Duetta – a dream of a loudspeaker
Martin fulfilled his desire for something special to play back his music, and he wrote us a wonderful report about his subjective sound impressions.
I’m an old hand at hi-fi equipment – today people would say “high-ender.” But since even that term is no longer what it used to be, I prefer to describe myself as an audiophile. What that means: because of my budget and my listening experience, I was always looking for the best possible way to reproduce recorded music. Sometimes more, sometimes less. In my youth, I was proud of my NAD 3020. That was then. Now I’ve ascended to heights that sometimes cause people to make an energetic twirling gesture with a finger next to their temple. But that’s how it is, my hobby. Once you’ve caught the bug…
Be that as it may, what I actually want to point out is that my evaluation is based on components that – in my opinion – are capable of reproducing even the subtlest details of the recorded sound… assuming that the sound engineers, recording and pressing technology allow it. Ultimately, the issue is not so much finding the better loudspeaker, choosing the perfect cable or answering the ever-present question of whether a record or a CD is the better reproduction medium. If the sound engineer botches the job, even the latest Blu-ray player won’t help, unfortunately. But let’s forget about that for now.
About my components:
I play CDs through an Audiomeca Mephisto II with a souped-up power supply and an external 128kBit DAC with selected components. I use an Octave HP500 SE as a pre-amplifier, and the corresponding Octave MRE130 monoblocks for the output. I run them on matching KT88 Gold Lion tubes (the tone is rounder, and they have a deeper bass than the original tubes). The MRE130s have Hoffmann SBBs (Super Black Boxes) for improved power reserves. Basically, each one is a separate box with a whole battery of capacitors. So it’s a potent power source for demanding sound converters, even though – something I should mention at this point – the Duettas are not the most demanding of sound converters. Especially with the impedance correction in the crossover.
The power supply for all the components comes from a power cord connected directly to the in-house distribution cabinet, with its own melting fuse. The wall socket is made by Furutech, and I use a PS-Audio Power Plant Premier for the power strip. It’s a fairly luxurious power distribution system, I admit. All of the cable connections, whether for the power supply or Interconnect, are from the Silent Wire Reference series.
So you can see I belong to the genre of “cable fetishists.” In addition, though, there are also several serious and less-serious measures for tuning devices and listening rooms that fully discredit me and mark me as a follower of voodoo and esoteric practices. In a sense, it’s the “coming out” of every high-ender (with thanks to Mr. Kirbach from the magazine STEREO). During my listening sessions… um, I mean my occult voodoo ceremonies… I use such obscure components as a disk demagnetizer, room resonators (singing bowls) and even a Schuhmann resonator, and I don’t shy away from beveling the edges of the CDs (*eek*). Just incidentally, that’s one of the most effective tuning measures, since it dramatically increases the three-dimensionality of the disks, and every recording fundamentally loses its digital hardness. It’s definitely NOT my imagination. I like to call it analogizing the recording. The only problem: it takes some effort to get used to the idea of putting the sickle to your beloved recording media.
For the sake of completeness, let me just mention that my listening room is also sound and listening-optimized through carefully placed acoustic foam mats. So anyway, without fanning the flames of the usual theological and intellectual debates that always flare up about these metaphysical-seeming tuning measures… you can see that I pursue my hobby with a great love of detail, and that I’m not afraid of obscure experiments. Because it’s a hobby. And it’s fun to experiment.
Let’s get to the real subject: the sound converters:
Until now, I used speakers called Reference 2 (manufacturer’s name removed by the editor). They’re excellent speakers if you primarily listen to pop and rock music. The sound is crystal-clear and crisp, they have a full, gnarly bass, and they never sound over-exerted at high volumes. The only annoyance might be a neighbor or your wife emphatically asking you to turn down the volume. In addition, Reference 2s are completely sufficient in terms of the electronics they use. I never had to move the volume knob past the 11 o’clock position.
As an old and/or former electrostatic speaker fan, what I especially liked about the References was how they illuminated the room in a wonderful three-dimensional way, untangling even the most complex musical happenings. The speakers never lose their overview, even for very large orchestras (e.g. the Clevelanders) in the loud sections of a forecful Tutti…
somehow I was never really satisfied with the sound of the speakers.
Well, because I’m NOT a pop and rock fan! That’s the main reason. I’m an out-and-out classical and jazz listener. So the quality requirements for my loudspeakers are different – I’m not looking for bone-dry basses and crystal-clear high notes even at ear-damaging volumes. In that sense, these top-rated high-priced converters were a classic purchasing mistake for me, and at the same time they clearly proved that there’s no ONE perfect speaker. Listening is a very subjective thing, and ultimately it is also closely tied to your own preferences. It doesn’t matter what the various testing magazines, with their point systems, might suggest as the top rating. It doesn’t matter how objective you think these trade journals are, or whether you think their opinions have all been “bought.” The fact is, listening and listening preferences are subjective through and through. Even for an editorial staff. Anyway, to cut a long story short: for a violin or a brass instrument, the Reference 2s sound(ed) too superficially clear (to me), with an excessive focus on the high notes. At first listen, they sound nearly perfect and overshadow everything around them. But in the long term, they were much too sharp for my ears, with exaggerated clarity. The longer I had them, the more I noticed it. Although it should be said that it might have had more to do with a lack of symbiosis between the acoustics in the listening room (concrete ceiling, wood floor, stone walls, sparse furnishings) and the speakers. In any case, it was time for something new…
During my extensive search for new speakers, I was actually just about ready to buy myself some heinously expensive pieces. We’re talking Avalon Eidolons or something in that category. But the exorbitant luxury price kept me from taking the leap. (Or was it possibly my wife??) Then a music fan and fellow sufferer told me to look up a speaker called the Duetta online. He said the reviews of the assembly kit were very positive.
Duetta? Do-it-yourself? Me? That’s crazy!
After all, I was looking for the ultimate sound converter. Not for some novelty speaker from the crafts corner. It reminded me strongly of my first serious experiments in the field of hi-fi. Back then, too, girded with a drill and a saw, I had installed mostly Scandinavian drivers into wood cabinets. It was fun, and much cheaper than buying the originals, which were much too expensive for my wallet at the time.
In any case, after extensively studying various entries in the online forums, I made initial email contact with Udo. I should say here that it was a very eye-opening contact. I quickly realized that this was NOT one of your typical “Commercial speakers are all overpriced and I can give you much better performance for much less money” spiels. No, our conversation was actually very serious and informative. It was easy just to indulge in a little shop talk with him and compare listening experiences. In any case, he not only shared/confirmed my own opinions about the Reference speakers, but provided me with a specialized technical explanation. That created a huge amount of trust.
Once I started playing around with the idea of building a cabinet for the Duetta assembly kit that looked anything but homemade, Udo gave me extensive help with the implementation and answered all of my countless questions at lightning speed. And – this should also be emphasized – I had not yet bought a single component from him at this point. It was really great.
(Editor’s note: Martin created these drawings and was kind enough to let us publish them. Neither we nor he can assume liability for any measurement errors. A larger image can be downloaded here as a Zip-file.)
The cabinet itself – you can see the homage to the Avalon Acoustics loudspeakers – was made by a cabinetmaker with a CNC router. Before making any attempts to reconstruct this project, be warned: these cabinets are a curse! There is not a single right angle or parallel wall. Creating this cabinet probably cost my cabinetmaker several years of his precious life, and it is probably one of the main reasons that Avalon speakers are so expensive. It all has to do with the cabinets.
Anyway, now we come to the important part...
Was my (repeated) blind purchase worthwhile?
My sense of anticipation was predictably great. My first impression after assembling the chassis and crossover: it works. Sound comes out. Nothing is exploding, nothing sparking or smoking. But the sound that came out of the converters was less than satisfactory. Everything sounded very, very two-dimensional, fairly compressed, and even the highly praised tweeter sounded fairly papery to me. Okay, I thought, no big surprise – I just switched on the components, so this is like an initial startup. The system hasn’t warmed up yet, so you can’t expect it to sound good. But was the oft-cited potential really in there? As I said, listening is subjective. And of course it’s very dependent on the components and the acoustics in the listening room, and on your own listening habits. But setting aside the odd adjustment here or there, it wasn’t at all what I was used to. It sounded more like a cheap Chinese import than high-end equipment. Since it was already getting pretty late, I set the CD player on repeat and left the system running overnight. The next day I would have my first real listening test.
My furrowed brow wasn’t completely gone, but the second listening impression was already much better. The reproduction now offered a kind of spatial depth. It was still clearly behind the 2DC, but there was some development at least. It wasn’t a mashup of sounds anymore, but now there was a clear left-right differentiation and the instruments were easier to locate. A clear sign that the speakers needed time to warm up. Plenty of time, as Udo later confirmed for me. You needed to give the drivers 100 hours before they would play with complete freedom. I can absolutely second that, in retrospect. In any case, it was clear to me after the first listening session that I would need to play the Duettas constantly for a few days and nights. And that’s exactly what I did. So what was the final result after about two weeks of breaking them in? (Drumroll, building tension…) I now have exactly what I was looking for. A loudspeaker that not only looks great, but also sounds much better than anything I had in my listening room before. I have my dream loudspeaker! It might sound like an exaggeration, but it’s not. Would you like a longer explanation?
Okay, maybe this is the best way to describe it: the Duettas have a built-in ear-flattering feature. That doesn’t mean a diffuser that makes everything sound washed out, powdery and soft. No. The high notes are silky and clear, but without any trace of hardness. In particular, the snapping, clapping and hissing sounds come through very subtly and without any agitation. They lack the sharpness I’m used to hearing, and the messy hiss of a metal or woven calotte. In fact, I’ve never heard the “psst” sounds in the opening sequence of “El Canto de la Sibila II” (Auvidis 1996, Jordi Savall, Montserrat Figueras) come across as naturally and subtly as they do with the Eton ER 4. It’s an exceptional converter. Absolutely. Even unpleasantly brassy trumpets and trombones (same CD, track 21) are downright fun with the Duetta, and the voice of Montserrat Figueras is pleasantly assertive but never metallic, harsh or throaty. Representing a voice in a silky soft way without losing its intensity and especially its authenticity – that’s impressive. It’s as if she were standing right there behind the microphone, and the microphone is the only reductive technical link in the chain. The calibration with the 7-360/37 HEX – which is key in this interaction – seems perfect. So praise is also due to the mid-range speaker, not just the ER4. While Figueras has breath, a body and stature, a plucked lute has a clearly “visible” resonant body made of wood. And the plucked strings sound so soft that you are willing to testify they are made of natural gut. Overall, you don’t have the sense of listening to a sound recording. Instead, you are observing the performance behind the microphones. Everything has breath, a body and air, and above all plenty of space. The church is illuminated down to the smallest corner, and the missing room depth I mentioned earlier is completely gone. It is the same fantastic room depth that also distinguishes the Reference 2DC. In contrast to those speakers, however, the action is slightly more in the foreground. Not so far behind the speakers, in other words – closer to the listener. And – I think because the Reference basses are positioned on the sides – the image is reproduced more narrowly between the speakers. Whether one or the other is more “correct” can only be determined by a direct comparison of the live performance. But everything is wonderfully three-dimensional, and all of the sounding bodies are sharply focused within the room. A concert piano comes across more realistically than I would have believed possible in my chain of equipment. It felt like I could reach out and touch it. That is how it’s supposed to be.
Now for the bass of the Duettas… It isn’t as powerful as the one in the Reference. But it is deep and very precise, which is clear especially when you hear quickly struck kettledrums or bass drums. The Duetta is a little more reticent here than the 2DC, but that also means it is less aggressive and more pleasant. Not that there’s a shortage of bass. No way. But the sound waves don’t knock you over right away. They aren’t the kind of acoustic waves that give you a new blown-out hairdo. The focus is not on the effects, but on the music, which rightly has the greatest impact. Everything is just conspicuously inconspicuous. In a sense, the loudspeaker doesn’t even exist. You don’t have the feeling of hearing a loudspeaker. It isn’t there. And in reality, THAT is the goal of every audiophile. That is how it should be. The calibration is round, uncomplicated and harmonious. I think that’s exactly what Udo’s earlier “tinkering” with the Duetta crossover was meant to achieve. Whether it uses a film capacitor or an electrolytic capacitor, the result was/is what counts. Not the name. And from my perspective, the crossover is perfectly calibrated. The Duetta doesn’t reproduce sound, it plays. It has a clear overview and maintains it even in loud, powerful passages (Orff, Carmina Burana, Deutsche Grammophon 4D). In a choir with many voices, you can still clearly pick out the individual singers and their positions without having the sense that the Duetta is dissecting the music with a scalpel. The music is still part of a whole. There are no breaks. It is not glassy and transparent, nor wooden and stuffy. The loudspeaker and the musical performance simply have fusion, body and plasticity, as high-enders like to put it. The resolution is just as good as in the Reference 2DC, but it sounds much softer, more natural and smoother in my listening room and to my ears. I am more than just satisfied with my Duettas. I think – I hope (!) – that my speaker issues have been solved for the time being. Compliments to you, dear Udo. Even though I refused to listen to your recommendations/ instructions about the interior wiring and I used something higher-quality (in my opinion) than the simple copper strands after all. And thank you again for your valuable help and your nice email correspondence.
P.S.: I am still blown away by my listening session yesterday evening. The Duettas keep getting better. On that K2 sampler, track 8, Heart of Glass, that I like so much... to be honest, I never heard the recording sound so authentic and intense, almost private, on the Reference 2. And the piano finally sounds like a piano. It’s just awesome.
Best wishes from Switzerland,