⌈ 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 are testing the REVO DAC-2 with a proprietary D/A conversion circuit called A-DAC. ⌋

ONE THING THAT SEEMED to be a passing trend, but which will stay with us for a long time, at least that's how it looks, are Compact Discs autographed by performers. I'm talking not about getting them after concerts, in front of hotels or, deep into the night, in a bar with the signatures of beloved artists, but about the sales strategy adopted a few years ago by some publishers.

These, in addition to regular releases, whether CDs or LPs, offered signed discs. Most often in separate menu tabs, described as “Exclusive Signed Versions” (Deutsche Grammophon), simply “Signed” (Decca) or “Signed Art Cart” if additional art-prints rather than covers are signed (Blue Note Records); in Polish terms, it's usually “Autographed CD” (Luxtorpeda store, Kayax) or simply “With Autograph” (Polskie Nagrania).

These can't be large print runs, artists are people too, and also signing everything as it flies makes these no longer exclusive versions. And yet publishers seem to be paying more and more attention to it. Why? Perhaps, I would love it if they did, they realized that the real money lies in physical products. Streaming, an excellent invention that democratizes access to music, leads to the impoverishment of both artists and the publishers themselves. And, as a result, to a less diverse market and a deterioration in the quality of recordings.

A similar “awakening” can also be seen on the side of audio manufacturers. Although some ten years ago many of them told me about the “death of the format”, nothing of the sort has happened. Today, more and more often, one hears about the release of new Compact Disc and Super Audio CD players, to mention, for example, the companies such as Wadax, Bricasti Design, Esoteric, TEAC, dCS, Luxman, Accuphase, Simaudio, Exposure, Cyrus, Auralic, Cambridge Audio, Arcam, Roksan, NuPrime, Musical Fidelity, Pro-Ject, not forgetting Denon and Marantz, brands that “moved” the SACD format above the “dark valley” of doubt in the 2010s.

Even Vitus Audio, whose owner a few years ago swore to me in all holiness that he would “never touch CD mechanics again,” in 2023 offered the MP-T201 Mk II CD transport in its Masterpiece reference series. The group of “supporters” of this format, if I may say so, also includes the Italian company Norma Audio Electronics and its designer, Mr. Enrico Rossi; let me refer those interested in his person and company to the interview he gave to our magazine → HERE.

▌ Revo DAC-2

THE DAC-2 DIGITAL-ANALOG CONVERTER, part of the Revo (Revo-lution?) series, is solid and very well made. It measures 75 x 430 x 350 mm and weighs 10 kg. It offers five digital inputs, USB, two RCA, optical Toslink and AES/EBU. Its electronics circuits are unbalanced, but we can send the signal out either through XLR or RCA jacks. It is worth noting, when making comparisons, the output voltage – it is 3 V for RCA and 6 V for XLR, so it is as much as 50% higher than the standard for CD players (2 V). The set comes with a remote control.

This is a classic DAC, without Bluetooth and output voltage (volume) control. It is a “derivative” product. In the sense that its electronic circuitry was largely developed for another device, the Compact Disc player. The CDP-2 model, which had its world premiere in our magazine, was publicly unveiled at the High End 2024 show in Munich; more → HERE. It was based on a TEAC transport, also found from time to time in devices from other manufacturers.

The owner of Norma, Mr. Enrico Rossi, who flew to Krakow at the time to talk about the CDP-2 and to listen to how the device performs in my reference system, spoke of four years spent on the design and its implementation into production. And he was referring to the electronic part rather than the mechanical part. For the star of the evening was the DAC. The same DAC can be found in the reviewed device. It is a completely proprietary circuit, from the D/A circuit itself, to the I/U conversion, to the output circuitry.

THE LOOKS • The DAC-2 belongs to the Revo series. Initially treated as “premium” by the manufacturer, it is becoming, as I see it, the basic series. It now includes a line preamplifier, two power amplifiers, two integrated amplifiers, two CD players and, the subject of this test, a DAC.

The appearance of all devices in the series share common features, so within it they are similar. So the DAC-2 looks like the CDT-2, minus the drawer and with the display moved higher up. Its chassis is made of thick aluminum sheets, and the front is milled from a piece of the same material. The top and bottom panels are not rectangular or square, but converge towards the back. The units are offered in a silver aluminum finish, but for an extra charge we can also order a version in black anode. The silver DAC-2 costs PLN 19,990, and for the black version we will pay an additional PLN 1390.

Since there is no disc transport in the DAC, it was possible to move the display to the center of the front panel; in the CD it is below the mechanics. It is large and easy to read and, like in the EMM Labs devices of the past, is blue in color. So it's a good thing that – on request - you can order a device with a display in red or green; there is no possibility for the user to change the color in an already purchased product.

It reads the number of the selected input and the sampling frequency. One of the dots between the digit segments tells us about the publisher's use of pre-emphasis for a given CD. Recall that pre-emphasis was a noise reduction technique used on early CDs. This system amplified the highs on a CD, and the CD player lowered them back to normal levels. The equalization curve at 20 kHz had a -10 dB drop. This technique resembled the operation of RIAA equalization on LPs, and to some extent the Dolby system, although without its negative effects.

There are also metal silver buttons on the front panel. The left one turns the unit on, and the right ones allow user to navigate the menu and select an active input. Their markings can be a bit confusing, as they are similar to those on the preamplifier in this series, there are – for example – buttons for the volume adjustment.

FEATURES • The Norma DAC-2 offers five digital inputs, the “widest” (in terms of supported resolution) of which is USB. It accepts PCM signals up to 24 bits, 384 kHz and DSD up to DSD512. The other inputs are for PCM signals up to 24 bits, 192 kHz. There is also an option of sending a digital signal out – the BNC jack (#5) is used for this purpose. In the menu, we choose whether this is to be an input or an output. The DAC-2 can thus work as a digital signal converter, converting the signal from RCA, AES/EBU or optical inputs into a 75 ohm electrical signal.

The device offers quite extensive functionality. It allows you to select the clock mode - synchronous or asynchronous – absolute phase, channel swapping for DSD signals (!), and to mute the output signal when changing the inputs or sampling frequency of the input signal. Changing the word clock mode allows you to choose between its synchronization with the clock signal transmitted with the audio signal from the source, or its asynchronous, i.e. independent, clocking. The manual reads:

The user can select the clock mode for the PCM format and for the DSD format, respectively. The clock can be “direct” (Dir), which is the same as the input source; or asynchronous (Asyn) - in the latter case, it is re-clocked in the Digital Audio InterFace chip. We recommend using the “Dir” setting, but in some cases it may be better to re-clock the signal and use the “Asyn” mode. We recommend performing listening tests to choose the best solution. (s. 13)

Channel swapping for a DSD signal is a solution that is rarely used, but it may happen that a DSD signal, if it is digitally converted somewhere along the way, has swapped channels. In the case of the DAC-2, this function is active only for the USB input. Much more interesting, however, seems to be the possibility to bypass the relay, which is placed on the line output of the device. Its presence is a standard solution, as it knocks down the “cracks” that sometimes appear when we switch inputs or change the sampling frequency of the input signal.

It does not always happen, but with some combinations of source → DAC it does. This is prevented by the aforementioned relay, for a fraction of a second turning off the output. But, like any component in the circuit, it brings something extra from itself, it is not electrically “transparent”, no matter what class it is and how much attention has been paid to its implementation. So Norma proposes a mode in which it is excluded from the circuit (shorted), and it is the user who chooses which mode to use.

The set comes with the RC-31CD remote control, similar to the RC-41 that comes with the company's IPA-80 amplifier. Made of aluminum, it has well-functioning buttons with a clear point of operation. The remote supports both Norma amplifiers and digital players, but this model is primarily geared toward CDs.

The spacing of the buttons and the priority assigned to the amplifier's buttons makes it not very convenient to use. And it is offered in only one color, silver. It would be logical if, along with changing the color of the chassis, the color of the remote control itself would also change.

DAC-2 is a competently built device. We can find many proprietary solutions in it. You can also see the desire to keep the signal path as simple and short as possible, but with good functionality.

▌ SOUND

HOW WE LISTENED • The Norma Revo DAC-2 was tested in the HIGH FIDELITY reference system. It stood on the top carbon shelf of a Finite Elemente Pagode Edition Mk II rack on its feet. Its sound was compared to the AYON AUDIO CD-35 HF EDITION SACD player and the Lumin T3 file player.

The signal to the DAC was sent via USB input from a Lumin file player, and to the RCA input from an Ayon Audio CD player. The cables were, respectively: USB-1.0PL Triple-C and Acrolink Mexcel 7N- DA6100 III. The DAC-2 was connected to the Ayon Audio Spheris III preamplifier with unbalanced cables Crystal Cable Absolute Dream. Power to the DAC was supplied by Harmonix X-DC350M2R Improved-Version cable.

» RECORDINGS USED IN THE TEST ⸜ a selection

⸜ MAYO NAKANO PIANO TRIO, Miwaku, Briphonic BRPN-7007GL, Extreme Hard Glass CD-R (2017).
⸜ MILTON NASCIMENTO, Courage, CTI Records | A&M Records/Universal Music Company UCCU-6284, „All Of Jazz” (1969/2023).
⸜ LEONARD COHEN, Popular Problems, Sony Music Labels SICP-4329, CD (2014).
⸜ ARMIA, Wojna i pokój, Stage Diving Club DGCD 0125, CD (2025).
⸜ WILLOW AVALON, Southern Belle Raisin’ Hell, Assemble Sound/Atlantic/Tidal, FLAC 24/48 (2025).
⸜ RED HOT ORG, Transa, Red Hot Org/Tidal, FLAC 24/96 (2024)
⸜ G-DRAGON Power, Galaxy Corporation/Empire/Tidal, FLAC 24/48 (2024).
⸜ WILCO, A Ghost Is Born, Nonesuch Records/Tidal, FLAC 24/192 (2004/?).

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THIS TIME THERE WAS NO SHOCK. I heard what I expected to hear, confirmed what didn't need to be confirmed: the company Norma has a patent for excellent sound. Even though I knew by a wide margin how the DAC-2 would sound like in my system, still after the first few albums my head was possessed by good thoughts, thoughts of warm, dynamic, open, sonorous, and dense sound.

The Italian DAC plays in a way that resembles what I hear every day from the Ayon Audio CD-35 HF Edition player. From a conversation with Mr. Enrico Rossi, nota bene – an aficionado of Decca recordings, I knew that this was not an attempt to copy anything, but an personal approach to the subject, just as in the case of the Ayon. It just so happens that these two designers, that is, Gerhard Hirt and Mr. Rossi think about sound in a similar way. So do I.

This sound saturates and energizes the air in our room. When the kick drum strikes on the MAYO NAKANO PIANO TRIO Miwaku album, as the drummer runs over the other drums, it is almost a physical experience. The kich drum doesn't have a quick strike, it's not a “slap”, but that's how it was recorded. And at the same time, the other side of the band is pearly, dense in sonority and multiplicity of sounds. This is not a monotonous hitting of a hi-hat or ride, but a complex, multi-threaded, multi-layered sound that “comes out” towards us.

Although having the characteristics of a warm sound, this presentation is incredibly dynamic. You see, the album in question was recorded digitally, in DSD with a high sampling rate (DSD128). And it sounds better than the vast majority of analog recordings. Also thanks to the incredible dynamics, in which there is no room for brightness or impurities. With the DAC in question, this feature was clear. There was no need to imagine anything.

Whatever one might say, however, it's a DAC that celebrates, almost pays homage to - the midrange. MILTON NASCIMENTO's vocals from the album Courage, were dark, placed quite far from me, blending into the background of other instruments placed by the producer on the listening axis. Although the album was released in 1969, a time when multi-track tape recorders were common, here you can hear it as if the producer had to deal with two tracks and had to accommodate orchestra, band and vocals on them.

And so he did. Although Ampex unveiled the prototype 16-track MM-1000 in 1968, the first commercially available 16-track machine in the world, it didn't go on sale until a year later. And it was very expensive, costing as much as $30,000 US. But it's not the price that's the issue here, but the method – Rudy Van Gelder, who recorded the Courage, recorded everything on stereo tape recorders until the mid-1970s, mixing “on the fly.” Here, you can hear it like this, as if he recorded the orchestra and the band separately, and then ripped it onto one tape recorder.

It was released by CTI Records, so with a great cover and a cool sound, so it sounds a bit like it came from the 1950s even though it's a stereo recording. Norma's converter played it densely, played it warmly, played it dynamically as well – this is bossa nova, after all... But it unequivocally valued the voice and the orchestra behind it. It brought them a little closer and filled the space with them - the reference system shows them more clearly and a little further away.

Placed in the left channel, the guitar was clear and had a selective sound, as did the cymbals in the right channel. And they were the ones that seemed to have the highest energy. Yet it was Nascimento who caught the attention. Remembering his delicate but still beautiful voice from the Milton + Esperanza album he recently recorded with ESPERANZA SPALDING, I was able to sit back and soak in the hot, almost palpable atmosphere of this recording in peace, but the peace that comes from the lack of irritating sound changes. And not because my blood was cooling. There is no shortage of “attractors” in this sound, thanks to the high resolution, this is an internally complex message, not a simple shout: “Hey!” It's all about the inner peace that this DAC brings to the music.

The reference player focuses the sound more clearly, accentuates the lower bass more strongly, and is also slightly more energetic. However, the differences are not large, and without a direct comparison, only “by heart”, will be difficult to notice. It will be easier for us to say what the two devices have in common. Thus, in both cases, the distinctive synth-played bass in ˻ 7 ˺ Nevermind, a track from Popular Problems, an album by LEONARD COHEN released in 2014, was low and dense with the Norma.

The whole was characterized by a excellent sustained pulse. And when the choruses in the left channel came in, though they still sounded as if they were artificially pasted in, yet they still created, along with Cohen's vocals, the atmosphere I wanted. Because the DAC-2 plays in a way that encourages listening, for long sessions, for rummaging through your record collection, for trips to stores or antique stores, for fidgeting with your feet waiting for a shipment from Japan containing your next acquisitions (I recommend the store → CD JAPAN, where I make my purchases). And this is true regardless of the type of music. After all, ARMIA's latest album played just as energetically and coolly.

THERE IS NO HIDING the fact that the DAC-2 was designed with love in its heart for Compact Disc. Norma's boss spoke of his preference, during a visit to “High Fidelity,” and also reiterated it in correspondence we later exchanged. That's why the main inputs are RCA and AES/EBU. We buy a nice CD transport, and quite a few can be found on the market, and we have a great system.

But it's also not that the USB input is flawed. The tested DAC, however, is resolving and true to what it does, and momentarily shows what the difference between physical media and a file is. Once we accept this, then we find that we can buy a file transport as well and enjoy access to streaming, using a service of our choosing.

It will be a slightly less dynamic sound and more tonally constricted And yet... It sounds very good. Still dense, low, and warm. This was the case with both the country-drenched Something We Regret of WILLOW AVALON, and the rockin', straight-out-of-the-80s playing in the track Surrender Your Gender by super group RED HOT ORG. In Power, a track by South Korean rapper Kwon Ji-yong (Hangul: 권지용), better known by his stage name G-DRAGON, the bass hit hard, low, pulling everything forward.

Know this, however, with more refined material we will reach a place where the discrepancy between file and CD will not be particularly large. An anniversary box set of A Ghost Is Born by the band WILCO has just been announced, so I couldn't help but reach for it. It is available on Tidal in 24/192 FLAC files, which sounds very, very mature. So did the DAC-2, which showcased Jeff Tweddy's vocals right in front of me, tightly, densely, and his guitar, as in 2 ˺ Hell Is Chrome, with just the right amount of “whizz” and distortion.

▌ Summary

DAC-2 IS NOT PERFECT, because it cannot be. There is no such thing, and besides, it is somehow not a particularly expensive DAC. At the very bottom it somewhat “lets go” of bass focus, nor does it focus the sound above as well as the reference player. It prefers a warm, dense midrange, although it does not forget its extremes. It resembles, in truth, the sound of the Lumin T3 file player. That is, it puts it all together in a neat whole that smoothly plays any music.

Given its price, however, it must be said loud and clear: this is a very good product, prepared by a man who loves what he does and, as a result, does it well. Which become clear as soon as you start listening to it. We get a DAC that plays low, warm, dense but also dynamic and with a strong treble. We're talking high resolution and surprisingly good selectivity – which, for such a dense sound, is a major achievement. Bass is strong, filled, low. And full rather than punchy. The highs have a lot of weight and energy, but they too sound in a rather sweet way. This gives a sound that a few years ago was reserved only for the most expensive digital equipment. ●

▌ Design

AS WE WERE TELLING YOU, the electronics of the tested D/A Converter are entirely Norma's proprietary development and are identical to what we get in the company's CD players. This is, in fact, the CDT-2 player minus the drive. When you take off the top panel, you can see the place for it, blanked off with a transparent plastic plate. The electronics and power supply are identical.

A board with a circuit that converts this signal to IIS was placed in the USB input. It is plugged into a larger board with the other digital inputs; impedance matching transformers are mounted in front of each of them. On a separate, large board, we find the DAC circuit. This circuit is called A-DAC, where 'A' refers, as the designer says, to “analog.” His idea, he adds, was to make digital sound as much like analog as possible – not LP, but just analog.

The technology is a secret. All that is known is that it is a “combination of digital and analog circuitry” and that it is a multi-bit circuit, not a sigma-delta. The module in question was fully encased in resin and shielded. According to the designer, the idea was to stabilize the temperature of all the components inside. And thermal drift is, according to him, the cause of the artificial and rough sound of digital players.

The D/A converter circuit features a current output, so it needs an I/U converter. This, too, is the company's own circuit, made discreetly and enclosed in a shield. The company selects transistors so that both channels are perfectly matched. Behind this module you can see a small Burr-Brown IC. It converts the negative branch of the XLR output; this is because the priority output for Norma is the RCA output (that is, just like for me). However, if someone wants to take full advantage of the XLR outputs and prefers to send the signal in balanced form, they can order the DAC with the appropriate additional discrete I/U modules - space has been reserved on the board for them.

The digital filter before the converter is also Norma's own idea. It is based on Burr-Brown's DF1706 filter, which means it is an eight times oversampling circuit. Besides, the DAC used in the DCP-2 itself was intended to be a better version of the PCM1704 DAC from the same company, which Mr. Rossi said was “one of the best circuits of its kind” in audio history. The output circuit is not subject to feedback, and it still has a frequency response of 2 MHz. This is to help the signal be as phase-integrated as possible.

The unit is powered by an elaborate power supply with a toroidal transformer wound, as we read, “specifically with audio systems in mind.” Separate secondary winding have been given to the digital and analog sections, and in the circuit we find as many as 24 voltage stabilizers; mains ripple filtering is provided by nice Elna capacitors. ●

▌ Technical specifications (according to the manufacturer)

Supported digital signals:
• USB → PCM up to 24 bits, 384 kHz, DSD up to DSD512
• RCA, optical, AES/EBU → PCM up to 24 bits 192 kHz
Outputs: RCA, XLR
Output voltage (@ 0 dB):
• RCA → 3 V RMS (+10 dBV)
• XLR → 6 V RMS (+16 dBV)

Output impedance: 200 Ω
Frequency range: 0 Hz- 22 kHz, +/- 0,3 dB (limited to the CD standard)
Analog stage, frequency response: 0 Hz-2 MHz +/- 3 dB
Over-sampling: DF 1706, 8 x digital filter
D/A Converter: 24-bit C/A Norma A-DAC Multibit
I/V conversion: I/V conversion with proprietary topology using discreet components

Dimensions (H x W x D): 75 x 430 x 350 mm
Weight: 10 kg

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THIS TEST HAS BEEN DESIGNED ACCORDING TO THE GUIDELINES adopted by the Association of International Audiophile Publications, an international audio press association concerned with ethical and professional standards in our industry, of which HIGH FIDELITY is a founding member. More about the association and its constituent titles → HERE.

→ www.AIAP-online.org