ytek's products have never been large, nor have they been "glamorous" products. At least until the Manhattan model, whose front flashed like a diamond. Even it was, however, a deeply a pragmatic, common-sense and, above all, extremely functional device. Mytek, owned by Mr. Michał Jurewicz, our compatriot who settled in the USA, grew out of experience in the professional world, mainly recording studios.

No wonder that all of its previous converters - although they do have also the Brooklyn power amplifier in their portfolio, they specialize in this type of devices - offered, for example, a digital signal level indicator, even with momentary and peak reading, on bargraph and alphanumerically. Such knowledge is priceless in the studio. At home, it is usually unnecessary, but it added to Mytek's authenticity.

Although these are really small devices, they have gained the recognition of the most important magazines in the USA and around the world, as well as of many important sound engineers in the industry. And yet, it seems that it is the home audio market that brings them the biggest profits. That is why, having us, music lovers and audiophiles in mind, Mytek in the new versions of their products, build-in also phono preamplifiers, and now they presented two products dedicated for home use – CLEF, the portable DAC/headphone amplifier and the smallest stationary product of this company, DAC and headphone amplifier in one called Liberty DAC.

| LIBERTY DAC

The latest product of Mr. Jurewicz and the Polish HEM Electronics company from Warsaw he works with, where all Mytek devices are manufactured, is really small. Although Brooklyn seemed small, its front wall was 216 mm wide (1/2 rack), compared to 140 mm (1/3 rack) of Liberty DAC it was still quite a lot. As you can see - see brackets - Mytek did not give up their professional origin. I can easily imagine three such devices working in a multi-channel system, occupying space of only 1 rack, or 420 x 44 mm.

Its front panel has an interesting texture, and there is no display, just an array of LEDs. They indicate the selected input, the presence of DSD or MQA signal and the volume level. DSD and MQA are especially important for Mr. Jurewicz. Let me remind you that he was one of the engineers who developed the DoP protocol (DSD over PCM), which allows you to send DSD signal via USB, and is now involved in MQA encoding.

In the Liberty DAC, DSD signal transmission has been upgraded, because this protocol also works for the S/PDIF inputs – the electrical RCA and optical TOSLink. Although we hear more and more often, and I agree with that based on my own experience, that DSD direct transmission gives better sonic results, thanks to the DoP protocol we could experience the magic of DSD recordings years ago without having to use SACDs. Once the DAC receives a DSD signal it will be confirmed by the white color of the diode.

MQA also seems very important for Mytek - it is no coincidence that Mr. Jurewicz is involved in this type of coding both on the side of the studio and of home systems. The Liberty DAC features a certified, working independently MQA decoder. And a LED on its front panel will tell us whether the received signal is fully compatible with what has been coded in the mastering studio: the blue LED means MQA Studio, and the "ordinary" MQA lits the green diode up.

| Functionalities

Even this brief introduction already has shown how versatile the Liberty DAC is. Let's start from the beginning though: it's a digital-to-analogue converter with an adjustable analogue output, featuring a headphone amplifier. It features four digital inputs: USB, two RCAs (S/PDIF), optical TOSLink (S/PDIF) and balanced AES/EBU.

The most versitile one is the USB input, that accepts PCM signal up to 384 kHz and 32 bits, DXD and native DSD up to DSD256 (11.2 MHz). But the others are also impressive because all of them accept PCM signals up to 192 kHz and 32 bits, as well as DSD64 (!) using DoP protocol. The signal from all inputs can also be decoded in MQA.

The selected input is indicated by a blue LED. The same row of LEDs is used to indicate current volume level - the DAC features a digital volume control. The indications are multicolored - when the volume passes the given LED it remains red, and the next one in line turns first blue, then green and finally orange. Only then the red light turns on and the cycle ends. It does not allow the most intuitive operation, but one can get used to it. The problem may be, if one actually needs it, a lack of sampling frequency indication.

There are two analog outputs - unbalanced RCA and balanced big jack ø 6.3 mm (TRS = Tip + Ring + Sleeve). The latter was used due to the small surface of the back panel, where much larger XLR sockets would not fit anymore. There is another stereo output on the front panel - a large ø 6.3 mm jack for headphones. The headphone amplifier delivers up to 3 W at 300 Ω and supports loads down to 0.1 Ω. It will drive any headphones. The converter is powered by an AC power cable or from an external 12 V DC power supply.

| MQA Studio / MQA

Although MQA is a novelty that is constantly being discussed, it is necessary to know that there are "various" MQAs. The company divides them into two categories: MQA Studio and MQA. The former is the better quality one. It is used when a representative of a record company, musician or music producer who has power of attorney to approve the process is present during the material coding. However, it requires comparative listening and active participation in them. The blue color means that the encoded file has an official "imprimatur" and the company claims it is "identical" to the original hi-res file.

The green LED will lit up when the file is encoded in the MQA, but without the participation of people associated with the recording or label. According to Bob Stuart, MQA director, signal resolution and sound quality are the same as in MQA Studio, but we are not sure about their origin.

Digital-to-analogue converters are currently the most multifunctional "basic" products on the audio market. One needs to evaluate the sound from the S/PDIF and USB inputs, use different types of sources, such as a computer, a streamer and CD transport, and try out different types of headphones if the headphone amplifier is part of the device.

This time the listening session was divided into several stages, which I present in the order related to the quality of the sound that I achieve in my system. I prefer the sound of CDs, so in the first step I connected the digital output of the Ayon Audio CD-35 HF Edition player to the RCA Liberty DAC input using the Acrolink Mexcel 7N-DA6100II digital cable. In the second one I connected the Fidata HFAS1-XS20U file player to the converter using the Curious USB cable. And finally, I listened to Tidal, including MQA and MQA Studio files from the Lumïn T1 player as a file transport, using the Acrolink digital cable again. Separately I tested the headphone output.

Recordings used for the test (a selec- tion)

| Compact Disc

• Bogdan Hołownia, Chwile, Sony Music Polska 5052882, „Pre-Mastering Version”, Master CD-R (2001)
• Diana Krall, Wallflower, Verve/Universal Music LLC UCCV-9577, “Deluxe Edition”, SHM-CD + DVD (2015);
• Jean-Michel Jarre, Magnetic Fields, Dreyfus Disques/Epic EPC 488138 2, CD (1981/1997)
• Nat ‘King’ Cole, The Nat King Cole Love Songs, Master Tape Audio Lab AAD-245A, „Almost Analogue Digital”, Master CD-R (2015);
• Starboy, Starboy, XO
• Republic 5727592, CD (2016)

| Hi-res Files

• Depeche Mode, Playing The Angel, Mute Records cdstumm260, DSD64 (2005)
• Eric Bibb, A Selection of analogue Eric Bibb, Opus3, DSD128
• 2xHD. DSD, USB Flash, DSD64/DSD128
• 2xHD. PCM, USB Flash, WAV 24/192
• FIM Super Sound! I, First Impression Music FIM DXD 066 USB, Promo USB Flash, FLAC 24/176
• Anne Bisson, Blue Mind, Camilio Records CAMUSB141, USB Flash, FLAC 24/96 (2009)
• Leonard Cohen, Popular Problems, Sony Music Labels SICP-4329/HDTracks, WAV 24/96 (2014)

Tidal

• Jackson Browne, Late For The Sky, Asylum Records INR 04191/Tidal, MQA Studio 24/192 (1974/2015)
• Jethro Tull, Aqualung (Steven Wilson re-mix), Chrysalis ‎0825646146611/Tidal, MQA Studio 24/96 (1971/2015)
• Kendrick Lamar, Black Panther. The Album Music From And Inspired By, Top Dawg Entertainment ‎00602567364306/Tidal, MQA 24/44,1 (2018)
• Melody Gardot, Live in Europe, Decca Records/Tidal 602557654882, MQA 24/48 (2017)
• Motörhead, Under Cöver, WEA | Silver Lining Music/Tidal SLM083P01, MQA Studio 24/48 (2017)

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Japanese issues available at

The Liberty DAC compared to the Ayon player shows some interesting things with Compact Discs. First of all, how amazingly the digital technology has changed and how things that were once considered disqualifying this technique from high-end level are now in its mainstream and also on top. I am talking about treble first and foremost. The first reactions of music lovers to the CD format were unflattering. They pointed out harsh, rough and metallic cymbals, wheezing sibilants and "emotional frigidity".

The Liberty DAC seems to tell us that we these times are behind us. The treble is smooth, resolving and well differentiated. It can be heard very well especially with CDs that offers above mentiones sonic qualities themselves, as the master CD-R with Bogdan Hołownia Moments. The DAC dealt equally well with the more “commercial” discs such as Diana Krall's Wallflower for example, a much more mainstream recording than her previous ones.

The point is that Krall's voice, recorded very close to the microphone, has clearly highlighted components that harden this performance, including sibilants. But these are not bright, only distorted. The Mytek converter presented them in a very natural way, because it did not brighten them up, did not harden them additionally, letting music flow, develop without hurry, for example in the California Dreaming - this is what "naturalness" means for me, ie high fidelity to the source material.

The other band's extreme is strong, full, "swinging". Both previously mentioned discs, with double bass as a rhythmic instrument, as well as Jean-Michel Jarre's electronics from Magnetic Fields, as well as the great performance of Starboy supported by the Daft Punk, were based on a solid foundation. I can not imagine a system that would run out of bass. I will say more – the Liberty DAC, can “save” many too thin-sounding, too light systems, restore their vitality.

It's just that it is not particularly deeply extended - I'm talking about the basic octave - or excessively tight and controlled bass. Extinguishing the pulse is good, but without a clear “cut-off", the sounds end in a gentle roll-off, even if - like in Jarre's case, they were recorded with a clear "cut-off" after the impulse. However, since the Liberty DAC does not over-extend it, we get what I wrote about, i.e. energetic, powerful, rocking bass.

What differs this converter from my reference and what best situates it on its price shelf is the vitality and resolution of the midrange. This part of the band is slightly quieter than the extremes and not so vital. It helps in mastering the lower quality pop music recordings, for example like in the case of the Pet Shop Boys from the Super, but it does not let the sound develop. This is not a nuisance, I see it rather as a deliberate choice, intended to civilize the sound. However, it is worth knowing about it.

| PCM hi-res/DSD

It's just that this is the element that improves slightly with the hi-res signal, mainly PCM, but also with DSD. With high resolution files, the Liberty DAC sounds equally well, smoothly, rhythmically, and has a strong, powerful lower end. I would even say that the USB input was the preferred one for me, although it is almost always the opposite. Assuming that we have a well-configured computer, I do not see the need to connect this DAC to an external CD transport.

Although, when playing Compact Discs played from external transport, we get a more credible sound stage and a larger size instruments, the differences are not significant enough to make it a problem. The more so that the high resolution files offer something else – a higher energy of the midrange and better controlled bottom, that with CD quality files is not as good. The USB input shows the Liberty DAC from its best side also because the presentation is very well organized. Both with DSD files, for example Depeche Mode (DSD64) and Eric Bibb (DSD128), as well as PCM hi-res, e.g. Harvest Neal Young (WAV192 / 24), the performance was very smooth, powerful, just cool.

| MQA

Neither MQA nor high resolution files nor even DSD256 solve any problems in the quality of recordings and the quality of playback devices. If we listen to poorly recorded music or use a poor quality device, it will result in a poor sound, period. Both sides of the equation must be satisfied, i.e. the music and sound must be of good quality, and the devices used to play it must be good performers too.

I am writing this because the MQA coding is not a "remedy for all evil", treating it as a cure for quality problems is a mistake. Because Motörhead from the Under Cöver will remain Motörhead (MQA Studio 24/48, blue diode), and Melody Gardot with Live in Europe will be the same Melody Gardot (MQA 24/48, green diode). So we will listen to good music, but still deal with the problems of this type of recordings. The MQA will improve some of its aspects, above all smoothness and fluidity, but it will not save dynamics and will not discipline the bass.

And only when we listen to high-quality recordings like Aqualung by Jethro Tull in the Steven Wilson remix (MQA Studio 24/96, blue diode) or the fantastic album Late For The Sky by Jackson Browne (MQA Studio 24/192, blue diode) - only then can one can say that Liberty DAC sounds really good and that Tidal with MQA files - and even better with MQA Studio - is a full-fledged source of signal. (album Late For The Sky was discussed in the "Hi-Fi News", March 2018, Vol.63, No. 02).

The Liberty DAC is an offer for a slightly different group of customers than the more expensive Mytek devices - this is how I see it at least. With a limited budget, manufacturer had to take some direction and then compromise; this is how planning looks like for each device, no matter how much it costs. For the Liberty DAC, the precision of performance was replaced with smoothness and fluidity. The "big" converters were, to a large extent, studio devices, in which neutrality was the most important quality and obviously the designers tried to add as little as possible to the sound. This Mytek DAC is different, it sounds more natural and you can hear that this time the job was to take away as little as possible - that's the difference between neutral and natural sound.

The result is an extremely versatile, nicely made, robust digital-to-analogue converter. I had most fun with it while using the USB input receiving signal from both, the Fidata player and my computer. But Lumïn and Tidal, listened to using the S/PDIF digital cable, also sounded so cool that I did not feel a need to change anything. No, this is not the best sounding DAC in the world, because the midrange energy is limited, and thus also its expression, and the bass is not controlled in a particularly restrictive way; it does not go too low either. It is though powerful.

Summary

The Liberty DAC is such a universal device that regardless of how one wants to use it, it will do its job very well. However, I would say that its real "me" reveals itself with high resolution files, also those played from Tidal, encoded in MQA. Plus there is a great headphone amplifier on board, thanks to which you will not need a separate device, even for expensive headphones! Congratulations!

The Liberty DAC is a digital-to-analog converter with an integrated headphone amplifier. It is relatively small, but solid and nice looking. The housing is made of steel sheets and placed on small rubber feet. Its front panel features a characteristic texture. There is a row of LEDs on it, indicating the selected input and the volume level, the volume knob, pressing of which allows user to select inputs. There is also a 6,3mm headphone output and a diode informing about the synchronization between the signal source and the "DAC". The DSD signal turns it white while the MQA turns it blue (MQA Studio) or green (MQA). With another type of signal, the LED is orange.

The electronic circuit is assembled on one printed circuit board. Next to it one finds a Mean Well switching power supply, shielded. I think that replacing it with an external, high-quality linear or even battery powered power supply could significantly improve the sound quality. It's good, then, that a 12 V DC socket has been added on the back panel allowing such replacement. This is good news for manufacturers of this type of accessories, but it would be nice if this type of power supply was also proposed by Mytek, for example in a similar looking housing as the Liberty DAC's. But this power supply, that is on board, is good enough - after the switched power supply the voltage is filtered and stabilized in many sections.

The signal from the USB input goes to a large XMOS chip in which the software written by Mytek software engineers has been implemented. The RCA input is buffered with a matching transformer and, together with the Toslink, it shares a digital receiver, the AKM AK4113. DAC chip is tiny, it's the ESS9018K2M, the same one that was used for the original Brooklyn DAC. Next to it one finds a high quality word clock system with a very low jitter of 10 ps.

The symmetrical analogue output was built using two integrated circuits per channel. The marking were removed from them. They work with Wima capacitors and SMD resistors. The output features relays - RCA sockets are solid, gold-plated, while the jack-type outputs are not gold-plated.

The headphone output is also not gold-plated. It is driven by a chip with worn marks. In its power supply six additional Rubycon capacitors operate.

Technical specifications (according to manufacturer)

Digital inputs:
- USB2 Class2 | PCM up to 32/384, DXD, DSD up to DSD256
- AES/EBU | PCM up to 32/192, DSD64 DoP
- 2x S/PDIF RCA | PCM up to 32/192, DSD64 DoP
- Toslink | PCM up to 32/192, DSD64 DoP

Decoder: MQA
Dynamic range: 127dB (in the manual I found a different value - 130dB)
Output signal (max): 2.5V RMS
Output impedance: 75Ω
Headphone output: 300mA, 3W
Dimensions (S x G x W): 140 x 216 x 44mm
Weight: 1kg