Home Grimm Audio MU2 – A Major DAC redesign

Grimm Audio MU2 – A Major DAC redesign

20

Pros

  • Inaudible
  • Lots of headroom
  • All features at top tier
  • No more upgrade-nervosia

Cons

  • It's not ours!

Price: € 17999

Build quality
Usability
Sound
Price
Alpha-Audio Approved
Grimm MU2

Intro

For us, it was one of the highlights of the High End Munich 2023: the introduction of the Grimm MU2. So we couldn’t wait until we had one in our hands to check it out. Does it disappoint after all the “high hopes”? Well … you already know that answer. But that doesn’t take away from the fact that we’d like to take a closer look at this beautiful device.

A few years back, Grimm introduced the MU1. That was a pretty “disruptive” device. It’s a streamer with a Roon core (or server) and as icing on the cake: far-reaching upsampling of the digital signal. That will give better results with all dacs, connected to it. Due to its excellent sound characteristics, the Grimm MU1 ended up in many a reference system. And rightly so.

Grimm MU2

The Grimm MU2 is not the successor to the MU1. It is a complementary product for those who do not want to work with a separate d/a converter. The Grimm MU2 is a streamer with the same Roon core as in the MU1 and now also a built-in d/a converter. A very special converter, about which more later.

But it doesn’t stop here. In fact, the MU2 also has an analog preamplifier with analog volume control. And it has a headphone amplifier. This signal path is also completely analog: no analog-to-digital conversion or other DSP-like conversions: it simply involves a relay which keeps the signal path as short as possible.

Then the price for all this beauty: 18000 Euro. Yes: a lot of money. We will agree on that. But realize that you are not only buying a streamer, but also a Roon core (unfortunately the license is not included; we would have liked that), top-of-the bill d/a converter, a headphone amplifier AND a wonderful analog preamp. All in all, the MU2 is a very interesting package deal!

Type test
Single Test
Inputs
  • Analog RCA
  • Analog XLR
  • Digital Coaxial
  • Digital Optical
  • Digital AES
  • Streamer ethernet
Outputs
  • Analog RCA
  • Analog XLR
Product type
Streamer
Max samplingrate
24 kHz
Max bit depth
192 bit
Weight
4.5 Kg
Dimensions
  • Width: 36 cm
  • Depth: 30 cm
  • Height: 9 cm
Production country
Netherlands
Sound Samples
Measurements
Grimm MU2 - PSU noise
Grimm MU2 - PSU noise
Grimm MU2 - PSU noise - zoomed
Grimm MU2 - PSU noise - zoomed
Grimm MU2 - Ethernet noise
Grimm MU2 - Ethernet noise
Grimm MU2 - Analog pre-amp - THD+N
Grimm MU2 - Analog pre-amp - THD+N
Grimm MU2 - Analog pre-amp - response and phase
Grimm MU2 - Analog pre-amp - response and phase
Grimm MU2 - Analog pre-amp - Crosstalk
Grimm MU2 - Analog pre-amp - Crosstalk
Grimm MU2 - Analog pre-amp - 2 volt out - XLR
Grimm MU2 - Analog pre-amp - 2 volt out - XLR
Grimm MU2 - AES-in - THD vs Freq
Grimm MU2 - AES-in - THD vs Freq
Grimm MU2 - AES-in - THD vs amplitude
Grimm MU2 - AES-in - THD vs amplitude
Grimm MU2 - AES-in - noise floor - 24-176
Grimm MU2 - AES-in - noise floor - 24-176
Grimm MU2 - AES-in - response
Grimm MU2 - AES-in - response
Grimm MU2 - AES-in - Noise - Interference
Grimm MU2 - AES-in - Noise - Interference
Grimm MU2 - AES-in - Jtest
Grimm MU2 - AES-in - Jtest
Grimm MU2 - AES-in - IMD vs Amplitude
Grimm MU2 - AES-in - IMD vs Amplitude
Grimm MU2 - AES-in - imaging - 24-48
Grimm MU2 - AES-in - imaging - 24-48
Grimm MU2 - AES-in - Dynamic range - volume 0
Grimm MU2 - AES-in - Dynamic range - volume 0
Grimm MU2 - AES-in - DAC response -3dB
Grimm MU2 - AES-in - DAC response -3dB
Grimm MU2 - AES-in - DAC reseponse 192 kHz
Grimm MU2 - AES-in - DAC reseponse 192 kHz
Grimm MU2 - AES-in - DAC lineairity
Grimm MU2 - AES-in - DAC lineairity

Winkels met Grimm

Hooikade 13
2627 Delft, Zuid Holland, NL
St. Ceciliastraat 28
5038 HA Tilburg, NL
Vijlen, Noord Holland, NL
Beethovenstraat 9-b
1077 HL Amsterdam, Noord Holland, NL
Hennesweg 20
6035 AD Ospel, NL

20 COMMENTS

  1. Jaap — The “Notify me of new posts by email” has never notified me.

    I wonder what effect your almost entirely not evaluating the better tube gear is affecting your view of what’s possible. It’s the question I asked myself after many years with a PS Audio Directstream I dac.

  2. Thanks, that’s helpful. Should I take it you don’t deal much with tube gear? I’m under the impression that LampizatOr being Polish is ubiquitous at shows in Europe, invariably with top end systems, and has a good following there. VAC being American (Florida), I’m not sure about, although in the U.S. their amps/preamps often show with Lampi and Von Schweikert speakers.

  3. I had a grimm mu1 on test, it wasn’t a bad device, but I personally don’t like what’s inside the box and the mu2 didn’t convince me either, no linear power supply, too small a box and too few parts which in my opinion are not worth 18000eur, MU1 played clean, detailed but to me it was a bit sterile and clinical and also thin with less space. For a similar price, I finally bought the playbackdesigns MPD8, which seems to me more musical, fatter and at the same time very detailed, but I would definitely like to listen to the MU2 as well

  4. Hi, I know Bruno Putzeys has worked together with the people at Grimm and I think as designers they are a little bit of the same school. In Bruno’s Mola Mola Tambaqui DAC he has also some novel ways of doing D/A conversion. It would be interesting to hear if there are similarities in the sound of the Grimm MU2 D/A converter compared to Mola Mola Tambaqui.
    It sounds like the Grimm MU2 D/A converter is really special. If it’s that good it would be of interest to see a pure consumer D/A for all of us that don’t stream. It sounds like Grimm are already doing D/A converters for professional use. Best regards.

    • I have heard the Tambaqui a few times, but I am not very familiar with it. I have heard a lot of different DA converters though, and I cannot recall any other DA converter that doesn’t sound so unlike a DA converter as the MU2. So that rules out the Tambaqui as well.

      It is very hard to put down in words. No, it isn’t like vinyl. No, it doesn’t sound ‘more analogue’. It is not HiFi anymore. It is ‘just music’.

  5. Informative review. Before I upgraded from ATC SCM 40A to the 50 ASLT (and subs), I questioned others online about the Grimm active speaker(s). In particular, I asked if it had at least a touch of warmth, which I find need of for musical enjoyment vs. hardware listening. Without exception, Grimm owners steered me away. In light of that, I’m wondering where the MU2 fits in. I currently use a Lampi Golden Gate 3 dac, VAC Master preamp and modified digital only Oppo as a primary source for CDs and files from an SSD (USB). Streaming is in the future. Thanks,