Grimm MU-1 server review - A new force in digital source?

Low325

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May 2, 2021
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@Gjo thats unfortunate. And definitely not a good experience. Hopefully it all gets sorted out.

@PaulB thanks. That’ll probably be what I do eventually for the initial burn in. I’m just one of those that like to turn off devices.
 

kimurastanley

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Mar 16, 2019
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Please let us know of your experience with the Jorma AES/EBU...
Hi, the Jorma AES sounds transparent and fast with good resolution and little coloration. But I don't feel it is bright.
It is not a warm and voluptuous cable, some people may feel it is on the lean side. And this is what I am looking for.
 

DomA

Member
Mar 29, 2022
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Hi All
I have watched and read the many reviews regarding the MU1 and it does seem to be an amazing digital source.
I think I have read comments regarding the AES/Coaxial S/PDIF output and feeding the DAC of your choice. Do users prefer a NOS DAC fed by the MU1 or are there users out there feeding an UpSampling DAC and getting amazing results?
I would be very interested to know if it makes sense feeding a UpSampling DAC with the MU1 given what the MU1 is already doing (magic) with the digital files it plays?
Many thanks in advance :)
 
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PYP

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Jan 13, 2022
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Hi All
I have watched and read the many reviews regarding the MU1 and it does seem to be an amazing digital source.
I think I have read comments regarding the AES/Coaxial S/PDIF output and feeding the DAC of your choice. Do users prefer a NOS DAC fed by the MU1 or are there users out there feeding an UpSampling DAC and getting amazing results?
I would be very interested to know if it makes sense feeding a UpSampling DAC with the MU1 given what the MU1 is already doing (magic) with the digital files it plays?
Many thanks in advance :)
I have only heard the MU1 with my own DAC, which has "asynchronous upsampling to 3.125MHz/32 bit" according to Mola Mola's website. The combination is very musically engaging and I listen many hours every day to all kinds of music (Roon + Qobuz provides a wide selection). Of course, the only way to find out is with an in-home demo. If you are a Roon user, the MU1 is worth trying.
 
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DomA

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Mar 29, 2022
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I have only heard the MU1 with my own DAC, which has "asynchronous upsampling to 3.125MHz/32 bit" according to Mola Mola's website. The combination is very musically engaging and I listen many hours every day to all kinds of music (Roon + Qobuz provides a wide selection). Of course, the only way to find out is with an in-home demo. If you are a Roon user, the MU1 is worth trying.
Many thanks for the info.
Yes, I would definitely contact the reseller regarding a home demo before I would commit.
I am not a Roon user, I use UPnP (10 years now) and Burmester server/control point for navigation which I love too and gives me everything I need. Going forward, I might give Roon a try and I know at present MU1 works with Roon. Lets see.
 
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PYP

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Low325

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Great story behind the company, philosophy, and transparency of upcoming products. They are no where near trying to boil the ocean. Keep it tight and build forward on their successes.

I do want to try the LS1be with subs. That would really scratch my itch to integrate low frequencies in my shared room.
 
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Low325

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Wow. Tambaqui getting fed from the MU1. Jitter-free digital…it all makes sense! LOL! :D
 
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PYP

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Wow. Tambaqui getting fed from the MU1. Jitter-free digital…it all makes sense! LOL! :D
That is how I understand it (and hear it): once the jitter is low enough you have music. As Eelco Grimm mentions in the interview, Grimm Audio built their own jitter analyzer so that the could actually test the very low jitter.

Hopefully, there is room for further improvement. Just as the case that very, very good Class D has advanced even further (would like to hear/compare some of the latest).

To combine a streamer and DDC is brilliant and convenient. Will be interesting to see how the MU2 (streamer/DDC/DAC) develops.
 

DomA

Member
Mar 29, 2022
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To combine a streamer and DDC is brilliant and convenient. Will be interesting to see how the MU2 (streamer/DDC/DAC) develops
Absolutely. Great interview and you seem to trust their goals and where and why they come from.

I am very interested in the MU2 and from a timing point-of-view might suit me when its out in the real world. Can't wait to see and hear what the experts think.
 
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kimurastanley

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Mar 16, 2019
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New firmware is available



Last but not least, this update brings many improvements to prepare for the next big update that will make the MU1 an official Roon End Point and adds more streaming options.
 
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Low325

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May 2, 2021
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I think the firmware is only available now, at the time of this writing via beta, unless mistaken.
Anxiously awaiting this firmware. MU1 is such a good piece.
 
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Low325

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May 2, 2021
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Went live two days ago. Installed it following the instructions without any problem.
Alright then, I stand corrected!
Early Christmas for sure!
 

aangen

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Dec 10, 2020
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www.weirdenergy.com
Issues here. It installed easily enough. It doesn't work very well. Long breaks between tracks, many starting 7 seconds or more into the song. Bah. Reboot didn't help. New mouse cable perhaps? I am sad.
 

Low325

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May 2, 2021
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Not good to hear @aangen
As far as I can tell mine update just fine, all functioning and I cannot tell of any usability issues.

I wonder if there is a way to downgrade to 1.4.X if necessary
 
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Gjo

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Aug 22, 2021
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Issues here. It installed easily enough. It doesn't work very well. Long breaks between tracks, many starting 7 seconds or more into the song. Bah. Reboot didn't help. New mouse cable perhaps? I am sad.
The new-in-the-box MU1 I had for audition would "play" a Roon track for seven seconds, then skip to the next track, and the issue would repeat endlessly. "Play" in quotes because there would be no sound from the MU1 during those seven seconds.

In contrast, my other streamers played Roon without problem during the same time period, so it wasn't a problem with my network.

I don't know what firmware version was installed in the MU1, but I assume it was whatever was current at the time.

I told the dealer, LA Pro Audio, I would be interested in another audition when the problem was resolved, and I never heard back. This was two months ago. It was a very disappointing experience.
 

PYP

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Jan 13, 2022
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The new-in-the-box MU1 I had for audition would "play" a Roon track for seven seconds, then skip to the next track, and the issue would repeat endlessly. "Play" in quotes because there would be no sound from the MU1 during those seven seconds.

In contrast, my other streamers played Roon without problem during the same time period, so it wasn't a problem with my network.

I don't know what firmware version was installed in the MU1, but I assume it was whatever was current at the time.

I told the dealer, LA Pro Audio, I would be interested in another audition when the problem was resolved, and I never heard back. This was two months ago. It was a very disappointing experience.
https://analogaudio-mn.com/ provided an in-home demo for me and are very familiar with MU1 (assuming you are in the US). Hopefully, Paul has a unit available.
 
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fast.freight

Active Member
Jul 30, 2022
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My Grimm MU1 is much more stable than my Nucleus+. rarely a hiccup, and then usually with 2 or 3 or 4 zones active.
Love the combo of MU1 and tambaqui. Experimenting tonight with stock and SR Master fuse in my power supply for my M12 gold switch (Sean Jacobs AR6).
 
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Low325

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May 2, 2021
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MU1 is incredibly stable. Still loving this combo. I tried experimenting with different power cables to the MU1 and it’s quite difficult for me to search for any changes.

Also on the subject of the Tambaqui, I started using it on the default 6V output and to my amp. I was dutifully thinking 2V output over single ended was the de facto standard. Hell to the nah…! Tying back the MU1 I also ticked the 3db headroom option and man the combo is just exquisite
 
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