Brand-name Nagra belongs to Nagra Kudelski Group. As you surely realize Kudelski is a Polish name – the founder and chief engineer for many years is a Polish engineer. A story of his ancestors is also quite interesting. As you may read at http://stanislawow.net, Tadeusz Kudelski, father of Stefan – the founder of Nagra, was himself a son of Tomasz Kudelski, a Lvov Polytechnics graduate responsible for introducing to Stanisławow's architecture an art nouveau style. He started his job there with preparing a design of a building for Polish State Railways. During that job he simply fall in love with the city and settled in. His family ran an „open house” and among frequent visitors there were people like Stanisław Przybyszewski and Jan Kasprowicz – famous Polish poets but at the time teachers in one of the high-schools in Stanislawow. Tadeusz Kudelski followed his father's footsteps and attended Lvov Polytechnics as well. In 1918 he took active part in town's defense being one of the Lvov Eagles and an adjutant of his professor from Polytechnics, Kazimierz Bartel (a politician, three times prime minister of Polish government). This was a beginning of his carrier as Bartel talked the ambitious engineer to move to Warsaw and helped him to start over in the capitol. Even though Kudelski family were already residents in Warsaw they still came to visit Stanislawow quite often. It was there in so called „cooling room” which was in fact a basement, where young Stefan started his first experiments. There he said also to his friend that one day he would be a minister without portfolio – ambitious plans …

Nobody could have guessed then that one of the hi-end and professional audio legend had been just born. One of the key factors that contributed to that was how the history went – I mean surely in any circumstances Stefan Kudelski would have become someone special because he would have got it out of his family, but also other factors had taken part in shaping his company to what it became. By the way name of the company: „Nagra” comes from a Polish word „nagrywać” („to record” music for example). After lost September Campaign (Nazi attack on Poland in 1939) Kudelski family flied Poland together with Polish government first to Romania then to Hungary and finally to France. Stefan's father, Tadeusz, became a member of the Resistance and sent his wife and son to Switzerland. Stefan graduated from a high-school in French Florimont and after that he attended Polytechnics in Lausanne. He was quite disappointed with poor quality of the education he was receiving there so he decided to quit during the fourth year. After that in his small apartment in Prilly he designed and built his first tape-recorder. Years later he would receive a honoris causa degree awarded by the very same Polytechnics he attended in recognition of his work as designer of the Nagra tape-recorders. Tadeusz Olszański, author of an article about Stefan Kudelski and also his friend, wrote that Stefan sold his first tape-recorder for 1000 CHF and it became a great hit instantly. According to him the company was built without any bank loans – simply whatever was earned would be reinvested. Couple of years later Stefan Kudelski received first Academy Award (Oscar) for OST from Orfeu Negro (directed by Marcel Camus, 1959) that was recorded using a tape-recorder designed by him. Later his devices became standard recorders used by NASA. Stefan Kudelski was also included in the list of 100 most ingenious Swiss („Gent Suisses, 1998). So yes – he is a legend, and a part of a Polish history. It is a great shame that he couldn't take a bigger part in our history instead of Swiss one.

Nagra Kudelski Group is ran nowadays by Stefan's son – Andrzej and it is divided in two main parts – "Nagravision” and „Nagraaudio” – the latter is further divided into professional and hi-end divisions. MSA amplifier represents hi-end. Its symbol comes from „MOSFET Stereo Amplifier”. The direct predecessor was famous „pyramid” PSA, and I also had a chance to review both versions of it – stereo and monoblocks. These were very good sounding devices but I definitely didn't like their look - I mean the casing made of thin metal sheets was nothing like usual legendary mechanical design of NAGRA. I wrote about it then so there is no reason not to mention it now. In my opinion MSA's design corrects this previous „mistake” adding also some new ideas to it. It is still a tiny device that shares common casing with CDC player, PL-P, PL-L preamplifiers and VPS phonostage. MSA is a really tine piece of equipment but its ingenious, solid casing shows it's not a toy, or maybe it is a toy but for grown-up boys. Front and back panels are classic aluminum plates with characteristic for Nagra designs modulometer style power meter at the front. Side walls are made of aluminum sheets. Top cover is also ingenious – its a is one big heat sink, bigger then ever before. The aluminum slab they make this heat sink of weights 10kg and when its done it's only 3,5kg left. Amplifier offers 60 W output power at 8 Ω so in fact the casing doesn't get too warm. There are MOSFET – a pair for each channel – working in output stage. As you can read in Nagra's leaflet – this is an optimal setup that allows to eliminate mismatch of elements coupled in parallel.

So far we tested following NEGRA items:

• Linear preamplifier/phonostage/headphone amp PL-P HERE i HERE
• CD player/CDC preamplifier + amplifier PSA HERE
• D/A converter + amplifier MPA HERE
• D/A converter HERE

ODSŁUCH

Do testu użyłem następujących płyt:

• For the Masses, 1500 Records, 540 919-2, HQCD.
• Charlie Haden, The Private Collection, Naim, NAIMCD 108, 2 x CD; recenzja HERE.
• Chet Baker, Chet Baker Sings and Plays, Pacific Jazz/EMI Music Japan, TOCJ-90028, HQCD.
• Depeche Mode, Abroken Frame, Mute, DMCD2, Collectors Edition, SACD/CD+DVD; recenzja HERE.
• Diorama, A Different Life, Accesion Records, A 102, CD.
• Frank Sinatra, Sinatra Sings Great Songs from Great Britain, Universal Music/Sinatra Society of Japan, UICY-94421, SHM-CD.
• Garry Mulligan, Night Lights, Philips/Rainbow CD, PHCE-3064, CD.
• Joe Pass, For Django, Pacific Jazz/EMI Music Japan, TOCJ-90027, HQCD.
• Johann Sebastian Bach, Goldberg Variations, Matthews Halls, Linn Records, CKD 356, 2 x HDCD.
• Milt Jackson Quartet, Milt Jackson Quartet, Prestige/JVC, VICJ-41534, K2 CD.
• Voo Voo, XX, Sony&BMG, 520034 9, CD.
• Wolfgang Amadeus Mozart, Symphonies, Scottish Chamber Orchestra, Linn Records, CKD 350, 2 x SACD/HDCD.

When I first saw this little Nagra amplifier during unpacking and I put it on the vibration free support I was so impressed that I almost fell off the chair. I mean I would have had fallen off if I would have sat on one and not in my favorite couch. Even when packing Nagra back to the box – small box that could fit couple of beers at most – I was still full of admiration and jealousy. MSA (but always together with VFS!!!) is not only about the sound but also about the look. It is a fine example of how great could audio device look like being at the same time so small. This new Nagra's amplifier is a tiny piece of equipment, not much bigger than power module in my former preamplifier Leben RS-28CX. And this finishing! Swiss products are said to offer high quality. Even though stereotypes are often harmful if somebody wanted to prove this thesis, MSA would make a perfect example. And this vibration free support… It's been designed for tube phonostage but we all know that solid-state devices require well-thought-out mechanical design for vibration control too. I didn't test the support itself – just used it under Nagra during all listening sessions. Testing it separately would be quite difficult because the setup in my SolidBase VI Custom rack was time-consuming. To use it you have to screw three spikes (with their tips made of Derlin resin) to the bottom of the unit you want to put on the support. If you check it out how MSA looks like with its own feet and compare it to its look on VFS you will know – these two are a whole that shouldn't be separated.

So the look, size, proportions and quality finish are shockingly good. Aesthetically it doesn't have to suit everybody's taste as it does suit mine. Same goes for the sound. Although Nagra's amplifier is extremely competent when it comes to sound reproduction, all the details are well-thought-out but it still bears some sonic signature of its designer. I believe I managed to read designer's intentions quite well. In my opinion the main was to make it sound as alike 300B amp as possible. How would I know that? Nagra replaced directly Trafomatic Audio Experience Two - an 300B amplifier in my rack. Besides it is commonly known that Nagra is working on creating new push-pull 300B amp and they will use almost identical chassis as for MSA (just without radiator). But the most important clue was the same tonal balance and some other characteristic aspects of sound that put Nagra in almost the same spot as Trafomatic and other 300B designs. It's not an easy thing to do, very difficult in fact but obviously doable. That on the other hand introduces some limitations but I will deal with them later as an evaluation in absolute terms is one thing and potential buyer's preferences are the other.

Sound of this amp is bit on the warm side. During the same period I tested also ASR Emitter I and I loved it even though it was even warmer than Nagra. The latter „sugars” the sound and focuses on the first plan more like already mentioned Experience Two than like Emitter I (or Emitter II for that matter – please have a look on the test HERE). This last one offers so sweet sound that it almost crossed the line at which point it would have become unacceptable, too warm (and I didn't hold it against this amp, as some people would fall in love with its sound – I just wanted to show you the bigger picture). Nagra offers more distinct sound, doesn't pure liquid sugar on everything covering musical events with something else. And even though first impression will always be „a warm sound”, never „cold”. Why? It seems that the reason lays with slight rounding of transient attack. I heard same thing when reviewing PSA „pyramids” in both stereo version (reviewed for „High Fidelity”) and monoblocks reviewed for „Audio”. Even the biggest Nagra amp of the line – MPA – sounded in a similar way. That gives us a reason to come up with theses concerning „Nagra's sound” - sonic signature characteristic for all their products. And most likely we won't be wrong.

I described the sound of Nagra as a bit warm couple of times (I meant kind of warm timbres) but it didn't mean the it pushed the sound too forward, or did „boost” solo instruments or vocals. It was clear to me when I listened to some jazz recordings. Neither saxophones on Gerry Mulligan's Night Lights, nor guitar on Joe Pass'es Joe Pass for Django, nor finally Frank Sinatra's vocal on Sinatra Sings Great Songs from Great Britain that are usually presented in front of loudspeakers, were pushed that far this time. It is simply not this kind of „warmth”. That also brought to mind comparison with 300B amplifiers– these properly designed don't have to use such forward presentation because great resolution and incredible energy coming from simplicity of such designs urge our attention to focus on instruments, vocals and so on. Nagra does it in a very similar way – instruments attract attention because of their beautiful timbre, fantastic microdynamics and outstanding resolution.

This amplifier sounds, to be short, „nice” but not too pretty so to speak. The device preserves most of an original instruments timbre – maybe not so ultra-precisely as Trafomatic does, and differently from what I know so well from my own Luxman M-800A. Nagra isn't also a master of space and ambiance presentation and can't differentiate as well as the above mentioned amplifiers. But it looks like it wasn't an idea of its designers. They wanted to present as good timbre as possible preserving sound's focus. And it worked in 100%. There are some elements that 300B amp, even the best one, can't do with „classic” loudspeakers. First that comes to mind is bass. Nagra offers lower range strong, extended with a bit warm timbre. Although at the very low end bass is not that well controlled as by my Luxman it is still considerably good. And up the scale bass becomes very good. Thus Nagra was able to present in a fabulous way both – strong bass from Voo Voo's XX, but also Joe Passes guitar.

In the upper part of frequency range where you can hear cymbals or vibraphone – the latter for example on Milt Jackson Quartet – it seems that this range is slightly laid back, bit darker. But I'm not 100% sure of that because some high-quality recordings like Haden's The Private Collection, especially the second disc with concert from Webster University in St. Louis, didn't sound laid back at all. To put all that somehow together I listened to couple of recordings paying special attention to the tape's noise. Of course nobody listens to the background noise but to the music, but the noise from mother-tape introduced to the recording by for example microphones is a very handy tool – when you listen to a white noise carefully once you can use that to compare different recording later. Nagra limited this back-ground noise a little. That meant that the upper range was to some extent modified by it. It was not a selective action but rather slight slope of the whole range which makes it unnoticeable when listening to high quality recordings. You don't have an impression of a dark somehow „limited” sound because the midrange as a whole is very open and strong. It is worth focusing for a moment on this part of the range as it introduces some limitations. Although Nagra offers output power of 60 W at 8 Ω, but it is not able to drive loudspeakers as well as my also 60W Luxman. This element proves that tiny size of MSA matters. At the high volume levels with Nagra you can hear some compression in sound – like with Wojtek Waglewski voice on XX. This a great recording of instruments and a very poor one of a vocal most likely because of the compression. Warm sounding amplifiers are able to cover that up a little because they average the sound in all recordings, but Nagra is not a classic „warm” amp and it presents such weaknesses of recordings precisely. So if we turn up the volume Nagra will emphasize this flaw. Most likely it will not be a big problem because it didn't happen in 30 sqm room at „standard” volume levels. But if you have a larger room and difficult to drive loudspeakers you better think about getting two MSAs working employed as monoblocks.

MSA without preamp

All written above concerns a set of MSA paired with my Ayon Polaris II preamplifier with AC-Regenerator power supply. Nagra offers also a CDC player with preamp integrated – so you can always try how does it sound – amp + CD player and that gives you a chance to save quite some money. By coincident my own new player – Lektor (most likely it will be called Air) also has an amplifier integrated in it. For me it was obvious that I was going to try Nagra in amp-CD configuration. Removing this amazing, costing over 50 t PLN, Ayon's preamplifier from the system changed surprisingly little in the sound. Of course there were some changes but so little that comparing value of both systems these changes could be treated as irrelevant. A scale of the sound grew smaller by a tiny margin but it did. The front layer of the sound wasn't so palpable anymore, bass wasn't that energetic and less extended. But there was also something that improved – depth of the soundstage, it had been good before but now became very good. Transparency and resolution of the sound were similar (bravo for Ayon). I was really impressed by so small extent of changes. I believe that using some more distinct sounding preamplifier – maybe Nagra's PL-P – could effect in more changes in sound delivered by preamplifier. But for sure one can use a combination of Nagra's amp with CD player with integrated preamplifier like own Nagra's or Ancient Audio and then later thing about adding some preamp.

Summary

It is a really interesting device. With kind of warm sound but not too warm, tiny but offering a big sound, solid-state but sounding bit like a tube device. What's important is his amplifier is not a mixture of some ideas – one can tell that all that has its purpose and was intended by its designers. Each of these features work in conjunction with others. That's why MSA is an amplifier with clear purpose, and that's also why listening to it is so pleasant. Unlike with other warm sounding amps this one might not be the favorite device for people listening to electronic music. I think that Nagra's care for each sound and tone is what takes away some dynamics, shrillness that is essential for music like Diorama's. Depeche Mode records, also the older ones like Abroken Frame sounded better, but the tangibility of sound could be better. Jazz and classic music sounded with Nagra remarkable – if you have a chance listen for example new Linn Records releases like: Wolfgang Amadeus Mozart Symphonies or fantastic J.S. Bach Goldberg Variations, with Matthews Halls playing harpsichord. Brilliant piece of craft, great look, brand-name, remarkable sound although especially with small ensembles. You will find it hard to resist this tiny Swiss beauty…

DESCRIPTION

MSA is a stereo amplifier. Its ingenious form combines Swiss precision with a tiny size. The casing is made of aluminum – front and side panels are aluminum slabs and the top cover is one big heat sink. There is a famous Nagra modulometer style power meter and a „Power on” selector in the front pannel. You can choose between „off”, „standby”, „auto” (it will come on when signal is detected in the input), „mute” and „on”. Backpanel includes two pairs of nice, gold-plated WBT 0763 speaker posts and a pair of XLR inputs. Yes, there is only one balanced input – the device is fully balanced. You can always use RCA-XLR Neutrik's adapters that are delivered with the amp. A bridge selector switch on the rear panel allows parallel bridging, and the MSA will then double the current at the output as well as the power. There is a small toggle switch that allows to change between „Bridge”, „Normal” and „Bi-Amp” modes. The last one can be used if you want to use MSA for bi-amping. There are also two other small toggle-switches that allow us to change input sensitivity – you can choose between 1 and 2 V. There is also IEC socket and mechanical on/off switch in the lower corner.

It was possible to put this amp in such a small casing thanks to an innovative power supply module. Although the main element is large toroidal transformer shielded and placed on separate support, the two, one per channel, control chipsets are also key elements. There is a specialized Linear Technology LT1248 (Power Factor Controller) chip controlling the whole power supply. It is a part of PFC (Power Factor Corrector) setup introduced for the first time in MPA amplifier in 2000. This setup is placed between transformer and the powered circuit which helps to generate correct sine curve. So it is in fact a kind of power conditioner. That's why we get here more elements of surface assembly and only two mid-size filtering capacitors. And in this section you can find all inductive elements – as you can see on the picture – coils with cores and lot of large polypropylene Wima's capacitors. Amplifying circuit is amazingly simple with short signal path. It is based on transistors with pair of MOSFETs per channel, operating in AB class. All PCBs look very good and the paths on them are gold-plated. Signal gets from the input to small shielded PCB, with input socket soldered directly to it. You can tell that input sensitivity is set via resistors bridge here.

The device uses something I wouldn't even call „feet” - just four plastic discs. Nagra simply encourages users to experiments with different feet, spikes and so on. That explains presence of four drilled wholes that can be used to install for example Ceraballs from finite elemente. In my opinion it is much more reasonable to purchase Nagra's VFS (Vibration free support). Designed particularly for their phonostage it worked also very well with PL-P linear preamplifier and now also with MSA amp. It is so universal because all these devices have the same basic size. Support is made of two 7mm thick solid aluminum plates, with little feet made from alpha-GEL between them. It's different colors for each plate were respectively chosen to eliminate different vibration ranges giving optimal vertical and horizontal distribution of the absorption. The VFS is delivered with three spikes or feet, which are screwed to the bottom of the unit to be placed on the VFS plates. Machined from ARCAp, a completely non-magnetic copper-nickel-zinc non-ferrous alloy with their tips made of Delrin resin they make a support look really cool!

Technical data (according to manufacturer):
Power: 2 x 60 W rms/8 Ω („normal” mode selected)
Input sensitivity: 1 or 2 V (selectable)
Bandwidth: (+0/-3 dB): 10 Hz-70 kHz
S/N: 104 dB
THD+N: < 0,09 %/100 W
Size: 280 x 230 x 118 mm
Weight: 9,6 kg