers. It actually sounds pretty good. I also think you will enjoy building it

[@qqube4762]

I built a pair of Nelson Pass son of zen amps at 5 watts from the ground up. That allowed me much flexibility. Still have these amps after 20 years. This is my go-to amp when listening to headphones. Old and new headphones including stax headphones.Thanks for the video. Videos like this gives me new ideals

[@bombslab]

LCD 3, HE 1000 V2s and Susvaras - Oh my! Also, I've been waiting to pull the trigger on a pair of ACAs...I'm an EE student and Nelson's interviews are how I found this channel in the first place. Awesome channel BTW!

[@davidatrakchi2707]

Hi Steve, your review made me check my Nelson pass ACA as mono powering one speaker only. I liked the results so I ordered the second amp and I’m really amazed by the results I’m using 90dB per w Bronze 2 by Monitor Audio speakers and I’m very pleased getting such nice sound at a very modest investment Thanks

[@tomd5678]

Just finished building mine today. In my system the treble is sweat and lively. The midrange is musical. The base is very strong but a little muddy- that's probably my room. It's plenty loud. It gets quite warm/hot. I found it easy to build and the online instructions are good. Take your time. Get the right equipment. Organise your workspace. Watch a "how to solder" video

[@rjpwp001]

I now have a fully Audiophiliac approved system. I just started running a stereo ACA with my Zu Omen DWs and I’ve been staying up way too late listening to a bunch of favorite recordings. The sound is rich and smooth but with crisp highs. Listening to the snap of drums in good jazz recordings is almost shocking in its realism. And vocals. Wow. I put on PJ Harvey’s To Bring You My Love album and it’s like she’s in the room. It plays pretty friggin loud with 97db speakers. My Outlaw 2160 may be sitting idle for a while.

[@lynnpoole7830]

I like Polly Jean too.

[@vivianvaldi7871]

Seems great but what source format ? CD's ? If u can appreciate CD's with them, then what about DSD's ! You should call the doctor before the uppercut in the face.

[@rjpwp001]

Update. I’m now running two ACA’s in stereo monoblock via XLR. The improvement is tremendous. The sound is smooth yet very detailed and punchy at the same time. Source is Amazon HD. I’m using an SME ADI-2 as my DAC/preamp. I’ve never heard an actual First Watt amp. I’d love to hear how the monoblock ACA compares to the “real” thing.

[@DaveSchulze]

I just got some Omen DW Mk2 and I'm dying to build two ACA to listen!

[@rjpwp001]

@@DaveSchulze I will say this. I loved the sound of the ACA monoblocks with my DWs but after swapping them out for something a bit more powerful, an Iotavx PA3, it was clear they were not doing the DWs justice. The Iota had so much more control over the speakers and took music to places the ACAs could not go. This was unsurprisingly apparent at louder listening levels. I have since pulled the trigger on a used Pass INT25 to get back to that Pass sound. It did a number on my bank account but I’ll be keeping this one for a long time.

[@yannick930]

With a linear power supply and a bigger power supply this amp will be a beast.

[@sparkplugspark5987]

Thanks Steve, your best review yet, im buying a mono pair ACA on foot of this review, gonna pair them with the Klipsch RP600

[@user-od9iz9cv1w]

Great review. Really brought these amps to life by comparing to the other noteworthy amps. I am a DIY enthusiast. You briefly mentioned the upgrade forums. The ability to search for ideas to upgrade and then trying different components really makes a DIY project special. Not only does the sound improve, but that pride of ownership. I think the amp camp kit is an amazing value.

[@nospoon17]

Love you Steve ! I couldn’t “pass” this up either. I never really pictured myself doing DIY audio amp builds but here I am with the pass kit in front of me. Here we go…wish me luck

[@jessemalsbury9008]

Yep - I bought 2 as a result of this review - dual mono hooked to K Horns. Can't wait!

[@murraywebster1228]

A Gentleman and a scholar, always a pleasure to watch.

[@luctardif8444]

Wow, great review of different price tag amplifier. Steve you’re one of the best!

[@sirDanBaker]

‘A warm hug’ hahaha exactly how I would describe my ACA. Brilliant little amp, had good fun building it and listening to it. It does run really hot indeed, it uses about 120 watts (230v) to produce the 2*6 watt. My Bryston 4B Cubed does outplay it in all aspects though but it is approximately 24 times as expensive. I’d go for a larger actual Pass amp if not for the immense amounts of heat and energy usage, they’re just not practical for everyday use with a touch of HT use in the mix.

[@logotrikes]

I love the flea-watt amps. Just built a couple of spud amps based on a Fred Nachbauer design on a dissimilar pre and power triode tv tube. One watt from one tube, with zero NFB... The only extravagance was custom wound output transformers. I used Hammond for the power transformers, 2 per side. A lot of money for 1 watt per channel but I saw it as a learning curve first attempt at a tube amp. It sounds nice enough to me but of course there's a lot of confirmation bias. I enjoyed the build as much as listening to them, and that was the real purpose, to enjoy and learn from the build itself. Always fancied the Decware amp. Maybe that'll be next, or an Amp Camp...

[@bnkk1]

I bought a kit with the intention of building it with my Daughter and introduce her to HiFi. Life happened and we were not able to get together as planned last year so I built it. Wow I fell in love. I bought a second kit to build with her. I couldn’t wait so I built it. Running the pair in mono really got my attention. I ran the pair with a DIY Pass B1 zero gain preamp. Wow! Now my Daughter now has the pair. She loves them, and I need to build another PASS DIY amp(s). Maybe an F6?

[@rbhis000]

I highly recommend the F6.

[@stimpy1226]

So I know now that I'm not crazy after hearing your review Steve. Well maybe I am crazy but after I completed the construction of the amp camp amp I was floored by the sound I heard coming out of the Klipsch RM- 600 P speakers that I purchased for voicing. I never expected to hear the quality of sound that this amplifier is capable of. Now I'm thinking of building another kit to send to my son who has the first unit if he agrees to buy the Tekton's.

[@sparkplugspark5987]

mono or stereo with the rp600s?

[@stimpy1226]

Sparkplug spark. Stereo. That's why I'm thinking of building a second

[@sparkplugspark5987]

@@stimpy1226 was worried the ACA wouldnt be enough power for the 88db RP600s, so you find them a good match?

[@thomasmleahy6218]

I think Danny Richie @ gr research has a mod for the rm600p.

[@stimpy1226]

@@thomasmleahy6218 I built the PASS kits and purchased the speakers for voicing. I sent everything to my son in California when I was satisfied that the amp and preamp sounded fine so I’m not doing any modifications since I don’t have the speakers anymore and my son is happy. It’s difficult to enjoy the small Klipsch speakers made in China when I own a high-end system with Magnaplanar 3.6R’s.

[@merrillaldrich9170]

You couldn't PASS up this opportunity - I see what you did there, Steve

[@kozmiczian]

great work, Steve. I have set up quite a good 'nearfield' system, using my Android phone as source and streaming Qobuz. Audioquest interconnected to an Emotiva Basx-100 amp . . . driving two 80watt powered subs, connected to a pair of Klipsch B-200s on sand-filled stands. Small room 9x12. Thanks for the nearfield confidence booster. I was hearing a 24x192 recording, other nite, blew me away.

[@jlmain5777]

Great review. I’m digging out my soldering iron, work light, and visor.

[@gustercc]

I would like to undertake a project like this, but I’m afraid I’ll electrocuted myself. Ha ha

[@FOH3663]

@@gustercc The beauty of this kit is it's all low voltage. The power supply is already built, you simply plug it in to the rear of the amp chassis.

[@gustercc]

@@FOH3663 thanks for the info!

[@Larstig81]

I finished the amp camp amp yesterday and playing with it right now. I connected it with the Cambridge Audio CXA81, my main amp, it sounds really good. Don't know which better, but the soundstage is maybe better. I need more time, because I use temporary Audioengine P4 speakers and waiting the ProAc Tablette 10 Signature to arrive.

[@homeaudio-ny7cv]

It's really a good episode and I was tempted to browse the webpage for placing order. Just about the final click, I started to see more detail circuitry on this amp kit...then I dropped. It's really a good kit but in old term, it called "OTL" amp circuitry, i.e. with a series connected capacitor for blocking DC to output (the speaker). I could understand that it is much easier for building a kit with single end power supply (i.e. 24V and GND) especially for beginner. The circuit design is very good indeed anyway with MOSFET and simple biasing, more direct and less electronics. The chassis design and high quality jack, binding post...it's really a piece of art after finished.

[@MrSouzy]

I actually use a hood 1969 class amp which I soldered together myself. That has 15 Watts and actually has enough power to drive a set of kef LS80s (whereby I normally use a set of quad 12l2s which are more sensitive). It's hard to describe the sound but it is very transparent and has a weightly low end. Designwise it is very simple. Subjectively it puts out about the same power as my NAD integrated. But boy does it run hot.

[@morespinach9832]

Cool video and insightful as always. Schitt Aegir is a gorgeous sounding thing.

[@williamsharp5973]

One of your best and most informative episodes ever. :)

[@AlanFenick]

I remember a demonstration back in the early 1970’s of the Klipsch Cornwalls being driven by a six transistor pocket radio to prove their efficiency!

[@carlosroig5315]

This is a great review and comparison, thank you Steve!

[@carlosbauza1139]

Dynakits and Hafler kits were glorious!

[@stimpy1226]

I built the Hafler pre amp. David Hafler was another design genius. A leader in the audio industry.

[@BrianNavalinsky]

My first DIY, 1972 in my dorm room, Dynaco SCA 35. Thanks to Paul Wilde, my project ee, wherever you are.

[@OrganNLou]

Steve, you inspired me to get into the low power, class a amp designs. I ended up with the pass F5 clone, and have been in heaven.

[@Carl-bd1rf]

One of your best reviews if not your best Steve!

[@mrboat580]

I have 2nd version of the Amp Camp made into 8 watt mono blocks much like the original prototypes. I am powering a pair of diysoundgroup Fusion-12 speakers with them and it is a wonderful thing. Half power will run you out of the house with sensitive speakers. I listen near field at around 87db as my sweet spot so this amp kit is more than adequate. The kits were out of stock but the boards were available so I basically sourced the BOM separately myself. I have since bought the latest, stereo version when it became available, just because I was so satisfied with the sound, and the crude simplicity of the circuit. This tells us perhaps, how much, too much, we spend for audio.

[@joeycastillo1496]

Thanks Steve, I was very interested in this review!!

[@jessemalsbury9008]

Thanks for the review - I bought 2 ACA kits as a result of it.

[@signalpath9597]

Great video as usual, Steve. Stupid question but you mention the ACA has switching capability. But you would still require 2 for bridged mono, correct? Also, do these amps require a seperate preamp? Thanks in advance to anyone who answers.

[@stephencosta6814]

Yes it does

[@williamwest9253]

The question is how does the ACA monoblocks compare to Schiit Aegir monoblocks. I love all these amps for different reasons.

[@nabdrumworks4719]

Great review and detailed feedback, I thank you for your appreciation of music and electronics!

[@HareDeLune]

Steve: "How good can a kit amp sound?" Me: "Let's find out!" Excellent review, Steve! Much appreciated information. Thank you very much!

[@michelcouture7026]

I just finish the build of the ACA, Still have to do the first test and gain adjustment. Looking foreward to put it to the test with DW6.

[@davidatrakchi2707]

Hi, I used the present situation of lockup’s to get me a ACA kit, built it bringing to life my old skills from end 60׳s when in Israel kits were the only option for music fan youngsters because only the wealthy ones could afford a real amp. This hot little thing feeds a pair of 90dBA per watt @1m Monitor Audio Bronze2 and this setup simply positioned me at a new, much higher degree of fine music. But the journey through the rabbit hole only begins , next step is to follow your advise and play it as mono, and if I will like the sound go and order the second hot thing which will playas double monos And than, what׳s next in the journey? Thanks , best regards and stay safe David

[@stevebrown9363]

Wouldn't you know, the kit is sold out, but looks like more coming. I actually built one of these a few months ago, and I'm frustrated that there is now a new version (1.8 I think), because I'm guessing that precludes me using them as two mono amps, but I'll check. For years I've run tube amps and my last build was a PP KT88 mono block build, which I love, but the ACA holds it's own in my small listening room with 97db efficient speakers. Steve mention how hot it gets, in my experience I would not say hot, but very warm? Yes. Of course compared to a pair of KT88's... The kit is fun, but components are tight on the board, I'd highly recommend an appropriate tool to hold the PC board while you solder and a rather fine tip on your iron.

[@darrenshepard5812]

Here is a forum post describing the difference between 1.6 and 1.8. www.diyaudio.com/forums/the-diyaudio-store/256660-amp-camp-amp-kit-1-6-1-8-a-69.html#post6262559

[@Diatonic5th]

Excellent review! Your enthusiasm always makes it a pleasure to watch your videos.

[@hugobloemers4425]

This is what I have been thinking about making good audio cheaper (apart from buying Shiit). Sell kits that people can either buy and build or tap in to a community of audio and electronics hobbyists who can compete to build it. More over the better your reviews the more you can ask. And everybody can benefit so in that case the Aca camp becomes accessible to people who want plug and play and some hobbyist can have fun and earn a bit on the side. One could call it UberAudio.

[@brianhansen7274]

I hope that you consider doing reviews of DIY audio. I have always been intrigued with them. Speakers and Amps both.

[@riccitone]

I would love a big hug from theses amps. Especially such an affordable hug. May need to save some shekels.

[@seanlobdell502]

I wish you ran a pair of the Aegirs in mono mode. That is what I am running now and the sound is better than in stereo IMO.

[@pemmicanstash394]

I’m running a pair of Aegirs in mono, too, and I’m pretty satisfied with the sound; it’s a big step up from running one in stereo. However, my Elekit 8600 (another DIY) is significantly better with holographic soundstage and sweet midrange.

[@epi2045]

SG the OG of audiophiles! Great video. I’m fine with 8 wpc BUT it seems small for Class A. Will it last?

[@yourchildrensghost9736]

This was Awesome, Thank you Steve. It is Appreciated.

[@artsabound7627]

Thanks Steve , fun , informative and descriptive .

[@superdougie10]

"Roll Your Own - kinda sound" gotta love that expression Steve....funny.

[@lloll69]

Fun huh the Aca camp. It's good fun for a tube amp lovers.my friends who owns expensive tube amp is both suprised and a little upset a simple cheap design can do so much .

[@hubreyireeuw6507]

Steve, I always like your podcast about audio. You have the gift of telling a story. Love it, keep going.

[@alfagerup]

Thanks a LOT for this good and entertaining informations Steve !! 👍 🤗

[@mdr4670]

Great comparison review Steve! I'm saving up for the Pass Labs Int 60 and Cornwall 4.

[@bobkrueger194]

Steve, what are your thoughts of the Aegir compared to Cambridge 851XD? The Cambridge unit looks really interesting and uses some good sound build principles.

[@CobraChamp]

Nice review. I’ve been wondering about the ACA for some time....

[@patrickmcguigan5939]

I've been tempted to add a pair of power amps to my system for a while..... Now I'm REALLY tempted!

[@20thcenturyboy85]

LOVE your content, Steve! Thanks for all your videos.

[@nunyabiz2016]

Glad you said that about the distortion. The guys over at audiosciencereview got a hold of this and went on and on about what a charlatan Nelson Pass was for having his name on this amp XD and I'm sure most of them didn't listen to it at all.

[@eetu2532]

Yeah, one has to look at it from both sides. As Steve said objectively looking the ACA does poorly. High distortion (yes mainly H2, H3 but also H5 when pushed a little), very low damping factor, low efficiency, low power that limits speaker pairing. ASR awards engineering prowess and measurable performance. This is a fundamentally different approach to that of Steve's (and many other audiophiles). It's a question every listener has to answer: do I want my system to be as hifi/true-to-the-source as possible or do I want it to sound as good/pleasing as possible. There are recordings out there that are supposed to sound cool and clean and not like a 'warm hug'. I've also read that the parts cost only $14, that may also be the reason for some critique towards Pass.

[@editorjuno]

@@eetu2532 -- It doesn't sound good either, at least not by high fidelity -- "great faithfulness" -- standards. It's a "stunt" product IMO.

[@Diatonic5th]

Typical ASR cultists. They spend more time measuring gear than listening to music.

[@editorjuno]

@@Diatonic5th -- The silly gadget flunked the listening test too. I've been listening to audio gear for 50+ years and this latest low-power, low-feedback, Class A craze is just that -- a passing trend among self-styled "audiophiles" with zero audible benefit. Nelson Pass has found himself a cozy market niche with these things -- he knows danged well that stuff isn't high fidelity, but rather the audiophile equivalent of a fashion statement. With nearly 10% THD+N at anything near rated power, you might as well be using a pair of old Fender Champ guitar amps instead. To quote Amir's subjective impression: "Is this thing on? That is the expression that immediately came to mind after I hooked up the ACA amp to my Sonus Faber Concertino bookshelf speaker. Granted, the Concertino is spec'ed at 86 dB efficiency but come on, I could barely hear it. There was no bass naturally. But not much above that either. And this was with my Topping DX3 Pro at full volume." "For grins, I plugged the US $74 tiny little SMSL SA100 Amplifier which I recently reviewed into the setup. Now the speakers came alive, with lots of bass, great dynamic range, and detail. Yes, the amp started to cry when I turned it up much but until that point, it left the ACA so far in the dust it was not even funny."

[@richarddortch6122]

Yep! I don't want to listen to a piece of medical equipment......

[@williampearson4968]

Steve, your enthusiasm and passion for value in Hi-Fi is infectious! What a value --- Turn back the clock 50 years to 1970 and the cost is only $47 per the U.S. CPI (Consumer Price Index). How would your First Watt Sit-3 instead of the J2 compare with ACA Kit? They are of the same Nelson Pass design pedigree.

[@leekumiega9268]

Back then they had the Dynakit 70 , a 35 watt per channel stereo tube amp kit designed by David Hafler , it sold for $99.95 .They were so popular (nearly a half million sold) that you can still find any part you need on line to keep it going.

[@morris7025]

If you Love Hi-Fi Music i highly recommend giving DIY a try! Learn from the Master, Nelson Pass! Build amazing gear that sounds great. Do it!!! : ) I will say the big difference between the Amp Camp and First Watt amps is the Power Supply. Having a well made, robust PSU on hand for your amp really makes a difference. But for the money! Wow, DIY : )

[@westcoastbruin9285]

Hi Steve. Great video. Are you going to try using 2 Aegir amps in mono configuration at some point to see what they sound like? Also, does the Aegir amp sound different than the Vidar? Thanks!

[@jamesmachado9366]

Amp camp monoblocks with Merlin VSM speakers. They rock!

[@dansav4519]

This is just the video I've Been asking for thankyou Steve!

[@patkoss1945]

Just a follow-up. I have two running as balanced monoblocks paired with Zu Audio Dirty Weekend Omens in my office. Loving it with ALL types of music.

[@DaveSchulze]

I just got my Zu Omen DW and I'm looking to run Aegir or dual Amp Camp. Sounds like you found a winner. What is your preamp?

[@patkoss1945]

@@DaveSchulze Yes this is a winner. I run dual Amp Camp still after 1 year. The pre is a ProJect Pre Box RS Stereo.

[@ChaiBearProductions]

A pair of these in mono drive my 91db Chora 826 towers to ear splitting levels while maintaining composure. As I push my DACS volume they just come alive with these amps.

[@beckhaver]

Did you try the amp on the Magenpan LRS? I know that speaker chews up amps, but I would be curious to see the results none the less. Thank you for the review Steve!

[@ufarkingicehole]

Lol... almost GURENTEE that this would be a terrible match.

[@TwangThang57]

Forgive me if I missed this, but what preamp were you using in front of the ACAs?

[@SteveGuttenbergAudiophiliac]

Pass XP30

[@gorkushka]

Thank you for covering these 8W and 20W Class A amplifiers. I was wondering if you could do an episode precisely on speaker choices for low power amplifier power apartment dwellers like me - many of us have 300B and 2A3 Bottlehead kits, and more. What speakers are out there that are efficient enough to be enjoyable with 8W Power (300B/Amp Camp) and further what about speakers that pair well with 2W Power (2A3 Bottlehead, Decware Zen and others) ?

[@marc.0000]

Hi Steve, I am following your videos for a long time and I enjoy a lot with your comments…. II would like to know your opinion about if my two mono ACA PASS amps could work enough well with the KEF L50 META or it would be too much for my ACÁ PASS. Thanks a lot for your videos and take care for yourself. Best regards from Soain.

[@AdrianIII]

Enjoyed especially the comparisons! Thank you!

[@jon4715]

Aegir monoblocks reportedly sound considerably better than in stereo.

[@CaptainCrunch823]

I’ve seen mixed reviews on this topic. Some prefer stereo vs mono Aegir. I suspect it is very system and listening room dependent.

[@jon4715]

@@CaptainCrunch823 the consensus seems to be that mono Aegirs at least don't suffer the traditional drawbacks of bridged mono. less warm, leaner. more detailed. sounds like a similar improvement that the ACA experiences.

[@audiojunkie3089]

I was hoping that Steve Guttenberg had a second Aegir hanging around for an apples-to-apples comparison of the ACAs and Aegirs in monoblock mode. My hunch is they'd be very comparable, thus making the tradeoffs aggregate price vs. complexity of DiY. But maybe there'd be (relatively) starker differences, especially with less efficient loudspeakers.

[@jon4715]

Audiojunkie No doubt the linear power supply in the Aegir makes a big difference compared to the external switching power supply of the ACA. And yeah the extra power of the continuity design will allow Aegir monoblocks to drive small Magnepans. I wonder if there are some good power mods for the ACA.

[@petersouthernboy6327]

Audiojunkie - the Aegir Mono is going to have more balls than the ACA.

[@brandonburr4900]

These kits were already selling like hotcakes at diy audio. Now with Steve's blessing I forsee they will go out of stock again😀 can't wait to build my dual mono diy audio aleph j and f6😀

[@juliaset751]

Steve, the next time you interview Nelson Pass, ask him if he can explain the difference between current and voltage amplification. I was going back over some of your more recent interviews and Nelson said that he was experimenting more with current amplification lately.

[@mitchparker7652]

Thanks for review. I’d like to try to build one. Book on shelf, “The Rest is Noise”, I just looked up. I will eBay it. Seems to be a must read.

[@stephenhylander9395]

Another Great video, Steve! Thank You for ALL of your hard work, and expertise! Have A Happy Labor Day Weekend! Cheers!

[@BlankBrain]

I'd use an electronic crossover to be able to use the Camp Amp(s) to drive compression drivers, then some other decent amp for base.

[@OldTooly]

Doing exactly that myself at this moment. Very satisfying. In fact I went tri amp, low wattage tube on 806a horn drivers , mid wattage tube on 12" (80-880hz), high power Solid State on 15" ported sub. Extremely good setup and so open to tuning for room acoustics and personal taste.

[@seangray3730]

I have one of these coming in January. Wondering if it will pair well with the Pure Audio Project Duet 15 Preludes I have coming in December.

[@trevorhammons1930]

Steve - Id love an in depth comparison of all the first watt amps you’ve used with your klipsch speakers. I have the SIT 3 and would love to hear you articulate the differences with the other amps. Like you did here

[@jsmctch]

The only Klipsch speaker you have is the Cornwall 4... Oh you poor guy, I feel for you

[@NeilBlanchard]

I'm sure you realize that the reason he wanted the smaller Klipsch speakers - is because they are $600 and a much more likely pairing with a low price amp.

[@jsmctch]

@@NeilBlanchard You do realize sarcasm is a thing

[@NeilBlanchard]

@@jsmctch Yes. I am making a clarification of Steve's review.

[@jsmctch]

Oh. Since you did it under my comment instead on the main comment string, and mentioned Klipsch as I did,I assumed you were addressing me and my comment. Thanks for clarifying that.

[@euclidallglorytotheloglady5500]

I believe Steve was really wanting to be able to give insight on a possible very well performing combo for cost of entry. I'm a hobby that you can spend more than some houses chasing a sound, it's reassuring to know some folks that have a well trained ear and the opportunity to test equipment at all price points is doing his best to look out for the one who are not able to drop $4k for a amplifier.

[@brettconsolacion3027]

Let’s play a game. Take a shot every time Steve says “amp camp amp”

[@scottyo64]

Can't do it, I have to work 😫

[@stevefick3919]

I'm not as think as you drunk I am.......

[@ste1040bill]

I did build the ACA back when the project came out - just few days later it was ready in 2012 and still have it . Yes this amps hugs you in stereo . That's correct :-) with a good speaker it just does wonders :-) And I also like , the mid level of amplificatiion wich is 14 db , that is about my taste . Also some First Watt are like that :-) Many many amplifiers , amplify too much to be wasted then into the negative feedback . ACA , has only 9 db of negative feedback , and that is also one of the reasons why it plays music so well . Thank you

[@sarahX..]

would ACA suit a 115db midrange compression horn ?

[@johnlebeau5471]

I am a single ended triode fan. I bought an ACA out of curiosity, I wondered how a single ended transistor amp sounded in comparison to the tubes. The answer was; very close to the organic sound that makes S.E.T.s so seductive. I have a pair of homemade speakers that laugh at the Kornwall's pathetic 102db sensitivity. They are tri-amped with an external crossover and the ACA lives in harmony with two S.E.T.s using the two watt, 45 power tube. The ACA powers my 93db tweeters. It is a fantastic little, in power and size, amp.

[@tassostsoutis601]

Are there any plans online for the speakers? thanks

[@johnlebeau5471]

@@tassostsoutis601Here are the initial plans: www.lampizator.eu/SPEAKERS/PROJECTS/P17/Endorphine%20from%20Kingston%20Kitchen.html This is the commercial version, which you can only buy in Europe: www.6moons.com/audioreviews2/fe/4.html Here is the designers website: www.fikuselectric.com This is the crossover I use: sublimeacoustic.com/products/k231-stereo-3-way-active-crossover I have the RAAL dipole ribbon tweeter, 93db/w/m, an Altec 515b for the bass 105db/w/m (open back and about to be two per side), and for the midrange I use a pair of Altec 203b theater horns with 288c compression drivers 115db/w/m. Active crossover, two 2 watt S.E.T.s using the 45 driver tube on the bass and midrange, neither of them commercial, and the ACA on the tweeters. I have owned the Altec gear for close to 20 years, they cost a lot more now than when I bought them. I have about $4,000 into these speakers, would probably cost at least twice that now. The commercial version starts at 6,000 Euros, $7100. Mine will reach ear bleed levels on 1/10 of a watt, the commercial version is pretty good too but not as sensitive as mine. Mine are huge, ugly, and they live in the basement in a dedicated room. They sound fantastic. Good luck.

[@euclidallglorytotheloglady5500]

I gotta say I'm really excited! I ordered 2 the other day and should be here today! I also have Cornwall IV's and can't wait to do some playing! FYI it only took 2 days for shipping!

[@b97209]

What preamp are you going to use? Do you mind writing back about what works for the preamp after you get some time with it. We have Cornwall IVs too.

[@euclidallglorytotheloglady5500]

@@b97209 Absolutely! I'll be using a Belles 21a tube preamp that I've changed out lifeless Dayton caps for Mundorf Mcap supreme silver gold oil.. It does have balanced outs. I did get the actual ACA's and power supplies today, it looks like the chassis are being shipped out the 7th. I was surprised seeing the delivery notification today, I just assumed everything was going to be shipped the 7th. Anyhow, in the mean time I'm going to get familiar with everything and see about changing up some things to squeeze as much as possible outta it.

[@b97209]

@@euclidallglorytotheloglady5500 sounds like a fun preamp. We got a Musical Paradise 301 integrated and love it. Good luck with your ACA and hope to hear how it goes. Thanks for sharing!