Review: Mystere ia21 Tube amp

Category: Amplifiers

First a little background. About 3 years ago and roughly 20 years into this crazy hobby I really changed the makeup of my system by forgoing the separate amp, preamp combo in lieu of an integrated amplifier. Pursuing the "simpler is better" principle I discovered that in my system I was getting better sound, dollar for dollar, than with separates. Now I’m talking about separates that cost 3 to 4 grand a piece vs integrated amps of the same combined value. To date the integrated amps I have used include the McIntosh MA2275, Rowland Concerto, Edge G3 and the subject of this review the Mystere ia21 which comes from the makers of Prima Luna; all of which I really enjoyed, just some more than others. With all these integrated amplifies the rest of the system has remained relatively unchanged: JM Lab Mini Utopia speakers, Ayre CX-7e CD player, Kimber 8TC speaker cables, Audioquest Cheetah interconnects and a PS Audio modified P300 power regenerator all plugged into a dedicated 15 amp circuit. My listening room is 24’ x 13’-6” x 8’ and is a relatively live space with area rugs over hardwood floors and gypsum board walls and ceiling.

I can get a little long winded when it comes to describing the sound of audio components and I will eventually talk about the Mystere so feel free to scroll on down to that review if you like but I first want to give my impressions of the other three integrated amps I have been fortunate enough to own and use over an extended listening period of anywhere from 6 months to a year and half. So you will find this is more a review of all four integrated amps I have owned over the past few years. As you read through my descriptions of the aforementioned integrated amps be sure to keep in mind the context of my system and room makeup mentioned above. All the integrated amps have been of relatively modest power with the exception of the Rowland so my 91.5 dB efficient JM Lab Mini Utopias have really played an important role in the sound quality I have achieved in what can be considered by many on this site as a relatively modest high end system although still crazy expensive to the uninitiated.

McIntosh MA2275: This was my first integrated amp and like the others I really enjoyed it but it was very different from what I was used to, in particular the Pass Labs X250 amp and X1 Pre I sold to fund the purchase. To this point my preference for sound was to achieve a very pristine, tight and spacious sound. Dynamics and dynamic contrast were and still are very important to me. What the MA2275 did for me is introduce me to the world of tubed power amps. I have owned tubed products in the past but they have been preamps and while you can get a good flavor of tubes with a pre there is nothing like power tubes to make you understand what tubes are all about. The Mac had a bold sound with a great deal of body and weight to the midbass that I had been missing in every single solid state amp, preamp combination I ever had. The Mini Utopias are limited below 35 Hz so that midbass roundness was a nice complement, but I wouldn’t exactly call it “tight” bass though. What I found most appealing with the Mac was the spaciousness and sparkle it gave to individual sounds, apparently one of the great traits of tubes. There really was the sensation of hearing sounds with a breath of life in them, again something that has always eluded the solid state purchases I have made in the past. This combination of rounded bass and high midrange sparkle was great with many types of music but rock and pop really seemed to suffer the most, specifically with the bass and in particular with electronic pop and rock music (Propellerheads and Moby for example). It just didn’t have the drive required for that type of music but that really wasn’t a surprise to me, I sort of expected that with my limited knowledge of relatively low powered tube amps. I know looks should not be considered when evaluating sound quality but man I really dig the cool look of the Mac. It makes me think of a vintage Cadillac with tail fins, very retro cool.

Rowland Concerto: I traded the McIntosh MA2275 for a Rowland Concerto integrated in the hopes of getting back some of the power that was missing when playing rock and pop. The Rowland is 250 watts and it introduced me to the world of Class D switching amps. The power was definitely back but missing was the sparkle and that breath of life that was so appealing with the Mac. I don’t know if I was just made more aware of that because I was switching from the Mac to the Rowland or if indeed the Rowland was lacking those qualities even compared to good solid state. In retrospect it is probably a little of both but maybe even a tad more of the latter. I have never owned a component that was as cable sensitive as the Rowland and I have since heard that many class D amps are cable sensitive due to the high amount of RF they can emit. So for me I spent a great deal of time trying to find the perfect interconnect for this integrated amp and ultimately chose the Synergistic Research Illumination shielded cable with really good results. Kimber Silver Streak, although beautiful in other system, was a little on the brittle side and Cardas was a little too dull sounding. I will say that this was probably the most top to bottom technically impressive sounding integrated amp of the lot and on paper should probably be the sonic winner of all of them but for me it was probably my least favorite of the integrated amps I have tried. I think part of the problem was the Rowland should be mated with a full range speaker, not the Mini Utopias that I have, to really reap the benefit of the Class D circuit and its control on a speaker’s woofers. The bass I did have with my JM Labs was very tight indeed though. I bet it would have been a much better match with my previous speakers, Hales Transcendence 5’s albeit with that lack of sparkle, high end extension and fullness.

Edge G3: Once again I made a trade but this time it was the Rowland for a 115 watt Edge G3. I was going on the reviews for this selection and I must say the Edge ended up being a fantastic solid state integrated with yet another different sonic signature but I would say somewhere between the Mac and the Rowland in sonic personality. It was very open sounding with a huge sound stage. Actually one of the biggest sound stages I have heard compared to any amp, preamp or integrated I’ve used in the past while voices and instruments were solidly placed within the sound field. Bass was very tuneful, fast and tight. All in all very “accurate” sounding. The sense of space really struck me with this amp particularly mated with the Ayre CD player but it still lacked that tube magic. But based on the other things this amp did right it was a really good ride for the year and a half I owned it. In fact to this point I would say the Edge G3 was the best sound I have obtained in my system with my musical preferences which really is all over the place including pop, rock, bluegrass, classical, alternative, indi, some alternative country, jazz and acoustical. All were recreated quite well. As a side note the Edge G3 looks much better in person than in pictures. When I first opened the box I was struck by how handsome a product it really is.

So with the Edge being such a fantastic amp why would I move on? Do I really need to answer that question? The quest for the BETTER! With the Edge I had sort of arrived at what I considered to be my preferable sound and I really did settle down with it. But something started to happen. Yes I had the sound I thought I always wanted but in a way it became a bit sterile. Technically superior with that pristine, spacious and tight sound that I have been looking for but emotionally not quite the connection with the music like with say the McIntosh I had a few years ago. Yes the Mac had its faults but there is something emotional with tubes. As a result I began listening less and less with each passing month until I really stopped altogether except for maybe an album or two a month if that. I still listened in the car quite a bit and at work through cheapo headphones but my free time dedicated to listening at home was really replaced by TV. That’s not good. This could be a result of just getting board with a particular sound and would have happened with any component I spent a significant amount of time with, or was I indeed in conflict with what I thought was THE superior sound (within my price point I must add)? I think it was the latter. I found this distressing because of the implication that maybe it’s good sound I’ve been after with home stereo and not necessarily good music. Again not good.

Mystere ia21: Right off the bat I’m not going to suggest the Mystere is a life altering product, not quite, but it has certainly brought a fresh perspective to the music I listen to. I’m not even 100% sure why I bought the Mystere considering there is not that much on it in the way of reviews or even user comments, but I think mostly it was the want of getting back into tubes, particularly the KT88 power tube that the Mac used, the reputation and reviews of the Prima Luna products (again the same guys behind Mystere) and what little information I did find describing the unit as having more drive than the typical Prima Luna amps and integrated amps. That lack of drive with some music was one of my faults with the Mac.

Here are some deal breakers for many I’m sure. First the Mystere does not have a remote, not even for volume. Second the volume is stepped so if you are one of those guys who has a hard time finding that right volume you may have a problem with the 24 steps. Third, it’s only 50 watts per channel. Fourth, no balance control. Just four line inputs and volume, that’s it. Oh there’s the EL34/KT88 bias switch which allows the use of both types of tubes but that’s it in the way of creature comforts. Oh yeah, it’s dead sexy, no way around that, absolutely gorgeous with the black lacquer finish, glass tubes and dab of stainless steel accents. This is the only piece of stereo equipment, EVER, that my wife wanted left out in the open. Packaging is nice with the unit TRIPLE boxed with ribbed white gloves included, but no owner’s manual. Jared and Kevin at Upscale Audio were great to deal with during the transaction as well.

-As I write this it is Saturday December 13 and I have just today received the latest The Absolute Sound (Issue 189) and what’ya know right there on page 96 is the ia21 being reviewed. There goes the wind out of my sails. I’ll talk about the TAS review shortly but first I want to keep going with my impressions of the Mystere ia21-

After letting the amp acclimate to the temperature of my room for 24 hours (it was close to freezing when UPS delivered it) I turned it on and let it warm up for 15 minutes or so before playing any music. The unit is dead quiet. No noise from the integrated and no noise from tweeters, good start. Oh, I should note that I left the tube cage in the shipping carton, it just seems like the tubes would bake with it on. Upon first listen with the Mini Utopias connected to the 4 ohm taps the sound was very similar to what I remembered the Edge G3 sounding like except a little bass shy. The Edge was long gone (2 weeks) by the time I got the Mystere so I couldn’t do a direct comparison. Seemed just as detailed. High frequencies seemed just as sweet as the Edge but in all honestly I guess I was hoping for more. Spatial resolution seemed very similar as well. It was really nice sound but I wasn’t quite hearing any tube magic yet and I concluded that some amount of burn-in was going to be required. Jared at Upscale Audio suggested 100 hours and that’s where I started doing most of my listening.

The Absolute Sound titled their review for the Mystere “Big, Bold and Beautiful”. I couldn’t come up with three better words for a quick description of the sound then that. After a hundred hours or so I really began to notice the influence of the tubes on the sound and while it didn’t quite have the sparkle of the McIntosh MA2275 it without question had that breath of life. Bass is about what I expected from a tubed integrated amp which is to say similar to the Mac put perhaps just a little lighter and tighter (but boy it’s been close to three years since I’ve had the Mac so I’m going on memory). I switched to the 8 ohm taps and got a slightly different flavor. In fact it was everything I just described with the 4 ohm tap but a little more. Mid-bass was a little fuller and rounder but I wouldn’t describe it as loose, no, quite the contrary. It seemed properly scaled with the rest of the spectrum. What I attributed to the “tube sound” with the 4 ohm tap was slightly more in evidence with the 8 ohm tap.

Here is what I find killer about the amp, its rhythmic drive and its big sound. It literally propels the music out of the speakers, and my Mini Utopias seem to be the perfect compliment. They are very much a neutral instrument that really allow the upstream component’s signature to come through. If the equipment is bright the Mini Utopias are bright, if they are warm then the Minis are warm. It feels like I’m getting three-way speaker fullness and extension with two-way speaker benefits in transparency and spatial resolution. I can’t imagine my old Hales Transcendence 5’s being a good match with this amp though. I suspect it would sound pretty slow with its 10” woofer and 86 dB efficiency. I’m thinking decent efficient speakers (90 or better) with smallish woofers, say 8” or less and I say this in light of what I read in the TAS review and the damping factor of the amp with larger woofers. I’m speculating but I would think Focals, Triangles and older JM Labs would be killer with this. I would love to hear the Mystere with a Focal Micro Utopia BE or Diva Utopia BE.

It seams Mystere has made great attempts to keep the unit minimal, like the stepped volume control for example that has only one resister in the signal path at any given volume setting and point to point wiring which really allows for a very transparent sound, again a really good match for the qualities that folks find beneficial in two-way speakers with simple straightforward crossover networks.

So I read the review in TAS and the strange thing is I concur with a great deal of it. Why is that strange? Well, even though I try not to put too much credence in the way of reviews I can’t help but rely on them particularly for purchases that have the potential for costing me thousands of dollars. So here’s the strange part, had I NOT purchased the Mystere before reading the review in TAS, I more than likely would NOT have purchased it simply based on the one review. I would have moved on to something else say a Cayin or a Prima Luna integrated and save a few bucks. So if I agree with the review and had I read the review before buying the Mystere does that mean I shouldn’t have bought the ia21? Well, no. Here’s why. Some of the descriptions used in the TAS review are descriptions I would associate with sound qualities that, for me, would not be desirable. Wooly bass for example. I can’t stand loose bass, the kind I associate with cheap home theatre demonstrations or those cars where the occupants try so desperately to get you to enjoy the music they are listening to. I would much rather do without than have bad bass, this is one of the battle cries of the two-way speaker crowd. But as I mentioned previously it is the fullness of the midbass that is making for such a balanced top to bottom sound in my system which seems quite different from what was reported in TAS. This obviously would suggest system synergy and matching is crucial.

Is the Mystere “accurate”? I don’t know. If my old Edge G3 is “accurate” then no. If my old Roland Concerto is “accurate” then definitely no. In fact if you are in love with the Roland Concerto then forget about the Mystere, it won’t be for you. I suspect there is added color but I won’t go so far as to say it is colored. The color is what gives this thing life. It makes it pretty fun. I must confess I did tell a little lie in the review of the Mystere. The truth is I did not use the Ayre CX-7e CD player with the Mystere like I did with the McIntosh, Rowland and Edge. I sold the Ayre about a month ago. I’ve been using a $90 Sony DVD player as my red book player and getting the results I have mentioned. I think if I had used the Ayre it probably would have sounded tidier and even more spatial. I have a PS audio Digital Link III with the Level 4 Cullen Mod coming so I’m really anxious to hear that combination. The Mystere is still new to my system and I have only been seriously listening to it for a couple of weeks so further evaluation is needed particularly in light of the new digital source.

OK, you got relatively efficient speakers, maybe two-ways, or three-ways with smallish woofers, and you find yourself needing more “life” to the sound. Listening to your system is a little sterile. If dynamic contrasts, detail, transparency, big sound, palpable images and seductive midrange are important to you, give the Mystere ia21 a try. The fact it only has 50 watts has yet to be an issue with the dynamic drive the unit has and the way it propels music out of my Mini Utopias (the Mac was shy on the dynamic drive thing so as a result the 75 watts just didn’t cut it for some of my music). The fact it doesn’t have a remote, well I can’t answer that for you. I will say I used to fidget with the volume a lot when I had remote control. Now I don’t. The last I saw the list prices are as follows: the MA2275 is $6,000, the Rowland is $6,000, the Edge is $7,000, the Mystere is $3,000. Regardless of cost, for my musical tastes, with my system, the Mystere comes in first of the four integrated amps listed with the Edge coming in second. I think the Edge G3 is great but I think the Mystere is more fun.

The following are the CD’s I used in most of my listening with the Mystere ia21 integrated amp: Moby “Play”, Leo Kottke “One Guitar, No Vocals”, Beck “Mutations”, Beck “Sea Change”, Beck “The Information”, The Shins “Wincing the Night Away”, The Shins “Oh, Inverted World”, Alison Krauss + Union Station “New Favorite”, Ricky Skaggs and Kentucky Thunder “Instrumentals”, Donald Fagen “The Nightfly”, K.D. Lang “Ingenue”, K.D. Lang “Even Cowgirls Get the Blues”, Radiohead “OK Computer”, Radiohead “The Bends”, Seal “Seal”, Tori Amos “Little Earthquakes”

Associated gear
JM Lab Mini Utopia Speakers
Ayre CX-7e CD Player
PS Audio modified P300 power regenerator
Audioquest Cheetah interconnects
Kimber 8TC Speaker Cable

Similar products
McIntosh MA2275 Integrated Amp
Jeff Rowland Concerto Integrated Amp
Edge G3 Integrated Amp
Nice review. I've always been a big fan of PrimaLuna products so I've been very curious to hear what people think of this new line.
Thanks for your review of some very interesting and much desired units. I too have a liking of integrated amps. I could not but wonder how a Mac SS would have fared. Perhaps giving the magic of tubes with the bold drive of solid state. That is what I have found with my Mac 6600, a awesome unit. In the real world use, I have come to appreciate units, such as Mac's that have usefull features and a good number of inputs and outputs. Happy listening and Happy New Year to all!