Grimm MU1 Streamer - Really "The Best"?


I've recently become interested in the Grimm MU1.  While reviews of top end players from Innuos, Aurender and Antipodes and others are typically all very positive, the tone of the many pro reviews of the Grimm MU1 go far, far beyond, with some reviews resorting to using superlatives and gushing of positive system transformation and not being able to stop listening to material, etc..  HiFi Advice and Steve Huff (actually calls it "magic") have such reviews.

Given the delay in availability of the Innuos Pulsar which I'm told will be better than my current Zenith Mk3 + PhoenixUSB reclocker, I am interested in replacing my streaming setup with a one-box solution that includes a high-precision clock.  The new streamer will continue to feed my Gryphon Diablo 300's DAC module, which I have no interest in replacing.

I'm actually a fan of Innuos, after they improved the sound of my Zenith with firmware updates and after I added their PhoenixUSB reclocker. I appreciate this commitment to improving sound quality which is why I was so interested in the Pulsar.

The trigger for considering an upgrade is not for improved sound, but rather, to solve some issues I have with too many Audioquest power cords coiled and clumped together. I will get to lose one of them and one of my USB cords with a one-box streamer. I've noticed my sound is very sensitive to positioning of my AC cords and find I often need to re-adjust the PC feeding my amp to get proper sounding vocals at center stage.  One of my subs also seems to be picking up AC noise when the crossover is set above 60Hz. The second trigger is simply system simplification, removing one box.  All that said I don't really have any complaints regarding sound, and the PhoenixUSB reclocker truly did improve the sound of my Zenith.

While the Grimm MU1 has it's 4X upsampling up it's sleeve with reviewers absolutely glowing over this feature and it's extreme ability to separate tones to the left, right, front, and back far better than the rest, I don't see that Grimm has gone to any lengths with regard to power supply management in the way other brands do including Innuos. The MU1's ultra-simplistic interior doesn't bug me, but the lack of transformers and power management makes me wonder....

Are there any updates from folks who have directly compared the MU1 vs similarly classed streamers from the competition?  Did you find it to be as revelatory as the pro reviewers found it? And, how does it compare to other streamers with it's 4X upsampling disabled?  Does it sound like it suffers from it's lack of power management?  I do see that the clock should be very good...

 

 

nyev

@thyname , no worries. Will continue sharing; in return I receive great advice or inspiration, as with the recent case of the Muon Pro kit. I will wait a few weeks to go down that road as I am still getting to know the MU1 with the Tambaqui. This setup takes a lot more work as I mentioned with speaker positioning. Just when I think I have it as dialed in as it can be, I mark the floor and make the smallest adjustment, and sometimes it gets worse but I’m still finding some adjustments are still improving things. Managed to improve the focus yet again just a few hours ago by toeing in even more and bringing the speaker’s forward a few millimetres. Can’t recommend Herbie’s Audio Spike Decoupling Sliders enough. They provide an unreasonable boost in scale and separation AND they make speaker adjustments a cinch if you have hard floors. And these adjustments are tiny…. But yeah I have enough to deal with currently but the Muon, and fuses will be the next step after cables.

Thankfully I’ve managed to add these pieces without too much expense - the MU1 just prior to the significant price increase, and the Tambaqui I was able to purchase used for what I think was quite a good price.  And if it all works out (I think it will) I’ll get to eventually sell my three Innuos devices and a power cable and two USB cables.  Would actually like to keep both of the Phoenix devices in case I ever have a use for them, but can’t justify that.

Little late to the party but received a Grimm MU1 a couple days ago to demo. Quite honestly, I’m shocked by the transformation this unit makes to my system. System had NUC for Roon, then my Lumin T2 as my streamer into my Nagra tube dac. The Grimm eliminates the NUC and the Lumin and now I go straight into the Nagra with the Grimm. Using an AES connection.  
 

Pro’s:

  1. much wider soundstage and more “musical”
  2. wow factor improvement on bass especially at lower volumes
  3. midrange and vocals much clearer
  4. Hard to turn off my system. Listened for about 6 hours yesterday

Con’s:

      1.  A little slower than NUC getting to songs

      2.  Will probably end up spending more $ on audio….again

 

 

 

Hi all,  my mu1 is settling in so sweetly with my Tambaqui.  I also have the  Muon Pro System from Network Acoustics.   I have previously taken the Muon in and out of my system and always preferred it.  As @lalitk says, the cables are nice.  The ‘system’ includes their network cable before the filter;  the cable exiting the filter has a fixed attachment.   So I tried the mu1 Tambaqui combo with and without the Muon Pro.  It is better with it.  It is less noticeable than prior to the mu1, but still a noticeable improvement.  And YES @nyev the fact that it is non powered (passive) is very appealing. And my addition of the mu1 eliminates my Nucleus + as the Grimm runs my Roon core. (And eliminates my HDPLEX LPS powering my Nucleus).

+1 on @lalitk ’s suggestion of passive filter. I have the ENO filter which is one step below the Muon and still very happy with the results. It helped remove any lingering digital artifacts in the chain. 

“Would actually like to keep both of the Phoenix devices in case I ever have a use for them”
@nyev

I very much doubt that you would feel the need to keep Phoenix pieces around once you hear Muon Pro Kit. I kinda miss the simplistic (passive) approach and the positive attributes of both Muon and ENO filters. In my case, Muon Pro arrived little too late on the scene otherwise I would have gone for Muon Pro Kit in a heartbeat. I am now deeply vested in another solution to look elsewhere :-)

@nyev

If you’re into classical music, give it a listen to one of my favorite album by Ralph Rousseau - 12 Fantasias for Viola da Gamba. The 12 solo fantasias Telemann is known to have published in 1735, but didn’t get re-discovered until 2015. It is available on Qobuz in high resolution.

@lalitk

Reclocking and filtering are different things with different effects. I‘d argue which works better is by definition highly dependent on circumstances and quality of equipment. Granted the effects of reclocking are much more insidious and depend on high resolution equioment

“Reclocking and filtering are different things with different effects”
@antigrunge2

Indeed they are…I don’t expect you to read all 655 posts or even the last few so I am going to clarify the context of my last post to @nyev for you. It was in reference with two components in digital chain, MU1 (streamer) and Tambaqui (DAC) connected via AES cable. Since I am recommending Muon Pro Ethernet filter ahead of MU1, that pretty much negates the need for PhoenixUSB (reclocker) and PhoenixNet (filter) in the foreseeable future. 

The Phoenix Net is in no small portion a reclocker. In my system I reclock the ethernet with both an Etherregen clocked by Antelope 10m preceded by a LHYaudio Ocxo switch. The effect of both is demonstrable and not achievable by Isolators or filters.

@lalitk 

Your explanation/distinction and rationale is clear (At least to me).

Charles

@charles1dad

Thanks Charles. Every now and then you cross path with someone who is hell bent on proving their point that they miss the big picture 😊

The OP already stated that PhoenixNet is not a good match with MU1 hence my recommendation to try Muon Pro Kit which is universally praised for its simplistic design and positive attributes on lowering the noise floor. 

One note…

There is a lot of talk in this thread and others about the Grimm MU1 working well with the Tambaqui DAC, which I have no doubt that it does.  I’ve been trying out an MU1 in my system, vs the Aurender N20, over the past week with a Chord DAVE.  It meshes VERY well with the DAVE as well.

@rshad0000 , great to hear you are testing the MU1 with the Dave and also testing the N20! Very interesting. Any insights yet on the differences you found between the MU1 and the N20?

While I’ve heard some say Dave can be a tad analytical with some material, I wouldn’t be surprised if that’s not at all the case with the MU1, or the N20 for that matter. My guess is Dave has a touch more detail than the Tambaqui.

As an aside I rearranged my shelf this evening and reorganized my cabling, this time with exceptional care. I really think my system sounds different now, in a good way. I think the mids got better.

I’m not a jazz guy but right now I’m listening to the epic London Brew, a loose modern interpretation of Miles Davis’ classic, and it’s fantastic….

Nyev,

The main differences I hear...  The Aurender N20 is very transparent, dynamic and has quiet backgrounds.   The Grimm is very smooth, yet still dynamic, and adds some really nice texture to the music.   I have to say that I prefer the Aurender Conductor app more because its easier for my family to use when I am not around, but I'm still good with Roon.   Overall, I've been really impressed with the Grimm.   Crazy that the N20 is so large and heavy(power supply and battery) while the Grimm is a much smaller unit and a lot lighter.   

I'm surprised I like the Grimm so much with the Chord Dave.   I actually tried the Chord M-Scaler with the Dave at one point and I just did not prefer the sound for some reason and sold the M-Scaler.   The upscaler on the Grimm, however, I do like.   Great rythym and pace with the Dave and is very synergistic for lack of a better term.    

I'm going to continue to listen and will probably make a decision by the end of this week on whether to keep the Grimm or not.      The extra texture and smoothness the Grimm adds, at least in my system, is pretty addictive.

@rshad0000 , thanks for sharing! Good luck with your decision. I know what you mean about the added texture. In my system at least, the MU1 has more impact and edge to the sound vs the N20, while at the same time being smooth. As an example this gives electric guitars some “sizzle” and makes them come alive more.

One thing I found going back to Roon was that the selection of music it plays after you play your specifically chosen music is fantastic. I find this is best when listening to music that is maybe a bit unusual for my tastes, in those cases Roon has introduced me to some great music I’ve never heard of before.

I’m happy with the Tambaqui but would love to hear the Dave.  Maybe one day I’ll hear a Dave in my system and you will hear a Tambaqui.  

One thing I’m planning on doing when the dust settles is removing the DAC module from my Diablo 300.  I originally installed it myself with the blessing of my Gryphon dealer.  Not sure if it will make a difference, it may not, but digital devices are known to be electrically noisy and it’s possible some of that noise is being fed back into the Diablo’s power supply.  I figure why not try.

With my Innuos Zenith 3 I found the Muon Pro to have more positive sonic impact than the Phoenix which I returned. As I stated many pages ago, the Innuos Zenith benefits from the SR Purple in a very special way. Much more so than other pieces of equipment I have put these fuses in. The Zenith really responds. It is a must do to really evaluate the Zenith 3 as it performs on another level for $195. Not sure the SR Purple fuse will have this level of impact in the Grimm. I doubt it based on my experience.

I know SR has a new Master fuse now. It is said to be more resolving. I feel that much resolution could tip the Zenith into possible listening fatigue over time. The Purple is perfect 😊.


Give the fuse 48 hours of burn in before judging. After just 24 hours your tail with wag with joy! The Muon Pro also needs a week of run in. Network Acoustics says many customers prefer the pigtail end of the filter going to the switch. I preferred the pigtail on my Innuos as an FYI. Try both directions over time and decide for yourself.

Pigtail end on Innuos was more full bodied and meatier. Pigtail on switch was more resolving and lite up. It will come down to personal preferences and system synergy.

@nyev , I love how you are having fun with this hobby and passion. You are really going through the effort of trying pieces for yourself and determining what pieces engage you the most. Wonderful.

 

+1, @grannyring on SR Purple Fuse with Innuos and NA Filter. I have been using a different fuse but case in point, aftermarket fuses does impact the sound favorably in most cases. 

Thanks all for the guidance on the Muon filter and also on fuses.

My dealer said they’d get a quote on the Purple fuse for my Zenith, but I haven’t heard back.  I’ll give them a nudge. 

I’d like to try adding Purple fuses to my Diablo amp, Tambaqui, and even the MU1 as well, eventually.  What is the general guideline for what fuse specs to choose?  I know there is a lot of info on this on the boards already but I also don’t want to be the guy that keeps blowing very expensive fuses (or alternatively damaging my gear)…  I think the MU1 uses a fast-blow fuse.  Does that mean I should pick a fast-blow?  What about the current rating - how much higher should it be than the default fuse installed in the component?

 

I am thinking about getting an MU1 but have a question. I currently have three roon endpoints running in my house, and they are all connected to an NUC roon server. If I install the MU1as a Roon server for my main system, would it be the server for the other two endpoints? Or would I need to maintain the NUC as a second, parallel Roon server?

Nyev,

I agree, I love how Roon pulls up "like" songs and plays them!  

Before my current gear I had a Diablo 300 as well...I loved that integrated amp and I can see how the Grimm work work very well with it.   Enjoy!

@peter_s The Grimm can serve to multiple endpoints. No need (in fact you shouldn't -- it would confuse the computers!) to have a NUC and Grimm on the same network.

@peter_s You can use Grimm as Roon Core and connect multiple endpoints as long as they are on the same network. But you also will be asked to sign off your Nuc or get another Roon license. Obviously this has nothing to do with Grimm but required by Roon. Roon requires a license for each core. So in essence you should be ready to transfer your music to Grimm. 

@lalitk Thank you for the tip, I am ordering the Muon Ethernet cable and filter! I am sure it is going to be an upgrade for my system, if not with 30 day returns, I have nothing to lose.

@nyev I would reach out to respective manufacturers for their recommendations on appropriate fuses to upgrade. In my personal experience, whenever the fuse is part if the main circuit there is an appreciable improvement in sound. I would replace one component at a time and wait for it to settle down before upgrading the next one. 

@grannyring , thanks, I’ve seen that link from Innuos and am clear what to get; I’m more wondering what to try for my other stuff (one at a time though). I can guess it may be hard to get Gryphon to provide a recommendation of a aftermarket fuse for my Diablo amp, as I’m fairly certain they will just say not to do that. Could be the same with Mola Mola and Grimm too.

Great to see this thread generating some awareness of the MU1 and also now the Muon filter too!

I’m planning to switch back to my Innuos gear this weekend, for the sake of comparing and contrasting. I have to say that even if I end up preferring the MU1, which I expect will be the case (pending the expected positive impact of the Purple Fuse on my Zenith which may change things?), my overall opinion of Innuos has only increased, as I now have an understanding of what the three Innuos boxes do very well together. Before, I had no perspective other than the Mac Mini I was using earlier than 2019.

I have a soft spot for Innuos now that I didn’t have before. The sound is wide open, super-relaxed, highly dimensional with upper mids and high frequencies “popping out” holographically, with an emphasis on lower end fullness and upper mids and high frequencies. Altogether it’s a very welcoming and easy to listen to sound. In many ways the MU1 is a bit of the inverse - pace seems faster, more snap and solidity to the sound, more texture, more detail, more clarity, more precision, more focus, and absolutely no bloom. The MU1 is far more “to the point”.  Ultimately through cabling, the Muon filter, and a bit of other tweakery I am aiming to get a bit of the Innuos’ fullness and enveloping dimensionality in the MU1 along side all of its excellent qualities. But we’ll see what that Purple Fuse does with the Innuos Zenith!l Mk3!  As an aside, it occurred to me that how I have described the Innuos sound is similar to how I’ve seen others describe the Antipodes K50.  That makes me very curious as to how the K50 would compare.  But unfortunately I don’t think I’ll get to go that far with this particular journey, as much as I’d like to!  If I had a trusted friend with a K50 I’d offer to swap with the MU1 for a a few weeks.  Sadly I have no such friend with a K50!

In comparison I found the Aurender N20 to be “closed in” sounding on the top end - ultimately I was a bit disappointed in the N20 but that is probably just my system/room/ears. I know a lot of people love the N20. I do recall it had an insane degree of tonal density and saturation which made the sound very tangible, as well as this inky blackness effect which I would compare to the effect of conditioners. So it definitely had some great qualities. I know I may have loved it with the addition of a master clock, as it’s one of the few streamers that have a clock input. But for me it was hard to go down that path when I couldn’t figure out a way to be happy with its “base” sound.

 

 

@grannyring 

Thanks for the insight and observations. The Muon Pro is definitely on my radar.

@grannyring I currently have the Eno AG filter in my system. I think you also owned one before. In your opinion, is the Muon Pro a noticeable upgrade over the original Eno? Nyev, sorry I hope I'm not hijacking your thread :)

I am curious about the digital inputs on the MU1. I have a Cambridge, audio cd transport, which is not a high ranking transport by any means. In my fantasy… If I feed the MU1 digital input from the CD transport, it would be as good as any transport, and I would not need to buy a high end transport. is there any reason to believe that the MU1would be agnostic about CD transports and they would all sound the same? 

Also… in reading the manual for the MU1, I noticed that they state that you must use the variable volume control, and that they recommend not using a fixed volume level. I am interested in how that does not reduce the quality of the digital signal. Can anyone chime in about that?

@peter_s My Grimm dealer believes that the best way to feed the Grimm is a high-end CD transport. Of course that's not the typical use case and would defeat the goal for many folks.

Can't answer definitively, but I'd analogize it to DAC pairings. I've used the Grimm with budget ($1k range) DACs and the Grimm made them sound like $5-7k DACs...but I still prefer the Grimm with the "best" (for my taste) DAC possible.

Hello everyone, the first thing is to congratulate everyone who has participated, this is one of the best posts I have read in this forum. I also have the Innuos Zenith MK3 + Phoenix USB combo, I use the Esoteric K01XD as DAC. I use Roon (mostly) and Sense as streaming software. Not long ago, I did some tests to see the behavior of the sound in Roon, placing a Roon Ready to act as a bridge between my Innuos combo and the Esoteric Dac. From those tests, the conclusion I've come to is that a good streamer bridging can go a long way in SQ quality. The best result was when putting as Roon Ready an Esoteric N05 (previous model) and connected by coaxial to my DAC. For this reason, I have been looking at the options for a good streamer, including the N05, or the Hifi Rose 150, the Metronome DSS 2, and in that order of things I found the Grimm Audio MU1. That is a brand that has caught my attention for its good reputation in synchronization cloks.

That's why I was wondering how the coaxial output of the MU is, if it's as good as AES. The idea of ​​a MU1 would also be due to its SQ quality for removing two devices from the system, which is why I am concerned about the comments about the need to place an ethernet filter/recloker before the Grimm.

@peter_s I do not hear a difference when using fixed vs variable volume on the MU1.  But that said I’ve been using it with the volume control disabled.  I’m going to look up that statement you referenced in the manual - what page/section is it in?

@arafiq

I have owned all three NA Ethernet product ranges and can confidently tell you the Pro delivers much more sonically. I like the ENO products as they certainly improve the sound quality of a streaming front end. The Pro makes the ENO sound a tad dull in comparison. Not that the ENO is dull as it is not. However, the Pro brings a level of resolution, space and realism that is very, very special in my system.

@grannyring Thank you for sharing your perspective. Later this year, I was planning to add either an audiophile-grade network switch to my system or a better passive filter. Eventually, I might end up doing both but wanted to take it slow. Given the positive results I have had from ENO, I’m tempted to put the Muon Pro ahead of the switch ... at least for this year.

BTW, another product that had a positive impact on my system performance was the QSA Red jitter plug/conditioner. I was told that it was a better substitute for a fuse and required less messing around with the equipment. It had a similar affect as the ENO, i.e. it made the system more calm (less digital?) and more listenable for longer periods. It's one of the products where you think the improvement is subtle, but when you remove it from the chain you realize you can't really do without.

I will look into the Muon Pro. Thank you for the recommendation.

I have found the MUON pro sounds better than Eno, and it is a 1GB device vs 100 MB for Eno.   The Eno had issues with one of my streamers but the Muon does not. Rather one of my streamers had issues with the Eno …. The Aries G2.1.

I use fixed volume on the MU1 and the Tambaqui and control volume with my preamp.  Best this way I think.

Post removed 

“I use fixed volume on the MU1 and the Tambaqui and control volume with my preamp.  Best this way I think.”

@fastfreight , that is how I have it configured too.  That said, I tried flipping back and forth between fixed vs variable volume and I couldn’t detect any difference whatsoever.

@jetter I agree they look like some cheap crap from alibaba. I can say the same about fuses also :)

The QSA plug came with a 30-day return privilege. I was fully expecting to send it back if it didn't work. But decided to keep it. Another member, @willgolf tried their plug (I think a higher end model) and was very pleased with the results. 

Anyways, I'm going to shut up now and let nyev focus on the primary topic :)

I believe that NA have mentioned, and maybe in this thread, that they will be releasing a switch in June. Combine that with the Muon Pro and streaming cable  and that should be really good. I say that based on the fact that @grannyring has the now discontinued NA Rubicon switch and had very favorable reviews on it. If I'm wrong, please correct me.

The Rubicon is VERY, VERY good…in some systems, the Muon setups might be redundant .

Pictures here!

Note I plan to do something more elegant about the TV at some point.  Will also be getting floor to ceiling acoustic panels for behind my speakers soon.  If the MU1’s screen looks funny it’s because I’ve not removed the cellophane screen protector yet!

My three Innuos boxes are on the top shelf with my Diablo.  Hard to believe that the single, very lightweight MU1 can replace the three Innuos boxes (and corresponding cables) and at the same time sound even better, at less overall cost….

How important is the quality of the AES cable, for connecting the MU1 to the DAC (which in my case is a Holo May Kitsune Edition)?

@peter_s I found that a high quality aes/ebu cable was a worthwhile investment but it isn’t night and day “a veil was removed and my wife walked in and asked what changed” kind of improvement. It matters but its the last thing to address rather than the first.

@peter_s Agree with @nyev, There is no difference between fixed volume control and using Mu1 volume control.

There is a difference between AES cables that is easy to hear when you go back and forth. But the difference is not as significant as other interconnect cables. I have the Mogami and it sounds good until you try higher end cables. I used the Shunyata Omega extensively and it was clearly superior to the Mogami. I am now trying the Nordost Odin 2. This is better than Shunyata especially the textures and inner detail but more subtle difference. I am going to try the Sablon next.

Fyi, you get the same benefit using the Spdif instead of AES cable. No difference at all (between Nordost Odin 2 Spdif and AES) using 1.5m cable length. I tried my 2.5m SPDIF and immediately found it to be inferior to the AES cable so I think they  sound the same for 1.5-2m and shorter but anything long, the AES cable comes on top.