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ENRICO ROSSI ⸜ Norma Audio Electronics

Via Persico 26, Frazione Bettenesco
26043 Persico Dosimo, Cremona ⸜ ITALY


When: 5.04.2024
Where: KRAKÓW, Poland


Images by „High Fidelity”, Marek Michalczyk

No 240

May 1, 2024

Norma Audio Electronics is an Italian company founded in 1987. Initially specializing in amplifiers, with its first product being the NS 123 integrated amplifier, it was bought by Opal Electronics in 1991. It took nearly seven years of research and development to come up with an entirely new series of devices, many of which are still offered today. We speak with Mr. ENRICO ROSSI, the company's chief engineer.

ONE OF THE "DEADLY SINS" of the music industry, as cited by Steve Knopper, author of Appetite for Self-Destruction: The Spectacular Crash of the Record Industry in the Digital Age (2009), was overlooking the revolution that Napster heralded. The application, written by 19-year-old students Shawn Fanning and Sean Parker, premiered in June 1999 and momentarily gained immense popularity, at first mainly among students. It allowed free exchange of mp3 music files between users' computers.

Record labels, above all the so-called "majors", i.e. the largest ones, frightened by the loss of earnings, did their best to end this enterprise, instead of absorbing this solution. As it soon turned out - the solution of the future. Today, a quarter of a century later, we know well that this was the logic of history, and that on this decision, that is, defending the physical Compact Disc format, the publishing industry lost huge money. The thing is, this change was not about sound quality, but about access to music - users raised on illegal or semi-legal software wanted music FOR FREE.

Twenty-five years later, we notice something strange - in addition to the renaissance of the LP, driven largely by popular culture, the CD is also returning to favor. This is interesting, because it is not on even 1/10 as "sexy" as the LP disc. Small, usually in a bland plastic box, it doesn't have the impact of a 12" black disc cover. And yet...

⸜ Enrico Rossi draws the layout of a typical audio circuit, showing where the signal is converted to unbalanced and vice versa

This trend has also been noticed by manufacturers, investing a lot of money in this format, both in terms of mechanics and electronics. One such company is the Italian company Norma, based in Cremona, home of the greatest Italian luthiers of all time. Four years ago, it launched a project that resulted in the CDP-2 player, a test of which you'll find in the same issue of High Fidelity, and which is also featured on our April cover. The work focused on an innovative D/A converter of their own idea, which was called A-DAC.

As it turned out, the company's head of engineering, ENRICO ROSSI, is familiar with my tests and, I repeat after him, respects my approach to them. So he wanted to take the opportunity of testing the CDP-2 in my system and arranged an interview with me. He flew to Krakow for two days together with ALBERTO BARONI, head of the company's sales and PR department.

Alberto, we might add, is also an independent filmmaker. As we read on his website, he creates documentaries, web videos and commercials, working as a director, cinematographer, editor and post-production manager. He works for the CTU (University Television Department) at the University of Milan, taking part in the creation of documentaries and spots for the university. In 2015, he made his first short film Impero (Empire). Since 2018, he has been writing for the online film magazine Gli Spietati; more: →

Although we were supposed to fit our meeting in two hours, then go to dinner at a restaurant of my choice in Plac Nowy in Kazimierz, things got out of hand and four hours later the gentlemen had to get going quickly, as they had tickets purchased for an evening concert at the Krakow Philharmonic. And even so, I feel, we didn't talk about everything we wanted to. We did, however, manage to talk about the new player, our plans for the future, exchange experiences about the CD, and listen to the CDP-2 together in the "High Fidelity" reference system; it is from this part that almost all the photos in the article are taken.

During the interview, we swapped roles for a while and it was Enrico and Albert who questioned me about various things, clearly interested in my opinion. You will find some of these questions and my answers below.

ENRICO ROSSI, chief engineer of Norma Audio Electronics, with ERTO BARONI, head of sales and PR, is interviewed by WOJCIECH PACUŁA.


WOJCIECH PACUŁA Judging from the technical materials, from the fact that you are with me today in Krakow, one can guess that the new CDP-2 player is very important to you (all emphasis - ed). At its heart is a D/A converter called A-DAC - what does "A" stand for?
ENRICO ROSSI "A" stands for "analog". We developed this new converter, with the emphasis on "analog," for two reasons. The first was simply for the sound - I wanted to develop a device whose sound would be as faithful a reflection of natural, or analog, sound as possible. The second reason was to change the approach to conversions offered by off-the-shelf D/A chips. Inside the black box, which you can see inside the device, we placed a really complex, elaborate analog circuit.

⸜ Enrico Rossi with yours truly in front of the „High Fidelity” reference system

WP Does it mean there is no DSP there?
ER Obviously, there is also DSP chip there, but in reality it is a mix of digital and analog circuitry.

WP This type of system is a complex problem - when did you start working on it?
ERWork on it began when COVID hit, and it took us a full four years to refine it./p>

WP What was your reference?
For many years we have used Burr-Brown PCM1704 converters in our digital equipment. It's a classic and, for me, it's the best chip available on the market It's not perfect, but it has the most balanced sound of any I know. It's also the chip with the most "analog", and the most natural sound. I've tested all the D/A chips available on the market, and none even came close to it in terms of the sound I was after.

WP PCM1704 required an external digital filter, the DF1704, does your A-DAC also feature a filter of this type?
ER In the past, we have used the high-end DF1706 digital filter in "Slow Mode." And that's because "Sharp Mode", or fast mode, is more linear, but its sound is more aggressive, not so pleasant. Slow filters sound more natural, especially when it comes to the soundstage, the sound of acoustic instruments, etc. The A-DAC circuit also has a digital filter, the equivalent of the DF1706 in "Slow mode". When you look at its impulse response you will see that there is no oscillation before and after the signal on the graph.

WP Why is the whole circuit locked in a "box"? - Is it about protecting intellectual rights or something else?
ER The main reason for enclosing the whole thing in an additional box is the need to equalize and control the temperature - the analog section is extremely sensitive to its changes. So we flooded the DAC circuit with epoxy resin and enclosed the whole thing in this small "box". This ensures that the temperature is not only controlled, but is the same at every point in the circuit, and this is critical for its proper functioning.

WP Was it the same thing with the I/U conversion circuit? - I ask because it too is located in the black "box".
ER Exactly, it was about temperature control. Usually temperature drift problems are overlooked at this stage, and this is, in my opinion, a mistake. Here, too, the unification of its value at each point of the system is extremely important for its proper operation.

WP Just behind the I/U section you can see a single Burr-Brown operating chip, but it looks like there should be another "box" there - you can see the mounting screw holes.
ER Yes, this is the space for another "box". It is supposed to house the circuit that controls the XLR output. More specifically, the I/U and amplifier for the negative branch of the signal. In the standard version of this player, it is amplified in this IC in question. In turn, the positive branch comes out of the "black box" in front of it. But as an option, in the Reference version, it is possible to mount more "boxes", which will give a mirror balanced circuit. Now it's also for symmetrical, but, as I say, one branch is converted and amplified in the operating circuit. The reason for this configuration is our belief that the best link is an unbalanced link, i.e. on RCA jacks - and this is what we focused on.

WP It’s interesting because that’s what I’ve been saying for years.
ER Yes, we know about it, we read the tests in High Fidelity, so it's all the easier for me to explain what it's all about. I can show you how we did it [at this point Mr. Enrico draws in my notebook, incidentally from Japan, the electrical circuit of the DCP-2].

The problem is that most manufacturers in their amplifiers at some point transition from balanced to unbalanced circuit to be able to change the volume, after which the signal is further amplified in unbalanced circuit. Also, almost all tube amplifiers operate in an unbalanced circuit. Many CD and file players also convert the balanced signal to unbalanced or unbalanced to balanced at some point, depending on the D/A circuit used.

We made the assumption that, except in the rare case of fully balanced amplifiers, i.e. with four independent amplifier paths (two per channel), the signal will be converted to unbalanced somewhere along the way - that's about 80% of the products on the market. Therefore, it is better to use an unbalanced link. The problem is that the outputs of almost all CD and file players are routed in a balanced path, and the RCA output is desymmetrized in them. This means that there is an additional circuit in the circuit, and this changes the sound. Considering that most amplifiers desymmetrize the XLR input signal anyway, this means that we have as many as two or even three additional stages in the CD → amplifier path, and they are almost always ICs. We decided that this is not a good way to achieve good sound.

There is also another reason why I prefer unbalanced connections - the vast majority of physical phenomena around us are asymmetrical in nature. Even the transducer in a loudspeaker works in an asymmetrical way. A balanced circuit is useful in the recording studio and on stage, where it's all about protection from interference and where sound quality comes second.

WP Let's summarize: the A-DAC is a circuit with unbalanced output, do I understand it correctly?
ER Yes, it is an unbalanced circuit. Like the PCM1704 it outputs an unbalanced current signal. So the I/U circuit is easier to make precisely, and we don't need to use a symmetrizer or desymmetrizer. This is the simplest circuit that could be made. And this is very important.

And that's another reason why we developed our own D/A circuit. I guess all converter chips available today have balanced output, and we - for the reasons I mentioned - needed a circuit with unbalanced output. Balanced/unbalanced conversion takes a lot of information out of the music, mainly in terms of timing.

WP We talked about electronics, let me ask now about mechanics.
ER This is a transport mechanism made by TEAC. The problem is that the TEAC company has announced that it is ending production of transports, at least of this type. The brand has been sold to various entities, each division to a different company. The group that bought the audio part is not interested in producing CD players. Therefore, we bought a huge number of these drives, thus securing production for many, many years ahead.

WP I'm a big fan of the CD format, so this is very sad news for me. Somewhat confirming the continued shallowness of the electronics-related world - now it's all about producing as many things as possible at the lowest possible cost. Complex products don’t fit into this business model.
ER We also love CD. I'm a huge LP fan, analog tape is magical in my opinion, but it's the CD that gives me the most joy. By the way, tell me what you think about streaming?

WP Streaming is a fantastic invention. Almost for free, it gives us access to music that we wouldn't hear any other way. It's the reality we live in and will live in. But for me it's more like the equivalent of radio, which is how I use Tidal. If it's a matter of finding something quickly, of accessing news, then the advantages of this type of music distribution are undeniable. But... Once I find something I'm interested in, if I like it, then I often buy it on CD and then that's my target format.

I've been working with digital devices almost since the beginning, I've been in contact with exactly all formats of this type, from CD, DAT, CD-R/RW, Mini Disc, DCC (Digital Compact Cassette - ed.), DAW computer systems, and I must say that the sound quality obtained from them is now much, much better than what I had to deal with in the beginning, and especially when it comes to files. With that said, no one in the audio industry has been talking about mp3s for a long time now, as high-resolution files are the norm.

But, in my opinion, there is still a problem with file playback. By themselves, in my opinion, they are meaning-neutral, that is, it is not in the files themselves that the problem is - after all, almost all CDs that come out nowadays were prepared from files, right? The problem arises only when we want to play them. And here is something that I don't think we fully understand, which makes me always choose CDs over streaming.

There are many problems with streaming, by the way, and one of them is different mastering for each platform, as Kraków-based mastering artist Paweł "Bemol" Ładniak once told us, who, by the way, mastered the files of Mettallika's latest album precisely for streaming services (more about Paweł → HERE - ed.).

ER Why is mastering for each platform different?
WP That's because each of them has different aggregation algorithms, a different system to collect files and give access to them. It turns out that this requires different levels of LUFS, that is, different compression, etc. The files we stream from different platforms are not the same files, they are different..

ER That means, that the file we are streaming is not exactly the same file that came out of the mastering studio?
WP If we consider the "master" file to be the one made by the mastering engineer with all other media in mind, from which files are then prepared for LP, CD or streaming, then - no, it's not the same file. And it's not at all about changing the bit depth or sampling rate. I know from experience that 16-bit recordings often sound better than 24-bit recordings (more in the article Mastering à la streamingHERE - ed.).

ALBERTO BARONI And what do you think of CD drives in file players for ripping CDs to a hard drive?
WP In my opinion, this does not make sense. I understand, sometimes it can be convenient to rip a CD and play it from a disk. But I would listen to a CD and not a copy of it for pleasure. In my opinion, it's already better to buy a high-resolution file and listen to it, not a CD rip.

ER I have a similar experience. Whenever I compare files and CDs, using the same DAC, for example in the DS-1, the CD sounds better to me. But during the pandemic, I had a streamer from Innuos at my place. And that was the first time that, in a direct comparison, a file ripped by that device from the built-in CD drive sounded better than CD itself - so we were curious about your opinion on CD ripping.

In my opinion, the biggest problem is signal transfer. Especially when it comes to the USB link. But not only that - I found that the critical moment is the transfer of files from the HDD over the eSATA link. This is an extremely sensitive link and the shorter the better. The already unpacked digital signal is best sent over an IIS link, but provided the cable is very short. Really very short. We tried such systems, where we had a separate CD transport and a separate DAC with an IIS input, and we found that signal transmission in this way is very sensitive to the quality of the connection cable and to its length. At this distance it was, in my opinion, a substandard connection. It is already better to use a USB cable.

In general, working with a digital signal is more difficult than with an analog signal. In a digital circuit, every component, even the smallest, changes the sound strongly. In analog, too, but the scale of changes we hear in digital systems is much greater. This is very strange, because intuitively we think that it is the analog signal that is more prone to distortion, and digital is digital - "ones" and "zeros". This is not true, and we have a lot of experience in this.

In our D/A converters, we did many trials with tiny component changes and the sound was different every time. There are a lot of components in a digital circuit that have a big impact on the final sound. And when measured, they look identical - as an engineer, I can't understand this, but I have to accept that this is the case, because you can just hear it.

| ENRICO ROSSI and „High Fidelity” reference system


⸜ Enrico Rossi brought many CD-Rs with him to Krakow, one he’s been using when developing and tuning Norma components

LET ME START WITH SAYING that for some time now I have been trying to force my mind not to make evaluations of audio systems I know nothing about. In your case, the only component I knew was the CD player. Everything else is unknown to me. Electronics, cables, speakers, environment, positioning, etc. etc. And, as we well know, each of these elements is very important and can significantly change the outcome of a listening experience.

But, I must say, I recognized the character of the Norma CD player in your system; it's a very "tangible" sound, with very good sound imaging and spatial placement of instruments. The dynamics and sense of presence in a musical event were also strong. I also enjoyed discovering, thanks to the Host, new music that I was not familiar with, and I will certainly be able to learn more about them thanks to the Qobuz service.

At first I was a little "destabilized" by the lack of "focus" of the sound images - this was the case when I was sitting in a position symmetrical to both speakers. When I moved to the place that Wojtek suggested to me from the beginning, the "focus" improved significantly. Only perhaps the geometry of spatial reconstruction suffered a bit, losing a bit of symmetry between the left and right sides. However, given that both speakers, due to their placement, have two very different acoustic environments, this deviation is acceptable.

I'm sure that Wojtek knows his system well enough that it is easy for him to understand the nature of the elements he changes in it. By the way, I would be very curious, and I'm already thinking about my next visit, to do a comparative listening between the Missa Criola release that the Host has on a Master CD-R from FIM Publishing, and the "standard" one. It's a beautiful recording that I've been using for years in the development of Norma products. ER

WP I THINK THIS IS A GOOD MOMENT to go back to the CD player we are talking about. There is a covered slot on the back for digital inputs. As I understand it, this is a separate module and it too is new?
ER Yes, this is a completely new module, we call it Mk II. We completely redesigned the earlier digital inputs because, as I said, we found that even small changes in such a place strongly affect the sound. Even the tiny ones. I think that by working on this problem we were able to prepare a really transparent input module. We tried it out by plugging it directly into the CD transport on one side and into the DAC on the other, as an additional component, and compared the sound to a system where the transport was connected directly to the DAC - we heard no difference. So we assume that the Mk II digital input module is sonically transparent.

However, it was a different job than usual. When we realized the importance of components in digital systems we had to switch from classical thinking about the digital domain to a new one. For example, in almost every DAC and CD player there is the ability to change the absolute phase. One button and you're done. But to do that you need to add one circuit in the signal path, a digital inverter. It turned out that this small element makes the sound worse.

You can check this for yourself by turning on the phase restoration and changing the connections in the speakers - you will then hear only this one additional element in the signal path, without changing the absolute phase. I assure "High Fidelity" readers that the difference between these presentations will be considerable. This small component is not at all transparent. "Digital" is very, very, very, very - here you can type any number of "very" - complicated and still poorly explored sphere of audio signal processing.

WP And here we agree :) There's something about the fact that early digital recording systems, whether Denon or Soundstream, left behind very good recordings. And yet these were not 24-bit recordings....
ER Ooo - Denon - these are, in my opinion, incredible realizations. Listening to them from LPs, records often recorded with 14-bit resolution, is a unique experience. They sound spectacular. The problem is CDs of the same material, which no longer sound so spectacular. Something got lost along the way....

Therefore, when people say that sixteen bits is not enough, that the CD standard is insufficient I say just listen to Denon's first recordings on LP, that is 13.5, then 15, and finally 16-bit. They do sound great!

WP I can't help but ask at this point, what then is your next project?
ER At the moment we are launching the "2" series devices: CDP-2 and DAC-2 in the Revo series. This is a big project for us, and we don't even know exactly what will be next. The problem is not products or projects, because we have several things ready and many ideas, the problem is people. There is simply a lack of skilled workers in Italy. This is our biggest concern. It's like in a restaurant, you can have the best menu in the world, great ingredients, invite people in, but if there's not someone to prepare it, it won't succeed.

But I'll show you the designs of new devices, for example, an amplifier. It's a big project that takes time to get to the point where we can start producing it.

Enrico takes a moment to look on his cell phone and displays a rendering of the new amplifier. I must say it looks great. And that's not all because the new CD players are supposed to look similar. All of them, I might add, have that distinctive top panel shape..

⸜ Finally, a short statement from the author of the interview about the CDP-2 player and the CD carrier

WP I really like the design of your products - did you hire an outside company to prepare it?
ER A man responsible for the design is Livio Cocozza, the same man who has been designing the look of Sonus faber speakers for years, today their chief designer. It's amazing, but he prepared them for us in 2005-2006, so a long time ago, and yet our devices still have a fresh and unique look. The first thing he designed for us back then was the Revo series.

WP While on the subject of new products, I'll also like to ask about such a thing: I found somewhere that the A-DAC used in CDP-2 is "Type 1". Does this mean that there will be others, such as "Type 2 or "Type 3"?
ER The layout of this DAC can be scaled, down or up. The version that is now in the CDP-2 is, one might say, the "standard" version. The next ones will be for higher-end devices. They will be much more complex. But, in my opinion, to find a CD player today with such an analog sound as the CDP-2 is very difficult, so this will be a big challenge for us.

WP Is it now a good time for your company?
ER (He smiles) Yes, it's a really good time for us. We have a lot of orders - maybe a tad too many for our capabilities - but it's a really good time. And, such is our understanding of the market situation that many people will return to CD format.

AB This is related to how important music is in our lives. In my generation, and I'm thirty-eight years old, CDs were a very important medium, I spent my youth with this format. When I was younger, I would sit down with CDs and listen to them for hours. Today things are a little different, and because of the ubiquity of music, its importance in people's lives is no longer so great. Young people are doing a lot of different things at the same time and are less focused on each activity individually. But, such is our hope, there will still be those who want to experience music in its best form, that is, with top sound.

WP Thank you very much for your visit and see you again!
ER We would also like to thank you and cheers to all „High Fidelity” readers!


SEVERAL DAYS AFTER Enrico and Alberto's visit, it was already clear that one of the two STATEMENT in High Fidelity 2024 German Edition awards will go to the Norma Revo CDP-2 Compact Disc Player - hearty congratulations! The award will be presented at the Munich High End Show 2024. As always, we will report on it to you; info on previous awards → HERE and → HERE.