There is pure class A integrated amp called microZOTL 2 from LinearTubeAudio (https://www.lineartubeaudio.com/products/mz2mz2-s). It uses signal tubes only for sweetest sound I have heard recently. It has two inputs but it's only 1W/channel so you need very efficient speakers such as Teresonic http://teresonic.com/magus/. That combination can beat 20K+ systems with the sound quality.
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This may be a very nice integrated to buy used later, linear class-A A/B said to have class-A sounding upper frequencies. And comes with a DAC inside. " I was struck by this combo's shimmering, translucent, finely detailed upper midrange to treble frequencies." https://www.stereophile.com/content/cambridge-audio-edge-integrated-amplifier Cheers George |
Looks like I'm a little late to the party, but might I suggest trying to find a Yamaha R-9 receiver? It has a front-panel button for 'Auto Class A', which gives you about 30 watts of beautiful, pure Class A power (about 15 w/ch), beyond which it seamlessly transitions into Class A/B mode up to full rated power (conservatively rated 125 w/ch into 8 ohms, 20-20kHz @ .015 THD). I've had an R-9 since new, bought back around 1985. The R-9 was Yamaha's flagship receiver, and I've never had the slightest problem with it - built well, and still looks and works like the day I bought it. Currently, my main system's preamp feeds the R-9 to power four sets of indoor and outdoor speakers around the house. The R-9 is especially great if you have speakers efficient enough to keep the amp running in Class A mode most of the time - even those who aren't big Yamaha 'Natural Sound' fans say that the R-9 in Class A mode is a totally different animal. (Just be sure you have good ventilation, or even a small fan - 'Auto Class A' kicks off enough heat to fry eggs on the top of the receiver!) From my experience, the R-9 was a very good, solidly built receiver that just never seemed to get enough respect, especially given its fairly unique Class A capabilities. A quick check on eBay shows several fully functional R-9s going for prices between $75 and $200, although one described as "fully restored" was priced around $1300. A decent R-9 might be a good way to get your feet wet in the "Class A waters" without a mid four-figure outlay. If desired, you could then make a more confident investment into one of the more expensive alternatives, and easily resell the R-9 for whatever you paid for it. |
@krell_fan1 Interesting to contrast your "take" with opinions recently expressed here: https://forum.audiogon.com/discussions/new-krell-k-300i-class-a-ibias-integrated-changes?highlight=300i%2Bkrell |
A really great sounding inexpensive integrated is a Tandberg TIA3012. It’ll set you back $300-350 and is heavily biased into class A as it runs very warm to the touch. I had one for a few years and loved it. Kept it on all the time with about 4-5” of ventilation on top. 100 wpc, MOSFET outputs, very warm and tubey sounding. I would take one anyway over NAD or many others mentioned. Only sold it to go to separates. |
Assuming you meant 85db, not 85hz, you're correct that those are low efficiency speakers and will need plenty of power. It could be class A, but that would cost you a pretty penny, for sure, especially if you go tubes. If you are on a modest budget, considering easier to drive speakers will make things much easier on your amp choice. FWIW, I have 85db Sound Lab electrostatics and also love the sound of many class A amps. I spent over $3k on a used Krell FBP-300, which is a fraction of the cost of other tube amps that I used with the SLs previously. At 85db, you want to be pretty committed to the speakers, as I am, knowing that amp matching will always be important and relatively expensive. Cheers, Spencer |
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@sleepwalker65 If you have gathered anything from this discussion thread, it should be that you have to audition the equipment you intend to buy. Over the years, i have heard great sounding Class A amps and some really expensive awful sounding ones. While you compare the purchase to buying a washer dryer, I would suggest that you are making the mistake of false equivalence. one is purely functional the other a matter of entertainment and enjoyment. Washers and Dryers don't activate endorphins nor do they create harmonic effects or bring back memories. Acquire your equipment as an iterative and involved process. Would you buy a car without test driving it? A piece of art without seeing it? I know you would ideally audition every combination of the gear you're interested in but 1) you would still need to narrow down the gear you're interested in through reviews and feedback and 2) auditioning say 5 speakers, amps and dacs at once and comparing every combination is difficult! So my plan is to build a system based on well reviewed cost effective components that technically at least should work well together. Hopefully that will be the case and I can enjoy it for years without regret, but if not, I can start to tweak it component by component. At least that's the plan. |
I would, budget permitting run and not walk to listen to the latest integrated amp from Krell , the K-300i I heard it in Denver at the Rocky Mountain Audio Fest. As soon as I got home I ordered the Duo 300 XD and it sounds as good or better than my older FPB 400cx. It’s , in a word, glorious and runs on pure Class A but not the power hog of its predecessors. So be careful NOT to buy the original Duo 300. Big difference between that and the new XD version. http://krellonline.com/integrated-amps.html |
if you have gathered anything from this discussion thread, it should be that you have to audition the equipment you intend to buy. Over the years, i have heard great sounding Class A amps and some really expensive awful sounding ones. While you compare the purchase to buying a washer dryer, I would suggest that you are making the mistake of false equivalence. one is purely functional the other a matter of entertainment and enjoyment. Washers and Dryers don't activate endorphins nor do they create harmonic effects or bring back memories. Acquire your equipment as an iterative and involved process. Would you buy a car without test driving it? A piece of art without seeing it? |
Along the lines of vintage gear, if you are willing to veer off the path to class B, NAD integrated amps are famous for delivering hifi sound quality on a tight budget. I’ve gone that route with a pair of NADs (3225PE + 3020i) bi-amped to power my Energy Reference Connoisseur speakers. The results are very pleasing to my ears, and cost only $150 each. |
If you do not need a lot of power and you can find one these rare gems from the 1980's in good working order, you might want to check it out: http://www.hifi-review.com/153440-musical-fidelity-a1.html |
Luxman has made very nice class A amps for decades, Accuphase, Sungden, Pass labs, all these can be had used in your price range if you look and have time. Luxman L540-550-560 are Pure class A amps from the early 80's that are wonderful and can be had for $1k to $2k depending on the condition, the newer ones still may be out of that price range. you should be able to find an Accuphase use for that as well. not sure if pass's integrateds are in that range yet or not. You see a few Sungden integrates in that range as well but harder to find in some areas. then of course there is many tube class A amps but I'm not sure if that's the way your thinking. It really depends like others have said on the efficiency of the speakers you buy. Class A is going to like more then 90db 1w 1m. if you go much lower then 25wch then your into 94db and up. of course that's speaker depended but as a general rule that's a good place to start. one other thing to consider is a class A amp is going to be like a space heater as they run flat out all the time and the high bias causes a lot of waist heat. so something to consider if your in a warm climate. I would not count out class AB like many have already suggested. I do like the look of the kinki audio integrated seems to be a good deal for what you get. |
@pfrank12, the OP mentioned a price point under $2k. A good used Accuphase will cost 5 times that (I own a E600). I would suggest he aspire to an Accuphase which is what I did over the past 30 years. I will agree with you though. The Accuphase gear is amazing and if you find the right dealer, you can work some great deals on it. |
Second the Sudden A21SE recommendation. I own that amp myself. It is immediate in reproduction.... I mean really quick. Everything else seems slow off the mark and a bit sloppy. Midrange is sweet and bass is tight but not thunderous or really deep. Do not shy from the 30 watts Class A. It will drive most anything and scary loud. It does not possess the sweetness of really good tubes, so don't believe that comparison. I run Manley tube gear and it will not compete there, but then it did not cost 14K.....duh. Terrific piece. |
Generally, a class A/B all tube amp sounds far better than most SS amps for comparable money, and one with Pentode/Triode switching will generally sound even better than that, and there are a lot of options for those including relatively inexpensive Primalunas to more pricey Rogers High Fidelity amps...and many in between. Not sure if anybody makes a tube single ended integrated amp, but although generally requiring efficient speakers, that could be even better sounding than most other options. |
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@steakster Yes I’m struggling to figure out how to work through all the possible combinations of equipment I could possibly pair and how to sequence purchasing. I know people say you’ve got to go out and hear stuff but a) you can’t hear everything you’re interested in around you and b) that takes a lot of time. Or are you supposed to max out your card and order multiple amps and speakers and play around with that? Or just do your research and blind faith buy well regarded gear knowing that the system is going to be so much better than anything you’ve owned that you’ll probably be happy with it and if you’re not you can resell it? I’m leaning towards the latter, and leaning towards starting with Fritz speakers and building around that. Then the question becomes how good of an amp do you need with the speakers to where you reach diminishing returns? The one thing I think I’ve got down is the Bluesound node 2i. Seems to be a unanimous choice for a budget streamer with a good enough DAC to get started. Sorry for the tangent. |
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Thanks guys. I’m assembling a system from scratch and have heard so many good things about pure class A. I’m looking at bookshelf speakers in the 2k range. I’m coming from portable audio and I’ve got the LHS GeekOut V2A headphone DAC/Amp which is class A and sounds so good. It’s punchy, detailed and full bodied - by far the best portable source I’ve heard for dynamic drivers (not BAs). |
Agree agree with post about AB amps - my quad qsp power amp had AB power but used A purely for first watts then AB on demand for surge(they call current dumping) - very smooth and detailed . I partnered with valve pre-amp but they make integrated too so may be economical option. The integrated is elite model. |
Class A means very little - a high bias A/B can sound just as good. Most rate their “Class A” rating into a 8 ohm load so if a amp is rated at 50W Class A into 8 ohms - that same amp will only produce 25W class A into a 4 Ohm load. Look into thd Yamaha AS series integrated amps - beyond excellent sounding units. Nelson Pass wrote an excellent paper on Class A amps you can read it on the Pass DIY site good Listening Peter |
Sony TA-A1ES. The amp sounds really smooth and musical. https://www.google.com/url?sa=i&source=web&cd=&ved=2ahUKEwj_26udx5HfAhVj6IMKHfaEAmMQzPwB... |
You could build a couple of these and pair them with a small preamp: https://diyaudiostore.com/products/amp-camp-amp-kit?variant=7072933085218 Otherwise, consider the Sony TA-A1ES. It's more of a quasi-class A, but still gives the class A sound - very smooth. These can be found in mint condition for $1500. Hard to do better for the price. However, it does suck a lot of juice from the wall as do most class A amps. The Belles is class AB. IME, a good class AB amp can rival class A. Though I'd rather have a class AB tube amp than a class A solid state amp. You must also consider the long term cost of class A amplification. My electric bill was about 30% higher when running that Sony integrated (3 hours/night), despite its greater efficiency than typical class A. |
This is <200 and supposedly pure class a. Anyone heard it? https://www.aliexpress.com/item/Finished-classic-HIFI-Hood-1969-gold-seal-Class-A-amplifier-HIFI-EXQ... |
There is a Sugden A21SE listed here for $2199. You should make an offer on it! https://www.sugdenaudio.com/a21se-integrated-amplifier |