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

@nyev You may be alot of things but timid is not one. Few of us mere mortals will purchase three top notch server/streamers for a shootout. Never forget, the fastest depreciation known to man happens to server/streamers and dacs.

 

A few more free pieces of advice, in particular, dac optimization as it pertains to the Grimm MU1. The first of which is….do not buy any dacs right now…you are introducing so many variables with three server/streamers and the various cables that you really do need to see whats going on with your existing setup. As a reminder, you were seeking a simple setup…two boxes. To me, based on my own unscientific experiments, that didnt seem possible to me with the Innuos or N20…it just might though with the Grimm. My recent posts encouraged you to try as many as you like and I implied that you should consider the Grimm after listening to the others in the event they didnt please you. Of those you are trying, the Grimm IMHO may be the only one capable of elevating your inboard Gryphon dac module to a level that you could be satisfied. You wont know until you try but now that it is on the way, you may as well be patient and wait and see. With that caveat…

 

Consider focusing on stand alone dacs which do not automatically upsample. For instance, the Meitner MA3 (which I love enough to have owned two at the same time in two systems) would not be a great fit with the Grimm because the Meitner upsamples everything to dsd regardless of what is input. Others may or may not but do your due diligence. Since a great deal of the magic with the Grimm is due to its clocking and proprietary upsampling techniques I can’t imagine a rational reason for the 24/192 output from the Grimm could be improved upon by that stream being re-upsampled by the dac. 

 

Everyone prefers what they prefer but in my experience I have found the NOS R2R ladder dacs seem to sound most natural to my ears. Some will swear by dsd or higher pcm dac rates, I just havent been inspired by sample rates, only by good sound. Focus on the output stage of the dac….thats where the magic either happens or it doesnt.

 

I also have not tried the spdif/rca/75ohm output from the Grimm, only the AES/EBU output. I have said elsewhere that, if I hadnt already owned a top-shelf dac I might consider some of the better resistor/ladder/or R2R 24/192 stand alone dacs with the Grimm. A couple that come to mind: Aqua or Merason dac1…maybe even a previous gen msb. Might save some money given the dac’s clocking is somewhat moot since the Grimm clock owns the day in this regard.

 

Above all else, I might suggest that you hold off bringing in any dacs until you have the chance to hear the Grimm with your inboard Gryphon dac module. You can then perform back to back to back comparisons. Your next step will likely be to liquidate the 3rd place server/streamer in your shootout, Maybe even the second place as well. I contend that the Grimm has the potential to elevate the performance of well executed dacs which may not have alot of bells and whistles. 

 

With the Jorma aes cable, you will get a better idea of what the N20 and the Grimm can do. Dont be afraid to rotate some other ethernet cables to feed these server/streamers. I can’t stress enough my disdain for the AQ diamond ethernet cable but YMMV. You will find the Grimm to be a little more ethernet, power and AES cable agnostic than others, which I consider a good thing. Also run your ethernet stream “wide open” at its fastest in the event your switch reduces speeds to a steady 100mbps (like ether regen and the like).

 

Best wishes in this next stage of your evaluation….you will find that the Grimm volume control will be your go to…especially since Roon makes it so easy. Unlike most server/streamers and their interface with Roon, the volume control from within Roon is intercepted by the Grimm and controlled by the Grimm for superior resolution. Most others are controlled by Roon and risk bit stripping unless run wide open. Again, not the case with the Grimm.

@ghasley 

What are your impressions of MU1 internal DAC vs external DAC? I believe, I read somewhere that you were using a Total DAC, is that still the case? 

@lalitk 

I do not believe that the Grimm MU1 has an onboard DAC.

@ghasley 

You mentioned the Mearson DAC. Isn't it DS Burr Brown based rather than R2R?

Thanks,

Charles

@ghasley thanks again, and this time I’ve already been thinking along the lines of your advice :)

I admit I still hang onto the dream of being satisfied with my current DAC and staying true to my original objective - which I know is probably unlikely. Even if the Grimm does everything I want and more, you and others have convinced me to try an outboard DAC just to see. For all these reasons I am not planning to buy any DAC(s) at this point. I admit I might have a moment of weakness if a used Holo KTE comes up for a good price. But that aside , not going there at this point.

BUT - One thing that bugs me, in the back of my mind sort of way, is how many thousands of hours my poor Diablo has been run simply breaking in other gear, cables, etc. The Diablo does get quite hot - like a very warm (but not scalding) cup of coffee - due to its small amount of Class A power. For this reason, it DID cross my mind that I might want to buy a very cheap used DAC, simply so I can have the new server circuits running with a connection, so my Diablo can have some rest…. Not sure if this is a silly concern or not!!

 

 

@charles1dad 

Thanks! 
 

@ghasley 

Let me rephrase, what is your experience with an external DAC fed by MU1’s FPGA upsampler vs FPGA upsampler turned off (bypass) ?