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

@fastfreight , @sdl4 there is a cable difference for sure, which I have thought about. I am temporarily using a very low end Cardas AES cable on the MU1 (the old green Cardas AES cable, not the current one. With my Innuos setup I have Audioquest Diamond USB cables. I did try swapping out the Diamond USB cables with generic USB cables and I still noticed the same tonal differences between Innuos and the MU1 (but the Innuos sound became inferior in other ways).

@sdl4 I agree it’s likely that both have fairly neutral measured frequency responses. Our ears are very sensitive to tiny changes in tonal balance which has a massive impact on how we perceive a piece of equipment. Maybe “smooth” is not as good as “relaxed” to describe what I perceive with Innuos vs the MU1. Because it’s all relative, the bass, upper mids and high frequencies “pop out” in a very pleasing way with Innuos, and the upper end detail is so easy to hear. Again, and the expense of the “meatier” tones of the midrange which are not as easy to hear with detail. Because of this, I think that things like electric guitars sound smoother with less texture and detail in the body of the tone. Of note this difference in tonal balance is the most profound of the differences I hear between Innuos and Grimm. The next biggest difference is the more gentle delivery of Innuos vs the more propulsive and energetic presentation of the MU1.  And lastly the smallest difference I hear is the bit of added texture, focus and detail that the MU1 offers over my Innuos setup.  But these last differences are far smaller than I originally had thought as I was getting them conflated with the tonal balance differences at first.

@lalitk , cool you met Eelco! Since he’s referenced this thread to me I would have asked him if sales of MU1’s are up because of it, just out of curiosity! You should also have asked him about the details of the next firmware release - I think you in particular would be very interested in the major new features than are coming. Eelco asked me not to share these details online since it’s still possible these features may have issues in testing.

 

“I have Nordost Odin2 for the rest of my system”

@svenjosh in that case I’m pretty sure I know which AES cable will win your shootout :)

Nevertheless, let us know how your testing with the Sablon and Jorma go!

The 1.5m minimum for digital cables is supposedly required to account for something to do with the synchronization between source and destination.  At least with USB cables, if you look it up you’ll find people talk about “reflections”.  I’ve not attempted to understand it; I’ve just noted the really big improvement when you go from a 1m USB to 1.5m or 2m.  Mark at Sablon told me he had heard this too.

@rc22 +1

At the risk of overstating the matter, I pretty much think you’ve not really heard what the Zenith can do until you have put a the Purple fuse in.  For context, I added the purple fuse a couple of months after adding an ENO filter and EE 8switch with a Supracat ethernet connecting the two.

Your setup is very similar to what mine used to be a few months ago. I was using Supra8, Eno (still have it) in conjunction with Zenith MK3 and purple fuse. I tried the 8switch but didn't notice any improvement so ended up returning it. I think it's downright criminal to own an Innuos streamer and not pair it with the purple fuse. Just like you, I was amazed the level of improvement a 'mere' fuse brought to the Zenith. Incredible!

@lalitk convinced me to replace the Supra8 with the Linkup cable (https://www.amazon.com/LINKUP-Ethernet-Screened-2000Mhz-Structure/dp/B07VVFC1XZ?ref_=ast_sto_dp&th=1). It took about 100 hours to burn-in but it was a noticeable improvement in sound quality. It's very cost effective and worth trying. 

Yes, that LinkUp 8 cable is quite the value. I've been using it since 2021 and it is awesome, better than Supra Cat8 in my system. Another thing to consider, is after you've played the cable for that hundred hours, reverse the direction to listen for less quality or better quality sound. I know the Supra Cat8 was sensitive to it and it was quite easy to hear. Lalit is doing a great job spreading the word!

Just bought a LinkUp Ethernet cable because at that price, why not….  Will see how it compares with my Audioquest Diamond cable which costs more than 10X more…

I spent a couple of hours this Saturday testing the effect of Herbie’s Audio Lab Tenderfeet with the MU1.  I find these don’t work well with all components, but when they work, they REALLY work…  More separation, cleaner vocals, more coherent high frequencies.  But the thing I find you have to be careful of, is that while they almost add positive benefits, sometimes they also can take away something from a particular component.

With the MU1 I’m confident that the benefit of Herbie’s Tenderfeet is unequivocally an all-positive tweak - and a big one too.  With my Tambaqui, I think they are not so good.  I think the sound becomes a bit less muscular and loses some of its charm.  The Tambaqui doesn’t even have feet of its own, just two metal rails on the left and right sides.

With Herbie’s Tenderfeet I find you must be very careful to place them under your gear very evenly, and a bit of experimentation is needed in the optimal placement to get the best degree of transparency.  It’s crazy that even moving the Tenderfeet just half an inch changes the presentation.