RME Audio RME ADI-2 DAC FS review: Outstanding D/A conversion

Best Prices Today: RME Audio RME ADI-2 DAC FS desktop DAC and headphone amp

RME Audio’s RME ADI-2 DAC FS is a desktop device with fantastic sound and an appealing throwback design that gives off an old-school electronics lab vibe. This DAC has a lot of capabilities and a rather steep learning curve if you want to explore all its features. The good news is that anyone can treat it as a plug-and-play device and get their money’s worth without any of the advance tweaking that’s available.

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The RME ADI-2 DAC FS’s build quality

The RME ADI-2 DAC FS measures 2 x 8.5 x 5.9 inches (HxWxD) and weighs just 2.2 lbs. That’s a substantial piece of real estate on a cramped desktop, but it’s a very small footprint if you decide to use it in a component audio system.

There are 1/4-inch and 3.5mm inputs, so you can use the unit with almost any headphone or in-ear monitor you’d like. The unit accepts input from S/PDIF coaxial, S/PDIF optical (ADAT compatible), and USB. In addition to the headphone connections, the DAC sends output via unbalanced RCA and balanced XLR connectors.

The REM ADI-2 DAC FS features a customized version of the ESS ES9028Q2M digital-to-analog converter. That customization allows for some impressive specs, like noise levels of 123dBA, distortion less than -120dB, or THD+N of -116dB. The IEM (in-ear monitor) output has a low noise level of -121dBu.

The unit also features RME’s custom SteadyClock FS, software designed to improve synchronization of the digital signal and reduce jitter. The off-board power supply resides in a brick that attaches to the unit.

The RME ADI-2 DAC FS comes with a thick manual that continues the throwback vibe with a spiral binding. There’s a wealth of tweaks you can make via the button and knob array on the front panel, with the results showing up on a relatively high-res screen that displays its functions with fonts and a UX that recalls 20th-century interfaces from the low-res video era. The best part is that the display shows levels across 30 frequency bands during playback, offering a visual cue that throws back to the days of graphic equalizers in home audio systems.

That’s not really a knock on the device, because that throwback oscilloscope workbench vibe is part of its charm. If you want to get the most out of this DAC and explore its full capabilities, you’ll need to settle in and RTFM to unlock the device’s full potential. That said, the market for a $1,300 DAC is likely to be populated by audio aficionados who are looking for more than just a plug-and-play experience.

If you’re a Windows user, you should be able to download and install RME’s DigiCheck software to inspect and evaluate your audio streams. There is a Mac OS version available for download on the website, but it doesn’t work with the Ventura OS and/or the M1 chip, so I wasn’t able to include it in my testing.

One excellent feature is a Loudness function that also recalls the Loudness button on vintage receivers. Turn on Loudness and the ADI-2 boots bass and treble, so you get a better listening experience at low volumes. The setting brings back details that tend to disappear at low volume. If you’re not completely happy with the default version of Loudness, RME will let you customize the setting after you do your deep dive into the manual.

The remote has large and well-spaced buttons. Everything’s labeled and, while it might not be sleek or minimalist, it’s incredibly easy to use.

REM AD-2 DAC FS listening tests

I evaulated the REM ADI-2 DAC FS with a Focal Celestee closed-back headphone, the Audeze MM-500 open-back headphone, and the Sennheiser IE 900 in-ear monitors. The DAC showed off the strengths of all three headphones, but the Sennheiser IEMs particularly shined with the ADI-2.

The RME ADI-2 DAC FS sounded great across the board, it especially excels at reproducing acoustic instruments in genres like classical, jazz, and rock. A highlight was a 24-bit/192kHz Qobuz stream of R.E.M.’s “Nightswimming,” from the band’s 1992 album Automatic for the People. The track is mostly just vocals from Michael Stipe, accompanied by Mike Mills on piano, but there’s a thrilling string arrangement by Led Zeppelin’s John Paul Jones. The whole track peaks with an oboe joining the mix late in the song.

In this track, every instrument sounds natural and there’s considerable space in the mix when played back through the ADI-2. This stream bests the CD and vinyl versions and illustrates the case for high-resolution audio as well as any recording I know.

The ADI-2 can also handle the low end from tracks like “Privileged Rappers” from Drake and 21 Savage’s 2022 album Her Loss. The bone-shaking bass seems intentionally designed to distort when played back on low-end speakers, but this DAC manages to deliver the intended experience without breaking up at the bottom.

I also tested the RME ADI-2 DAC FS with a component system that includes a NAD C545BEE CD player, NAD S100 stereo preamplifier, and a NAD 2400 Monitor Series amplifier and vintage B&W P5 floorstanding speakers.

I first listened to an early CD pressing of Boston’s self-titled debut album with the NAD C545BEE CD player’s built in Burr-Brown 14-bit DACs. I like the sound of this unit so much that I taught myself to replace the laser when it died a few months back.

I connected the CD player to the RME ADI-2 DAC FS with a S/PDIF coaxial cable and the ADI-1 to my NAD S100 with RCA cables. The results blew me away. I chose this Boston album because of the prominence of acoustic guitars in the mix of a rock album, and the reproduction of those guitars is breathtaking, with far more detail than I would’ve expected from CD mastering in the late 1980s.

The decay on Brad Delp’s lead vocal effects and Tom Scholz’s processed electric guitars is also consistently impressive. This is an album that can come across as an undifferentiated wall of sound when broadcast via FM radio compression, and I can hear individual guitar parts when Scholz’s stack doesn’t line up perfectly. The whole experience is making me reconsider my attachment to the NAD CD player. Maybe it’s time for an upgrade—or at least an investment in an external DAC.

Bottom line opinion of the REM ADI-2 DAC FS

The REM ADI-2 DAC FS sounds great out of the box, so there’s no need to stress about how complex the controls for the unit can be. If, over time, you develop an interest in tweaking the sound and playing with the parametric EQ settings, the comprehensive and well-written manual can help as you look to expand your sonic interests.

It’s also versatile. While I primarily used it as a desktop DAC and headphone amp, it offered a great upgrade when I bypassed the DAC in my NAD CD player. When the ADI-2 DAC is connected to a good pair of active speakers, the combo can make for a great listening setup for digital music. The REM ADI-2 DAC FS offers amazing sound for the price and many features that aren’t otherwise available in this price range. If you aren’t intimidated by its capabilities, this is a DAC that works great out of the box but gives a user room to grow as they learn more about the complexities of high-end audio.

Best Prices Today: RME Audio RME ADI-2 DAC FS desktop DAC and headphone amp