The High-End DAC
with FemtoSecond Pro Audio Clock
Z HiFi Reviews
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.
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.
RME´s Pro Audio Clock featuring FemtoSecond Accuracy & complete JITTER Immunity
Main DAC Specifications
> 120 dB
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.
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.
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.
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.