Grimm Audio was founded in 2004 and is based in Eindhoven, the Netherlands. They use the highest level of technical and audiophile knowledge to build audio equipment that leaves a lasting impression on listeners. The MU2 is Grimm Audio’s latest streaming DAC, but it is a lot more than just that. In this article, we will review the Grimm MU2 and we will look at all the exciting things it offers, and whether you should buy it or not for 17,750€, which equals about US$20342.
Grimm MU2 Review
Design And Features
The Grimm MU2 is an all-in-one streamer-DAC-preamp that looks very elegant and simple. It has a matte black finish, along with a rectangular, 3.5-inch display on the front panel. A white LED on the left of the display turns on when the MU2 powers up, and there is a silver-brushed control disc on the top. That’s it, no buttons at all, and no remotes either.
Since there are no buttons, how do you control the Grimm MU2? You do it with the big silver control disc on the top. At first, I found it a little strange, but it quickly became intuitive, and you can tap, press, and turn the disc to control the DAC.
On the back panel, the Grimm Audio MU2 has a coaxial, a TOSLINK, and an AES/EBU input. It also has XLR and RCA outputs, and a headphone jack. You can get the MU2 with an optional 2TB or 8TB SSD, but that will cost you extra. Something strange, the MU2 doesn’t have WiFi, and it streams only from Roon. This was also the case with the Grimm MU1, which was a beast in its time.
The MU2’s digital filter was developed by Grimm in-house, and it is called the “Pure Nyquist” filter. This filter oversamples all the input digital signals to 8 times their base rate, which is more than the MU1’s four times.
The DAC in the Grimm MU2 doesn’t come from an off-the-shelf chip like ESS; it’s an instruction set that has been coded into the MU2’s FPGA board. Grimm calls this DAC the “Major DAC”, and it is a little different from your traditional PWM DACs. It uses a 1.5-bit architecture, which offers a stable noise shaping operation and amplitude linearity.
Special care is taken in the analog signal path to preserve the beauty and transparency of the DAC output signals. The analog signal path is implemented fully symmetrically using very high-quality circuitry, components, and layout. The signal is routed through a first-class, relay-based volume control section so that the analog output of the MU2 can be fed directly into a power amplifier. Additionally, up to two analog sources can be connected, allowing the MU2 to be both the digital and analog ‘hub’ in your HIFI system.
Setting Up The Grimm MU2 With Roon
The Grimm MU2 is very easy to set up. It comes with a manual, and I just plugged it into my speakers and connected it to my network with the Ethernet port. Since the MU2 can serve as a Roon Server (a Roon Server is software that manages your music library, audio devices, and network connections), I downloaded the Roon Remote app and connected it with my MU2, and I was done. You will need to make a Roon account, and you will need to connect it with your music streaming services (Spotify, Tidal, Qobuz, etc.). If you want to display track art on the MU2, then you must download the Grimm Audio extension on Roon Remote; you will also need to designate the MU2 as its output device.
The Grimm Audio MU2 includes everything Roon has to offer, and Roon Remote works perfectly. I connected the MU2 with my Bowers & Wilkins 705 S3 Signatures, and this pairing was insane. I also used a subwoofer, and my choice was the SVS PB17 Ultra Revolution.
Sound Quality
The Grimm MU2 delivers a captivating sound experience that justifies its premium positioning in the high-end audio market. From the moment you press play, the MU2’s custom “Major DAC” architecture and Pure Nyquist filter reveal their sophisticated engineering through an incredibly transparent and natural presentation. The soundstage exhibits remarkable width and depth, with instruments positioned with precision across a three-dimensional space that extends well beyond the physical boundaries of your speakers. Vocals emerge with stunning clarity and body, while the tonal balance remains neutral, never favoring any particular frequency range but allowing each recording’s inherent character to shine through uncolored. The MU2’s ability to resolve micro-details is exceptional, picking up subtle ambient cues, breath sounds, and the natural decay of instruments that lesser DACs simply miss or blur together.
What truly sets the Grimm Audio MU2 apart is its effortless handling of complex musical passages and its ability to maintain composure even with demanding, full-scale orchestral works. The bass response is tight and controlled, extending deep without ever becoming bloated or overwhelming, while the highs sparkle with air and extension that never crosses into harshness. The midrange, arguably the most critical frequency band, is rendered with such naturalness that voices and acoustic instruments sound startlingly lifelike. Whether you’re listening to intimate jazz recordings or expansive classical compositions, the MU2 creates an immersive listening experience that draws you into the performance, making you forget about the technical aspects and simply enjoy the music as the artists intended.
Verdict: Should You Buy The Grimm Audio MU2?
At €17,750, the Grimm MU2 represents a significant investment that places it firmly in the luxury audio category, but for serious audiophiles seeking the ultimate streaming DAC experience, it delivers exceptional value for its price point. The MU2’s combination of cutting-edge digital processing, premium analog circuitry, and thoughtful design creates a product that excels not just as a DAC but as the central hub of a high-end audio system. However, potential buyers should consider the limitations: the lack of WiFi connectivity and restriction to Roon-only streaming may not suit everyone’s workflow, and the minimalist control scheme, while elegant, requires some adjustment. If you’re already invested in the Roon ecosystem, have a wired network connection available, and prioritize uncompromising sound quality above convenience features, the MU2 is an outstanding choice that will likely serve as the foundation of your system for years to come. For those seeking maximum flexibility or working with tighter budgets, exploring other options might be wise, but few products at any price can match the MU2’s combination of technical excellence and musical engagement.