It currently supports only Roon. However, there is an update coming out in 2022 that allows it to be used with other controller software. I assume that means they will be adding UpnP/DLNA support.
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Grimm MU-1 server review - A new force in digital source?
- Thread starter Nevillekapadia
- Start date
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Hi, new member here. Best audiophile Forum IMO. Most informative, most respectful, covering the space broadly and deeply.
I am currently streaming from a Mac mini / Roon core through WiFi into a Lumin U1 (and into a Holo Audio May DAC). I feel the next thing to get to the next level of SQ is to upgrade my current server to a Grimm Audio MU1 (to replace the Mac mini / Lumin U1 combo).
Can anyone share their experience or thoughts about this? Do you feel the MU1 will be a better server / streamer than the Mac mini / Lumin U1 combo?
Thank you in advance.
Philippe
I am currently streaming from a Mac mini / Roon core through WiFi into a Lumin U1 (and into a Holo Audio May DAC). I feel the next thing to get to the next level of SQ is to upgrade my current server to a Grimm Audio MU1 (to replace the Mac mini / Lumin U1 combo).
Can anyone share their experience or thoughts about this? Do you feel the MU1 will be a better server / streamer than the Mac mini / Lumin U1 combo?
Thank you in advance.
Philippe
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Short answer, absolutely! No question about it. Not even close. (Yes I own an MU1)
Welcome to the forum as a new member Philippe.
The Grimm MU-1 is an outstanding piece for musical playback with all the fine details without drawing any attention to any particular characteristics of musical playback. In short, it does everything consistently extremely well.
I have been a user since Dec'19 and there are times I find it hard to switch off, even after 4-6 hours of continuous musical playback listening.
With Holo Dac being a R2R dac, it will suit that ideally as the DAC deters from upsampling the incoming signal.
With upgrades coming from Grimm whenever necessary, this server will bring any listener immense pleasure.
I like the concept of this server, it could be awesome combined with NOS DACS.
The only handicap I see is that it only upsamples up to 192khz via AES/EBU. It should have a modular I2S output (that could be changed depending on the DAC you connect it too) to allow for higher upsampling rates, like ie 384/768khz. I see it has an I2S output but is reserved for Grimm products, so it is not compatible with different DACS. Many lower priced DDCs like Denafrips have multiple I2S outputs, so it shouldn't be a problem to implement.
(Edited because I wrote inputs instead of outputs).
The only handicap I see is that it only upsamples up to 192khz via AES/EBU. It should have a modular I2S output (that could be changed depending on the DAC you connect it too) to allow for higher upsampling rates, like ie 384/768khz. I see it has an I2S output but is reserved for Grimm products, so it is not compatible with different DACS. Many lower priced DDCs like Denafrips have multiple I2S outputs, so it shouldn't be a problem to implement.
(Edited because I wrote inputs instead of outputs).
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Hello Marmota,
The Grimm uses and FPGA card that converts everything to 176khz or 192khz. It is the output from this card at these set outputs, that takes away all the digital noise and grunge we get from just native signal rates.
I have several DSD recordings from single, double and quad that get down sampled to the 192khz. And the output of that is superior, to just a native rate signal fed into a dac, via USB or Ethernet. I cannot speak for I2S as I have not experimented with it myself.
Clearly Eelco Grimm and Guido Tent were so confident of what they were doing (after all they created and were recognised for their top A/D DSD converter) that it was a game changer for them too.
Quite often if it is a good recording and it impresses you, the sampling rate is never the end game defining factor.
The MU-1 is also paired with a well executed DAC like the Mola-Mola which upsamples everything back into DSD for conversion. So it is the execution of the components rather than the higher signal rates that deliver the musical enjoyment.
USB and Ethernet both have their issues (according to the Grimm team) and hence the AES/EBU output is used for this purpose.
So implementing these outputs is not a problem, but they won't deliver the same musical finesse as the 176 or 192khz outputs.
I hope my explanation is understandable. I'm not the greatest when it comes to technical explanations.
Thanks for reading my post.
With all due respect I don't see how that is relevant with regards to what I posted tbh. I didn't even mention ethernet or USB.
The MU-1 may be great, but it would be even better with an I2S output that sends the oversampled signal at higher rates or even as DSD depending on the DAC connected to it. That would be less steps to achieve the same goal, and as such better. In fact, the MU1 has an I2S output for doing exactly what I described, it is just reserved to use with only Grimm products. I've circled it in red so you can see it clearly:
It would be nice if they could also offer that superior data transfer protocol for use with different DACs that are not the Grimm LS1 speakers instead of just leaving the relatively inferior AES/EBU as the only option.
This diagrams explain well why I2S is better than S/PDIF or AES/EBU and why Grimm uses the superior I2S output for their products instead of AES/EBU outputs.
As I said, a modular I2S output would be a nice add on that would improve the performance with different DACs that offer I2S inputs. Nothing wrong with it IMO.
The FPGA card supports AES/EBU output to be connected to an input available on most available DAC's.
There are fewer DAC's with I2S inputs as compared to AES/EBU.
Whereas the I2S (RJ45) you point out too, is a proprietary connector mean for the LS1 which has both data and control signals sent through it.
As Grimm mentioned to me that you can get the higher resolution signals like DSD/384khz PCM out through their USB ports (as they work 2 way -input and output), which is what you are looking for with your purpose of higher sampling rates (but through an I2S), it will then not use the FPGA card which holds the performance benefits.
At the end of being all caught up in the technicality of supposedly assuming by yourself that an output would improve the performance, I am sure Grimm would have done so if every DAC had this type of input.
And if you feel that AES/EBU is an inferior connector, it all comes down to the execution behind it that makes or breaks it.
Thank you for taking the trouble to showcase your reply with all the technical details. As I mentioned, I am not so savvy on this but prefer letting my ears be the guiding factor. Be it either an input or the entire package.
There are fewer DAC's with I2S inputs as compared to AES/EBU.
Whereas the I2S (RJ45) you point out too, is a proprietary connector mean for the LS1 which has both data and control signals sent through it.
As Grimm mentioned to me that you can get the higher resolution signals like DSD/384khz PCM out through their USB ports (as they work 2 way -input and output), which is what you are looking for with your purpose of higher sampling rates (but through an I2S), it will then not use the FPGA card which holds the performance benefits.
At the end of being all caught up in the technicality of supposedly assuming by yourself that an output would improve the performance, I am sure Grimm would have done so if every DAC had this type of input.
And if you feel that AES/EBU is an inferior connector, it all comes down to the execution behind it that makes or breaks it.
Thank you for taking the trouble to showcase your reply with all the technical details. As I mentioned, I am not so savvy on this but prefer letting my ears be the guiding factor. Be it either an input or the entire package.
aangen, thank you for your answer. May I ask what server / streamer you used before adopting the MU1 (if any)?
marmota, thank you for your thoughts on this. Do you recommend considering a specific server / streamer (with I2S output) instead of the the Grimm Audio MU1? Thanks?
Nevillekapadia, thank you for your kind welcome. Can you share what server / streamer your used before the Grimm MU-1 (if any)? Thanks.
Hi pmorali,
Before the Grimm, I used a MacBook Pro (Roon and Audirvana software) into a Playback Designs USB-XIII interface box which then was connected to the DAC via it's proprietary P-links.
I held off buying any server, till I was confident that the streaming signal would sound as good as my CD transport in my Playback Designs MPS-5 Ver2.
Kind regards
Neville
None in specific, depends on the DAC (plenty of brands offer streamers to compliment their DACs, such as Rockna or Playback designs to name a few) and there are plenty of good streamers out there, haven't heard the Grimm so can't comment on how it sounds compared to others.
I started with a Fidelizer Pro PC. Then switched to a Euphony PTS. Then to a Pink Faun 2.16. Finally the Grimm MU1. I am not searching for a replacement. I think the MU1 is endgame quality. I wonder if in the future they will add support for two AES/EBU cables to handle higher bitrates. I don't think I need it, but I am curious. DSD256 through the Grimm is totally enjoyable, even though it is downsampled.
Yesterday, I installed a Grimm Audio MU1 for a week audition. It's brand new.
It's connected to a Lampizator Baltic 3 DAC via AES and USB. The Baltic 3 is optimized for USB, and sounds best using this input, so I'm comparing both inputs using the MU1.
4 FPS upsampling is selected on the MU1. Source is Roon/Qobuz streaming files.
AES interconnect cable is UP-OCC silver.
I found the sound yesterday via AES and USB to be virtually identical. Honestly, I was expecting much more from the Grimm's AES output.
Hans Beekhuyzen said in his MU1 review:
I'm not hearing ease, relaxation or tape recorder analog (I'm familiar with tape recorder analog).
Any thoughts?
It's connected to a Lampizator Baltic 3 DAC via AES and USB. The Baltic 3 is optimized for USB, and sounds best using this input, so I'm comparing both inputs using the MU1.
4 FPS upsampling is selected on the MU1. Source is Roon/Qobuz streaming files.
AES interconnect cable is UP-OCC silver.
I found the sound yesterday via AES and USB to be virtually identical. Honestly, I was expecting much more from the Grimm's AES output.
Hans Beekhuyzen said in his MU1 review:
I'm not hearing ease, relaxation or tape recorder analog (I'm familiar with tape recorder analog).
Any thoughts?
Since all systems are different, I wouldn't pretend to understand how the MU1 might or might not work in your setup; however, in my own system the MU1 took weeks to sound its best (and improved slightly over months). If the demo unit has no hours on it, the dealer didn't do you any favors by not breaking it in, therefore IMO the dealer should give you sufficient time to hear it as its best. Less than two weeks is not enough time if it is brand new (IMO, of course).
Leave the unit on at all times and keep running music through it. I hope you have enough time to hear some of what it brings. This bit of gear is all about musical engagement.
@PYP, thank you for your comment.
I will ask if I can extend the audition. The dealer seemed pretty flexible in that regard.
I'm not going to be too critical about the unit being new, because the dealer ordered the demo unit specifically because I requested a demonstration and they didn't have one in stock. As soon as it arrived, they contacted me and I picked it up.
Otherwise, as I was asking around about an MU1 demo, folks were telling me demos were not common with this component and people were buying them unheard. I was told this from owners and another dealer (who did say he could try and get me a demo unit).
Since you own a Tambaqui, and I also owned one for a short while, would you say the MU1 simply provides "more" of the Tambaqui sound, or does the MU1 change the Tambaqui's sound, and if so in what way(s)?
I will ask if I can extend the audition. The dealer seemed pretty flexible in that regard.
I'm not going to be too critical about the unit being new, because the dealer ordered the demo unit specifically because I requested a demonstration and they didn't have one in stock. As soon as it arrived, they contacted me and I picked it up.
Otherwise, as I was asking around about an MU1 demo, folks were telling me demos were not common with this component and people were buying them unheard. I was told this from owners and another dealer (who did say he could try and get me a demo unit).
Since you own a Tambaqui, and I also owned one for a short while, would you say the MU1 simply provides "more" of the Tambaqui sound, or does the MU1 change the Tambaqui's sound, and if so in what way(s)?
Good to know that your dealer helped you out. Not sure where you are located, but in the U.S. I could only find one dealer who would provide a demo, although the MU1 was new on the scene then and perhaps that has changed although with the continuing supply issues maybe not.
Interesting question about the Tambaqui. I suppose it both builds upon and thereby changes the presentation. What I can say is that how I listen to music has changed with the addition of the MU1. Not only do I have a greater appreciation for how whole albums are put together (kinds of songs, order of songs, etc.) but also a greater understanding of the musician's individual voice and expression. It isn't about the "sound" per se (or the usual audiophile descriptions) but the whole fabric of the musical story.
There has been a significant increase in the number of albums that I revisit in order to delve deeper into the artistry. Since the Tambaqui is the only DAC I have, I don't know if there is a special chemistry between these two or whether the MU1's influence is as great with other DACs. Reviews seem to say the latter.
At any rate, hope you have the chance to determine if it is right for you. I had a Lampi many, many years ago and enjoyed it. Those were the early days when the models were changing rapidly and the quality control wasn't what it is today. Still, there was an indication that the designer had a good ear for music and finding a way to coax digital to provide musical engagement.
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