This unit is one of the state-of-the-art products that I have listened to. Is it the absolute best? Only you can determine that for yourself. You have to try this out on the speakers of your choice. Not every speaker will perform well with this unit.

Simply put, the CARY 300 SEI is the most musically engaging amp I have ever owned. With due admiration and respect for all my former amps: [Krell KST-100, Audio Research (ss) , Audio Prism Debut, Rowland Model 3's, McCormack DNA-1, NYAL Moscode 300, et al.) and preamps: (Klyne 6L, Aronov PY-100, Audible Illusions 2B & 2D, Mod Squad Deluxe Line Drive, Melos 110B, Coda -02, Audio Prism Mantissa, etc., ad nauseum...) - the simple, unassuming SEI outdid all of them in the one critical area that matters most to me: harmonic structure and timbre. Any good amp should allow a knowledgeable listener the ability to tell the difference between a trumpet and a cornet, or an oboe and an English horn. The CARY SEI goes a step further: it allows the listener to recognize the different MAKES of trumpet, or saxophone, or piano, etc. that performers are playing. 'Know what a CONN "Lady on the bell" (Bird's horn) alto sax sounds like? How about a Selmer MarkVI? A Yanigasawa??? If you know the difference, the CARY SEI shows it to you: all of the subtle nuances, timbre, overtone structure, free of electronic artifacts that obscure tonal subtleties. A piano playing musician friend, listening to several solo piano recordings, kept shaking his head in disbelief as he muttered "Steinway... Bosendorfer... Steinway... Bosendorfer... how easy it is to instantly recognize different piano's"!If you are not into playing "Guess that instrument", put on the Stereophile test CD track that samples the different microphones that JGH ("in whose ears we trust"... pause for slight, reverent, lowering of the head...) delivers his speech "Why HI-FI Experts Disagree". Any of the aforementioned amps and preamp combinations I've owned have had trouble picking up the differences in some of the mic's that were pretty darned close in pickup characteristics. The CARY SEI enables you to clearly hear the differences among each and every one, regardless of how "close" they are. As remarkable as the CARY 300 SEI is in replicating harmonic structures, it is equally up to the task of recreating a musical soundstage with depth, width, and space. Oh, that space! That incredible single-ended-300B-triode-class A space! With the SEI, there is no harshness, no hardness, no artificial "x-raying" of the music to squeeze out every last detail that leaves the listener with a sterile, antiseptic, overly-analytical portrayal that is the sonic equivalent of taking a Rembrandt oil and turning it into a watercolor. The musical richness, the life-blood of the music itself, is presented with an unassuming ease and naturalness. This is an amp that is worth purchasing first, and then going out to look for a pair of speakers that will do it justice (of which there are several). Does the Cary have any weaknesses? (All electronics do, we all know that...) Well, don't expect it to put out the "kick in the chest" bass slam of the aforementioned Krell, Rowland's, etc. Also, if you need a tape output, the 3 line level inputs (no outputs) may not be to your liking, and you can't separate the pre/power stages. Additionally, 300B's aren't cheap (but get good ones with this amp, please; if not WE's then Svetlana's come highly recommended). The fact that it happens to be a tube amp shouldn't scare you away. All hard-wired, no circuit board with lots of little "thingies". The only amp failures I've ever experienced were with ss amps, never a one with a tube amp. The CARY SEI is simply a musical revelation. Five stars, plain and simple...

I agree with Richard G's comments regarding the Cary 300 SEI. In addition, I am using the unit with the optional Cary SE Capacitor Bank. This adds much more capacitance to the power supply, improving the sound even more than it already is!!. Tighter bass and unbelievable soundstage depth and width. Just ask Kirk at Cary Audio. He designed the capacitor bank himself for his local HiFi club. When Dennis Had, head man at Cary, heard the difference, he said it was a whole different amplifier.
And of course, to bring out the true magic of this unit, you MUST use Western Electric 300B's. Since they last longer in addition, using them is a no brainer. They sound that good!
Cary is now producing new 300 SEI units specially designed for the KR 300BLXS tube. This tube is like a 300B on steroids. No more soft bass, 20 watts output per channel, but maybe (comment welcome here) not having quite the magic of the WE in the midrange. Chacun a son gout, as they say in France. Check with Cary regarding availability of the older 300B designed units. You can use the new KR tube in the older units but all the qualities of the KR tube won't come out. The new circuit is specifically designed for that tube. (Older units can be ungraded for the KR tube, at the Cary factory).
5 easy Stars.

After auditioning the Cary 300S SEI at a dealer's place, I must say that I'm quite disappointed at the type of sound that they produced.
Even with the Soliloquy speakers, the mid-bass and bass sounded thin. This is very unlike the many other single-ended amplifiers that I have heard and owned. My present Audion SilverNight trashed the Cary out of the waters anytime; I know because I did bought a pair of the Soliloquy 2A3s from the dealer. The 7½ watter is much warmer and has much more body and space than the Cary. The same thing applied to the Cary 300B SEI equipped with the KR300B XLS tubes. This new amp has more bass but the typical thin and lifeless Cary sound still preveals.

Given the Cary's high price, I really don't see what the big fuss is all about. The same money can buy one the AudioNote Meishu which is significantly better.

Indeed, the 300B SEI is really much ado about nothing. I don't understand why the reviewers over in the States are all crazy about it - either they have not heard a good 300B amp (like the Audion or AudioNote) or they are real professional liars.

A maximum of 2 stars.

Having written a previous opinion of the Cary 300SEI, I forgot to mention that the Spendor SP-100 is a wonderful match for speakers. High sensitivity and impedance allows the 300SEI's magic to come through with most music. The best word for this speaker is NATURAL. You find yourself drawn into and listening to the music, not the sound. Highly recommended.

Having been seduced by numerous glowing reports (Stereophile, Fi, Hifi News, online magazines, etc.), I decided that I must hear these hifi-destroying, music-making SE amps. I too, was initially impressed with the tangibility of the musicians, and the ebb and flow of the music, which is what I wanted. I was really hoping that here would be a range of amps that I could just fit and forget, apart from changing the tubes every so often of course.
I can't tell you how disappointed I was. I visited a dealer in the UK, and he proved to be very helpful, but completely deaf to the clipping/sluggish rhythm problem that you described. As the main dealer, I was assured that all partnering equipment would complement these SE designs well, and this initially seemed to be the case. However I was astonished that this dynamic short-coming, and must further disappoint you by telling you that I was listening to the new KR Kron 20 watt version of the integrated amp (the monoblocks were away being reviewed by Martin Colloms). He did point out that the mono amps should deliver greater control in musically demanding passages, but quite frankly, I'm not so sure and I don't feel like investing so much money in a product that will only play certain types of music - I listen to EVERYTHING, and could not consider myself a musician and music-lover if this were not the case. The 805s are good but produce a significantly different kind of sound, but not necessarily better. They sounded muted when compared with the 572s (too harsh) and the 300s (excellent but haevily flawed). I don't get on with horns.

I, too, have heard the Pass Aleph 3 amp and found it superb - even though I was actually hoping that I might find a tube amp that would surpass its ALL-ROUND performance at a similar price level, whilst delivering that fabulous sense of presence the Cary amps can soetimes produce. It (the Aleph) is a design that I keep coming back to, and am most likely to purchase (albeit a different model, maybe the Aleph 5 or Aleph 2s). I have heard great things about Blue Circle hybrid amps (SE, two stage, zero-feedback, tube and bipolar poweramps) but they are not available in the UK at the moment. Present speakers are Audiophysic Virgos (friendly impedance curve, 91dBw sensitivity), proposed preamp and source, Audible Illusions 3a(?) and Naim CDSII with XPS (an outstanding, reference design). I use Nordost cables.

I, for one, am glad that I'm taking my time with this part of my system. If you have broad musical tastes and like your music to go loud as well as soft, please beware! I really wanted to love these amps.

Jazz/Chamber: *****
All music: **
Disappointment: ******
Justin