The High-End DAC
with FemtoSecond Pro Audio Clock

I am telling you, its one of the best, cleanest acts I ´ve ever heard. It´s got one of the best headphone sections with all these German features. Mercedes is striving to be as tech savvy as what´s in this deck and look at the **** size of it!

Z HiFi Reviews

Sonus Verus

The Ultimate Sound Experience
WITH all the details.

RME’s ADI-2 DAC FS is a true milestone in many ways. Looking at the multitude of DA converters, USB DACs and dedicated headphone amps available, RME developers felt they all lacked obvious features that are unavoidable to enjoy operation as well as when listening to music. And while many of those devices claim to use the latest state-of–the–art whatsoever converter chip, serious magazines and RME staff were repeatedly disappointed to find that in the end the stellar technical data published in ads and datasheets were nowhere to be found.

So, the time was right, to create a device, which combines all of RME´s pro audio technologies with a superior DA conversion stage, based on the latest electronic components, which actually delivers a pure and perfectly true sound with the given specifications.

Packed into the compact half 19” format factor, this little gem is filled with the finest high-end electronics, offering a reference class conversion from SPDIF coaxial, SPDIF optical (ADAT compatible) and USB to RCA, XLR, TRS and mini-TRS.

As the most versatile DAC available, the ADI-2 DAC offers balanced/unbalanced analog I/Os, an Extreme Power headphone output, a super low noise IEM output, SteadyClock FS, 4-stage hardware output level control, DSP-based signal processing, external power supply operation, Class Compliant USB compatibility, sample rates up to 768 kHz as well as DSD playback. The SPDIF input signal can even be recorded via USB – as one would expect from RME the DAC is a true 2 channel Full Duplex audio interface.

SteadyClock FS

RME´s Pro Audio Clock featuring FemtoSecond Accuracy & complete JITTER Immunity

With SteadyClock FS RME converters deliver a superior pristine signal conversion, with jitter measured much lower than nanoseconds (ns) or picoseconds (ps), in an area called femtoseconds (fs).

Main DAC Specifications

123 dBA
0.00016 %
THD @ 0 dBFS:
0.0001 %
Ch. Separation
> 120 dB
I have a track which I mixed with a kalimba part in the bridge, I know it’s there, but listening on my KRKs with my benchmark interface I would be tempted to EQ it. On the RME, I heard exactly why I had it at that level when I mixed in a commercial studio. At high frequencies, ‘shots’ of delay were clearly audible as they decayed on the RME, whilst my benchmark interface (which was not cheap!) lost the final decays in the mix. The hi-fi unit was comparative to the RME at snare-hit frequencies, but couldn’t match it at the high end. The same was true at the extreme low end: for example, with a sine wave–rich bass part which punches into a verse. The RME reveals the dynamic rise of the waveform, answering that eternal question – is this going to pop-out too much when it’s played in the club?

Resolution Magazine

So first I tested this DAC with my Adam A5Xs, and I compared the sound with my 100 Dollar SMSL Sanskrit DAC which is also pretty great at its price point. I have talked about this in my Adam A5X review, but the RME DAC just took the soundstage and quality of the A5Xs on a totally next level. The depth of the soundstage increased so much that it feels like sound is coming from a point behind my display monitors, and this really opened a new dimension of experiencing sound with my Adam speakers. The biggest difference in the quality of the sound was in the vocals, because when I switched between my RME DAC and the SMSL Sanskrit, the vocals on SMSL Sanskrit felt really bad in comparison because the vocals felt very compressed and artificial. The vocals on the RME DAC were MUCH more natural in comparison, and I never realized what I was missing with the SMSL Sanskrit until I made this comparison. review



RME’s SteadyClock technology guarantees an excellent performance in all clock modes. Its highly efficient jitter suppression refreshes and cleans up any clock signal.

Usually a clock section consists of an analog PLL for external synchronization and several quartz oscillators for internal synchronization. SteadyClock requires one quartz only, using a frequency not equalling digital audio. Modern circuit designs like hi-speed digital synthesizer, digital PLL, 800 MHz sample rate and analog filtering allow RME to realize a completely newly developed clock technology, right within the FPGA at lowest costs. The clock’s performance exceeds even professional expectations. Despite its remarkable features, SteadyClock reacts quite fast compared to other techniques. It locks in fractions of a second to the input signal, follows even extreme varipitch changes with phase accuracy, and locks directly within a range of 28 kHz up to 200 kHz.
The further improved SteadyClock FS technology attenuates even lowest frequency jitter (>1 Hz), provides an even higher jitter suppression at lowest self-jitter, and uses a low phase noise quartz with jitter in the range of femto seconds. Thanks to the highly efficient jitter suppression, the AD- and DA-conversion always operates on highest sonic level, being completely independent from the quality of the incoming clock signal.

SteadyClock has been originally developed to gain a stable and clean clock from the heavily jittery MADI data signal (the embedded MADI clock suffers from about 80 ns jitter). Using the input sources of the ADI-2 DAC, SPDIF, ADAT or AES, you’ll most probably never experience such high jitter values. But SteadyClock is not only ready for them, it would handle them just on the fly.

Watch Video

SteadyClock FS – Reference Class Digital Clocking Explained
Why is it superior in the Pro Audio World.
by RME Audio

The RME boasts some impressive specifications for the price and size offered. By now many objective measurement sites have confirmed extremely low jitter, superb channel matching and separation, flat linearity, extremely low harmonic and intermodulation distortion, close to zero ohms output impedance on the headphone out and a high dynamic range.

Headphonics Review

The sound quality of the ADI-2 DAC FS is superb. Even to my ‘industry
veteran’ ears, and even at 44.1kHz 16 bit, the difference was obvious when compared to the
other four DACs I had available. This is not just a DAC that’s ‘worth a try’ – if you’re looking
for a benchmark two-channel with comprehensive monitoring controls – you
have to audition this.

Resolution Magazine

Learn More about the ADI-2 DAC FS


The Headphone Amps


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