Grimm Audio MU2 "Major Dac"

@PYP The Singxer is a fine bandaid but not a top shelf solution. I used several iterations and they did a fine job when I was handcuffed to USB out but also handcuffed at the time to AES in. Its a great device to convert USB to other spdif formats (AES being the one I relied upon). Im not arguing that Hans B isnt bright and sincere, I’m just saying his reviews in the future utilizing the USB output from either Grimm will be handicapped. Listen for yourself As its easy to compare with a Singxer….connect it and listen back to back with the AES/RCA outputs of the MU1 into your dac. Disbale the fs upsampling out from the MU1 and connect its rca spdif to your dac. Then immediately switch to the MU1 usb to aes output of the Singxer feeding your dac. Sounds pretty good but not in the same league as the MU1 AES output.

Regarding the Muon and Muon Pro filter. I was an ealry user of the Muon when I had an Innuos Zenith. I “believe” i heard a positive difference but the more I reflect on it, I’m just not so sure. I then upgraded to the MU1 and could not discern whether there was any difference. I was then provided with an early version of the Muon Pro System. (I had also inserted a NA Rubicon swith, which is still in my setup although I cant really hear any difference today). I just couldnt hear any difference and believe me please….I LOVE to spend money on audio gear. Believe what we all want to believe….it matters not in the whole scheme of things. Grimm, Antipodes, Aurender, Taiko, et al do a wonderful job advancing the real science behind getting good sound and it certainly does no harm to insert exceptionally made cables and switches. But Hans B using the USB port out of a Grimm to evaluate anything in the future wont inform any gear decision I might contemplate.

Absolutely, MU1‘s magic is via the AES digital out (with clock signal). I also understand that Hans B is currently using the MU2’s USB out with Singxer for DAC review purposes (and luckily he still can use the MU2 to compare with other digital players, using MU2’s digital inputs).

In his reviews he covers a wide range of performance/price levels. At the time stamp ‘Then why sell?’ he explains MU1’s (magic) effect on more modest DAC’s at review (=majority of DAC’s he reviews). I can imagine that it is quite a puzzle to find a good overall balance in his more than 5 test setups/chains.

That said, he only just bought the MU2 and his test setups evolve. So I wouldn’t be surprised that later on other (higher level) D2D converters will be added in his top test setups for future DAC reviews.
 
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Eelco explaining the MU2:

 
Second video explaining the analog side. Guido Tent is the technical director.

 
I’ve had Innuos streamers for year and have always clearly preferred the sound from their Sense app over Roon. Can the MU2 run with a different OS other than Roon. Will Grimm produce their own OS?
 
I’ve had Innuos streamers for year and have always clearly preferred the sound from their Sense app over Roon. Can the MU2 run with a different OS other than Roon. Will Grimm produce their own OS?
Currently Roon is required, but they are developing their own software. I have not seen any estimates of when it will be available.
 
I’ve had Innuos streamers for year and have always clearly preferred the sound from their Sense app over Roon. Can the MU2 run with a different OS other than Roon. Will Grimm produce their own OS?
I too owned Innuos and I too preferred Innuos Sense for sound quality. I'm going to ask you a rhetorical question...since you prefer Sense on your Innuos, what objective data led you to the conclusion that the cause was Roon? Why would that be applicable to how Grimm Audio utilizes Roon? There is an advantage to a manufacturer when they encourage customers to adopt a "closed architecture" application. Innuos does this and DCS does this but has it occurred to you that Grimm may be taking a different path with embracing Roon? HOW a server deals with the processing requirements posed by Roon can make or break the experience.

There is little argument anywhere that Roon's user interface and metadata are the industry's gold standard. So, it might make sense to let Roon do the heavy lifting in those areas and to instead focus on intercepting the audio prior to any degradation...which is what I have been led to believe is what Grimm is doing! Regardless of how Grimm has chosen to interface with Roon, the Grimm/Roon combo is exceptional together. Why is that the case? Taiko uses Roon and yet Taiko has chosen to go with dual cpu's and specialized cooling. I compared the MU1 and my Innuos Zenith (utilizing both Roon and then Sense) and it wasn't close. I have compared the Grimm vs DCS Mosaic on my DAC and...its not really close, although Mosaic does sound better than either Innuos with Roon or Innuos with Sense to my ears.

I actually was planning to buy the Innuos Statement with the power supply updates a couple of years ago but a funny thing happened on the way to the forum...I stumbled across the Grimm. The dealer handled both so it wasnt about access, it was about sound quality. My Grimm MU1 has been rock solid for more than 2 years and I am impressed each day.

So, let's not jump to conclusions that one thing is holding something back, it is system dependent within a certain context. Perhaps Innuos isn't optimizing its interface with Roon? Perhaps Grimm is? Perhaps it has nothing to do with Roon itself...
 
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Will Grimm produce their own OS?
If you mean their own version of something like Sense, I believe that is not planned. But it seems they are modifying their software to accommodate existing software that are alternatives to Roon, like JPLAY.
 
I too owned Innuos and I too preferred Innuos Sense for sound quality. I'm going to ask you a rhetorical question...since you prefer Sense on your Innuos, what objective data led you to the conclusion that the cause was Roon? Why would that be applicable to how Grimm Audio utilizes Roon? There is an advantage to a manufacturer when they encourage customers to adopt a "closed architecture" application. Innuos does this and DCS does this but has it occurred to you that Grimm may be taking a different path with embracing Roon? HOW a server deals with the processing requirements posed by Roon can make or break the experience.

There is little argument anywhere that Roon's user interface and metadata are the industry's gold standard. So, it might make sense to let Roon do the heavy lifting in those areas and to instead focus on intercepting the audio prior to any degradation...which is what I have been led to believe is what Grimm is doing! Regardless of how Grimm has chosen to interface with Roon, the Grimm/Roon combo is exceptional together. Why is that the case? Taiko uses Roon and yet Taiko has chosen to go with dual cpu's and specialized cooling. I compared the MU1 and my Innuos Zenith (utilizing both Roon and then Sense) and it wasn't close. I have compared the Grimm vs DCS Mosaic on my DAC and...its not really close, although Mosaic does sound better than either Innuos with Roon or Innuos with Sense to my ears.

I actually was planning to buy the Innuos Statement with the power supply updates a couple of years ago but a funny thing happened on the way to the forum...I stumbled across the Grimm. The dealer handled both so it wasnt about access, it was about sound quality. My Grimm MU1 has been rock solid for more than 2 years and I am impressed each day.

So, let's not jump to conclusions that one thing is holding something back, it is system dependent within a certain context. Perhaps Innuos isn't optimizing its interface with Roon? Perhaps Grimm is? Perhaps it has nothing to do with Roon itself...
It’s not an baseless assumption that Roon might not have been the best sonic OS for Grimm to use. At this junction, no other OS options can be run with the Grimm servers.

This wasn’t a “jump to conclusion” or an off the cuff observation, especially light of the testimonials from nearly all of the owners of Lumin, Auralic and Innuos and my first hand experiences that Roon clearly doesn’t sound near good, at least in theses products. Now this being said, of course, Grimm as well as Taiko likely have superior Roon implementation, that I have no understanding of, and I’ve heard recent rumblings that Roon has made some resent sonic updates. As in all audio design, its more about the final result than which bits are assembled.
 
It’s not an baseless assumption that Roon might not have been the best sonic OS for Grimm to use. At this junction, no other OS options can be run with the Grimm servers.

This wasn’t a “jump to conclusion” or an off the cuff observation, especially light of the testimonials from nearly all of the owners of Lumin, Auralic and Innuos and my first hand experiences that Roon clearly doesn’t sound near good, at least in theses products. Now this being said, of course, Grimm as well as Taiko likely have superior Roon implementation, that I have no understanding of, and I’ve heard recent rumblings that Roon has made some resent sonic updates. As in all audio design, its more about the final result than which bits are assembled.
I certainly didnt mean to step on any toes…just posting my observations that the best two (3 if you count a brief encounter with the Antipodes Oladra flgship) server/streamers I’ve heard personally both utilized Roon. Perhaps its not that they “settled” for Roon, perhaps they optimized their design for Roon? YYMV.
 
I certainly didnt mean to step on any toes…just posting my observations that the best two (3 if you count a brief encounter with the Antipodes Oladra flgship) server/streamers I’ve heard personally both utilized Roon. Perhaps its not that they “settled” for Roon, perhaps they optimized their design for Roon? YYMV.
All is well, no toes stepped on, I’m just nervous about Roon from my prior history with it. I’m definitely hoping that you are on the right thought line, that Grimm does a special implementation with Roon. My Mu2 should be arriving in several days. I will be happy if Grimm sounds at least sounds as good as the three combined chassis I‘m replacing. The goal is to simplify my system, create shelf space, eliminate three chassis, three power cords and two USB cables!
 
The goal is to simplify my system, create shelf space, eliminate three chassis, three power cords and two USB cables!
plus a headphone output for your buddy, who clearly prefers headphones.
 
Anyone upgraded to a SR fuse in the Mu2, if so what value was it? Not sure if it’s a similar spec as what’s in the Mu1 which think was small / short 640ma fast blow.
 
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Anyone upgraded to a SR fuse in the Mu2, if so what value was it? Not sure if it’s a similar spec as what’s in the Mu1 which think was small / short 640ma fast blow.
ditto...
 
The Mu2 is installed. Over the first 72 hrs it has flipped from good at one listen than not so engaging on the next. I’ve always waited a month to create a final opinion. Most every DAC and streamer Ive owned, required a lot play to fully develop and the Mu2 has the additional analog preamp to break in. At this junction, the Mu2 displays a more up front presentation with bit more texture than my Pulsar, PhoenixUSB, Weiss DAC 204, and Holo Audio Serene combo, but the image density is not as fleshed out or focused at least yet. Definitely there is potential here. I need to run in the Mu2 and work my different shelf and footer options to dial it in.
 
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The Mu2 is installed. Over the first 72 hrs it has flipped from good at one listen than not so engaging on the next. I’ve always waited a month to create a final opinion. Most every DAC and streamer Ive owned, required a lot play to fully develop and the Mu2 has the additional analog preamp to break in. At this junction, the Mu2 displays a more up front presentation with bit more texture than my Pulsar, PhoenixUSB, Weiss DAC 204, and Holo Audio Serene combo, but the image density is not as fleshed out or focused at least yet. Definitely there is potential here. I need to run in the Mu2 and work my different shelf and footer options to dial it in.
Break-in is a really crazy roller coaster ride with this and requires patience but this unit categorically is a chameleon in that it transforms with incredible fidelity to whatever PC, IC, and vibration control it is paired with and the upside is quite astonishing if you take the effort and time to do so. I've found that the highest-performing components always respond to their supporting casts in this type of amplified manner by definition. I'd start with ICs, PCs and VC in that order of magnitude.
 
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Break-in is a really crazy roller coaster ride with this and requires patience but this unit categorically is a chameleon in that it transforms with incredible fidelity to whatever PC, IC, and vibration control it is paired with and the upside is quite astonishing if you take the effort and time to do so. I've found that the highest-performing components always respond to their supporting casts in this type of amplified manner by definition. I'd start with ICs, PCs and VC in that order of magnitude.
how many hours do you think it needs to settle down? Some of the early reports seemed to say it sounded very good right out of the box (and then later started the roller coaster ride). Was that your experience too?

Regarding ICs, PCs and vibration control in that order, that is what I experienced with the MU1 as well. Waiting to demo the MU2 soon (next month probably).
 
Break-in is a really crazy roller coaster ride with this and requires patience but this unit categorically is a chameleon in that it transforms with incredible fidelity to whatever PC, IC, and vibration control it is paired with and the upside is quite astonishing if you take the effort and time to do so. I've found that the highest-performing components always respond to their supporting casts in this type of amplified manner by definition. I'd start with ICs, PCs and VC in that order of magnitude.
I’m at 300hrs. Things are improving, clouds are separating. Next, I will be trying different vibration control shelving, footers and a new switch. Noticed you have an SR switch. I found that placing a Shakti Stone on the SR switch more than doubles its performance, really pretty startling improvement.
 
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I’m at 300hrs. Things are improving, clouds are separating. Next, I will be trying different vibration control shelving, footers and a new switch. Noticed you have an SR switch. I found that placing a Shakti Stone on the SR switch more than doubles its performance, really pretty startling improvement.
Vangelis, thanks for the information there. I upgraded from eero to orbi. Expensive but way more detailed than the eero. This feeds the SR switch which I don't need but it makes everything so much more musical... Will look into that Shakti. Keep us posted on the findings of shelving and footers. I'm going to look into an SR fuse too...Have you noticed it's a good idea to shut the unit down from time to time as well?
 
Vangelis, thanks for the information there. I upgraded from eero to orbi. Expensive but way more detailed than the eero. This feeds the SR switch which I don't need but it makes everything so much more musical... Will look into that Shakti. Keep us posted on the findings of shelving and footers. I'm going to look into an SR fuse too...Have you noticed it's a good idea to shut the unit down from time to time as well?
I have not tried rebooting, will give it a try. I just received my Tempus switch and plan to install it tomorrow. Anyone experiencing break in improvement over days or weeks? I’m at 12 days of music time. I’m waiting for that leap up in performance that generally occurs with digital front ends. I added another Zero db isolation platform which has been very effective with every digital device, and no change. My Symposium HD Roller blocks have been a nearly universal great footer and I’m not hearing my normal bump up here, either. Hmm…
.
 

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How are things sounding now? I have a MU2 coming in with the next batch and should be arriving soon. Sounds like I’m going to be running playlists 24/7 for quite a while.
 

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