Grimm MU1 Streamer - Really "The Best"?

@nyev

Thanks to being made in China. Like the MU1 too.

The Grimm is hand made in the Netherlands, Eindhoven IIRC. Not that there’s anything wrong with Made in China…

@ghasley , thanks for the correction.  I’m not sure why I thought the MU1 was made in China.  

@ghasley

The Grimm is hand made in the Netherlands, Eindhoven IIRC.

Correct.

Charles

@nyev 

Catching up….I see that you’re now open to trying out an external DAC. Which is great and you owe yourself to do so if you want to hear ultimate performance out of ultra high-end streamers. Now that you’ve opened this door, my suggestion would be to let N20 break-in and shift your focus on auditioning DAC’s before buying another streamer. I would only consider buying K50 if you have unlimited funds to simultaneously compare K50, N20, MK3 with your choice of 2 to 3 DAC’s. You know what this would entail, tying up lots of money over a long period of time and patience to access what’s sounds best to your ears. The path to ultimate nirvana also entails multiple boxes and cable web, take a look at my ‘digital’ system under my user ID. I am well on my way to a five boxes digital front end from a once two box pretty darn good digital system (EMM Labs DA2 + N20) 

I can say from experience, finding the right DAC won’t be as easy as snapping your fingers. I went through painful yet equally enjoyable journey of owning 6+ DAC’s over last fours years before I finally found my ultimate DAC. Not to mention so many auditions at dealers and audio shows. Since you only stream, your DAC is the next most important piece of the puzzle after your Integrated. Truth be told, your onboard DAC is going to be a bottle neck for streamers like N20, K50 and Statement. You won’t truly know what these ultra high end streamers are capable of until you pair them with a really good DAC. 

During my DAC journey, Aurender remained my rock. I did hear offerings top offerings from Auralic, Innuos and Lumin but always returned to Aurender. And now I am pursuing Aurender N30SA as the ultimate companion to my DAC. Another huge plus with Aurender is their seamless integration with quite a few ultra high end DAC like MSB, Merging over Ethernet (RAVENNA). With this integration, you can opt to remove USB, AES and SPDIF cabling out of the equation. 

@lalitk , thanks for sharing, and for the advice.

I may be able to get demos of DACs in simultaneously with the next server, and, depending on the value of the DAC, purchase it too. That might be doable with a DAC like the Holo May KTE (although I won’t be able to get a demo of that one - but this is the level of DAC I could purchase alongside the next server).

The DACs mentioned by others above like the Bartok are more expensive, but are combo streaming DACs. So would a lower cost DAC-only, at the level of the Holo, be reasonable to trial? I see Musetec could also be interesting at an even lower price. But these DACs are a lower cost than the cost of my current Gryphon Diablo 300’s DAC module. So do I actually need to go higher? I know cost isn’t the deciding factor in performance but I’m just trying to plan at what level to engage. I can do another server + a Holo level DAC, but not another server plus a Bartok (which I could demo first but would only do so if I could potentially buy).

Also, somewhere above I changed my go-forward approach to require server capabilities. This is because I discovered for the first time that my system has become revealing enough to make the difference in quality matter to me. Once I settle in on a solution, my plan is to build a library of files but limited only to my absolute favorite material. The rest I will stream.

To be clear, I’d still be considering the K50 (or the MU1 despite that the K50 is more flexible) in conjunction with getting some DACs in as demos, at let’s say the $7k level or lower. Might be too limiting at that level?  While I’m unable to get home demos of the servers I’m interested in here, there are a few other dealers who are more demo friendly that I might be able to borrow interesting DACs from.

I can recommend the Musetec as purchase piece, Holo May KTE great choice as well. I've seen both of these compared to much more expensive dacs, held their own or were preferred in some cases. KTE may be highest resolving R2R dac, and the Sabre 9038 pro chips in 005 are extremely revealing, transparent, both are musical dacs to boot. Both excel with usb input, some have used other inputs to good effect. Both of these dacs not out of place with any system at any price.

Thanks @sns. Evaluating that class of DAC, my thought is to go with the MU1 first, despite the emphasis on AES. My thinking is that the MU1 has a reputation for neutrality and precision, and not injecting a strong character of it’s own. While this is counterintuitive, considering I enjoy a mildly richer sound, there are other factors more important to me than this warmth, and I do feel that between the Innuos and the N20, the N20 has a bit of warmth and smoothness to it. The K50 is also known to be fuller sounding. In really isolating the sound of any DAC’s I’m testing, including my current Gryphon DAC, I feel like the MU1 might be best positioned to maximize the precision and neutrality giving me a good baseline to gauge DACs by. Not only in their character, but also by their performance, assuming that the MU1 is as accurate and precise as people (not just reviewers) say it is. The N20 and K50 can remain options if I want to reintroduce a touch of richness to the sound once I get a feel for the DACs.  That’s my current thinking…

I think my most recent thoughts on the N20 in my current system have pretty much stabilized for the near future, knowing that long term use can change things.  While I still think I hear a slight improvement with AES over USB, it’s so close that I wonder if I only hear it because I expect to.  I will get around to subjecting myself to a blind test, but I am expecting not to pass it.  I’ve also gone back and forth a few times with tiny speaker adjustments - my speakers with the N20 really want to be toed in a lot.  Tried backing off on that slightly for a few days, and just went back to the more toed in marker position.  Immediately it was like “ah, that’s a bit better.”
 

Either way, 

Purchased an MU1. Should have in a few weeks.

Next need to consider the DAC. Will try to line up some demos before buying anything, and at the very least see how the MU1 does with my Gryphon DAC just while it’s burning in. Which I’m very interested in, because in theory it will help me get an understanding of the weaknesses of my DAC, supposedly being neutral leaning and accurate. Want to see if I perceive any negatives that might be common to either of the other two servers, which might be attributable to my DAC. Will try to get demo DAC’s in once the MU1 is burned in.

Yes, I do anticipate a revelation when I try the demo DACs - far moreso than I expect with the MU1. But I wanted a really neutral baseline to test the DAC’s with..

So I know, I’m only partially following your wise advice!

I’m also buying a Jorma AES cable finally, now that I found someone who will sell me one. I’ll need to return my demo Audioquest Diamond AES cable this week unfortunately, so I won’t be able to do controlled A/B tests between AES and USB.

Will continue running the AES on my N20 for 4 more days.  Still hoping something changes there, but probably not at this point.  At some level I’m disappointed in that, as I’d hope that fancy clock in the N20 would do something.  Will be interesting to do the same comparison with a different DAC.  On that note, the dealer who lent me the Diamond cable are a Linn and Moon dealer.  They might have some of their lower end DACs on hand for me to try with the Diamond cable.  But they often can’t as they are a tiny outfit and only have two demo systems in their shop, and most of their gear is reserved for that.  I will ask though.

Good luck on this upgrade. Hope it is all you are looking for. 

Well, the MU1 may be all I’m looking for, but maybe not - I have zero expectations in terms of how I’ll enjoy it, and in what configuration. But between three server solutions and TBD DAC’s I’ll be trying eventually, I’m sure I’ll figure it out. I’m not banking on the MU1 being part of the final solution; could be the N20 for all I know at this point! I’m a bit down on Innuos currently - I’m sure just due to my system parameters - super impressed with its detail air and space but not with its lack of image stability and solidity in my current system. Not sure that’s the right way to describe it. Maybe a new DAC would sort that out. Will find out eventually!

@nyev 

Congratulations on your purchase of MU1. This would be another reference point for you on both techs, streaming and DAC. What are you thinking in terms of XLR Interconnects for connectivity between MU1 and Diablo. Looking forward to your feedback. 

Have fun listening to the different streamers in your system. It’s nice to see someone put their money where their mouth is and actually get first-hand listening impressions, at home in a familiar system, rather than armchair quarterback based on reviews, Youtube influencers, "price of parts" and amateur comments etc. (which is fine, as a starting point, the problem is when folks forget how compromised those impressions are...). Show/dealer experience is also far from ideal.

As far as separate DACs go, there are obviously a lot of good options to choose from. I would be wary of folks who strongly push you towards dac x or dac y, especially on this forum. So-and-so DAC is a giant killer, can compete with cost no object DACs, etc etc. With DACs in particular, there seems to be a competitiveness where folks want to validate that their value priced DAC is in the running among the best out there, frankly it’s a little silly and in my experience not based in reality (I have tried some of these flavor of the month DACs out of curiosity and quickly moved on. I’ll just leave it at that). At the risk of leading you to another rabbit hole, the best way to settle on a separate DAC is the same thing you’re doing with the server search...try a bunch in your system and see what you like. Have fun out there.

@lalitk , regarding the XLR interconnects, I have to admit I have no idea where to start there, as my system has not needed anything but USB cables for many years now. 

A mild source of stress of something I’m planning to research later so any pointers on that will help!  Do I need to bother trying a few options of interconnects, or does the fact that they are XLR negate the need for this?  Should I really be looking at ultra-low cost options since they are XLR?

Won’t be getting any DACs to try for quite a while yet.  The MU1 will probably take a month to arrive, and a month to burn in.  So T - 60 days or so until I bring in some  DACs….

Good post @metaldetektor. Selecting a DAC is a process, very similar to selecting Speakers, Integrated (or Pre and Amp) and Streamer/Server for any seriously put together audio system. 

@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) ? 

On the subject of Grimm DACs, no the MU1 has no onboard DAC.  It is in the same class of product as the N20 and K50, but with its FPGA upsampling board.  The other thing that distinguishes it is that currently, it only supports Roon.  But as @ghasley said, the MU1 intercepts things and the usual disadvantages of Roon don’t apply to the MU1.  Grimm have gone to great lengths to do this.

Now, the truly interesting product which is long overdue is the MU2.  I believe it’s about two years late coming out now.  The MU2 will have an onboard DAC.  Not sure if it will finally launch this year. But I have read that MU1 owners expect to have the option to upgrade to a MU2.  I’m not sure how this upgrade works, but sounds good.  Another reason to hold off on purchasing any DACs I suppose.

Other forums report incremental improvements in the MU1’s sound with firmware updates (as has been reported with other servers updates too).  The most recent being the 1.5 update in December.  People report a denser, bigger midrange, however they did report this effect gives the top end less of an edge.  But overall thought it was an improvement.  I don’t like thinner sounding midranges, that’s one reason I like the N20.  Prior to the December firmware release, I read that Grimm had actually overhauled the code that does their onboard upsampling.  I like how they present each firmware update as a labour of love, indicating how long they’ve been working on it will all the value it provides.

In one of their firmware release notes they sadly said that they failed to enable the FM tuner hardware that is on the MU1 with their firmware release, with the resulting sound not being up to Grimm’s standards.  They announced they were giving up on this notion.  I’m thinking this was an April Fools joke, as that particular release was in April.  Either way, funny!

@lalitk

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?

The MU1 doesnt have an internal dac, it is a D to D only via an AES/EBU connection to a dac. Yes, I have a Totaldac D1-Tube-Mk3 which has three dac ladders per channel and a two tube 12au7 output stage. I have played around with the Grimm upsampling at 4fs, 2fs and then disabled. It sounds quite good with each and its really dependent on the recording. For instance, I happen to almost seek out a well recorded 16/44.1 recording over some (I repeat, SOME, not all) higher resoluton versions of a given piece of music. It seems there is something really special when the Grimm gets ahold of a really good 16/44.1 file and runs it through its 4fs upsampling and outputs it to 24/192. Quite special to my ears.

Seriously though, I went through all the right brain, various iterations of the options and I have just left it on 4fs and forget about it. I just listen and enjoy these days.

@charles1dad

Indeed, the Merason utilizes two Burr Brown 1794a dac chips in dual mono. To many ears it competes well with well executed R2r ladder dacs. I mentioned it as a very well built but no frills non-oversampling option with an excellent output stage for very reasonable money. At least it used to be very reasonable money at ~$5k...its now an $8k dac.

@nyev

The Grimm firmware updates are well done, you are correct. I must admit though...I just dont hear "night and day", "a veil has been lifted", "my wife walked into the room and asked what I had changed", "my jaw dropped" kind of comments I read all too often. It just sounds great. BUT....so did the Aurender I demo’d and while the Grimm MU1 clearly outperformed the Innuos Zenith Mk3 that I owned at the time, I was never unhappy with the Innuos. In my system, I appreciate the Grimm remote volume implementation almost as much as some other independent components as my amplification of choice doesnt have a remote volume control.

Some rumors of the MU2 are a little off the mark. I have heard, although unsubstantiated by anyone with good knowledge, that the dac section for the MU2 is (once again, rumor) being contributed to by Bruno Putzey of Mola Mola Tambaqui fame. Evidently they are good friends and have collaborated in the past.

@ghasley 

At least it used to be very reasonable money at ~$5k...its now an $8k dac.

Yikes!!! 
A 60% increase. Resorting to its Switzerland roots it seems.

Charles

@nyev 

I’m a bit down on Innuos currently - I’m sure just due to my system parameters - super impressed with its detail air and space but not with its lack of image stability and solidity in my current system.

When I first got my Innuos Zenith MK3, I had a similar experience. I know someone mentioned the SR Purple fuse earlier and you commented that you wanted to keep the playing field level. However, the SR Purple fuse had such an impact on the sound quality that honestly I was shocked how a mere fuse could do this much. You already gave the advantage to the N20 by playing to its strengths when you tried the AES output. I strongly feel that the Purple fuse is Innuos' key strength. You should at least give it a shot. Plus it's only $200, you can return if it doesn't work for you. In my case, it helped tremendously by providing more stable and vibrant imaging. The increase in soundstage depth and width and the extra vibrancy the fuse provided was not subtle at all.

Secondly, if you are planning to try out dacs within the $7K range, let me be the first to tell you that you will be disappointed. While they might reach the potential of your built-in dac, I seriously doubt you will hear any improvement. A well-designed, well-thought out built-in dac gives the designers several opportunities to fine tune performance which is in line with the overall sound signature they are aiming for. If you're lookin for substantial improvement I strongly feel you have to set your sights on a higher price bracket. Lalitk has the Merging dac which I believe is the real deal. I heard it at his home last year and was very very impressed. 

Lastly, I really appreciate the feedback you are sharing with the audiogon community. There are very few people who compare high-end streamers in their own systems and faithfully report their findings without any bias. I certainly have enjoyed reading your posts and find them very valuable. Thank you for sharing!

@arafiq 

Lastly, I really appreciate the feedback you are sharing with the audiogon community. There are very few people who compare high-end streamers in their own systems and faithfully report their findings without any bias. I certainly have enjoyed reading your posts and find them very valuable. Thank you for sharing!

Agreed!

This is something you’re more likely to find on Whatsbestforum. The effort and time is appreciated.

Charles

@arafiq @charles1dad +1

+1

I have been following this and really enjoy reading about your journey…

@nyev question, maybe I missed it, but have you tried the upsampling on the N20 with the AES output?

@ghasley that is a really, really interesting rumour if true (MU2 being a Mola Mola / Grimm collaboration.  That would be amazing.  Almost seems too cool to be true though, or founded in wishful thinking.  Hopefully not!

@arafiq I will try the Purple fuse with Innuos. Will see how it goes!  As I said I’ve heard from enough people that I expect a big performance jump.  I should clarify something though.  I don’t have any issue whatsoever with the Zenith on its own.  I used to, prior to the 2.0 software update.  Before that update, I slightly preferred my Mac Mini running Audirvana over the Zenith with Roon.  But after 2.0, the Zenith pulled ahead, with Sense and even with Roon using Squeezelite.  My issues only started when I added the PhoenixUSB Reclocker, which I know is much revered.  There is no question it made a world of difference, improving clarity, depth, etc.  But it made all tones, and I believe this is specific to my system, cables, etc, much more “on a knife’s edge”.  It’s not bright.  It’s not thin.  But I find I can’t help but constantly gauge the image delivery quality.  I can’t fully forget about that and just listen to music.  Everything is just not quite delivered with a commanding sense of confidence and solidity.  Not enough impact.  The N20 does this for me, but without the detail air and depth I get with the Innuos setup.  This is simply my experience in my system, I know all of these products are well loved by most.

@nyev

I do realize, you wanna hold off to buying a DAC but these two DAC’s are definitely be in my list of DAC’s to consider, if I was shopping for DAC’s.

Thanks @lalitk. The price of the first one is temptingly lower, and I did say that I wanted a cheaper outboard DAC just so I could burn in the MU1 and cable, without subjecting my Diablo to even more burn-in duty. It’s done enough of that over 4 years! That said, I was thinking of a really cheap DAC with an AES input for this purpose. On the other hand, this could be an opportunity to try an outboard DAC beyond my Diablo and serve burnin-duty as well. And, it would give me something to try for the next 60 days with my Innuos and N20 setups while the MU1 is on its way and burning in. In fact it might be even longer until I have a burned in MU1 due to high demand they are seeing right now. 

@nyev an extra few hundred hours on your Diablo, you are seriously overthinking this. Relax….

@ghasley, yeah, I know….  It’s going strong with the N20 still, constantly, as we speak!  I will stick to waiting things out for the DAC.  But I will add @lalitk ’s suggestions to the list of DACs I will want to try at the right stage.  
 

Means I may not have any updates for quite a while.  But I’ll give the purple fuse a go at least.  

I just read that yes, the MU1 truly does have an FM tuner on board with a connection for the antenna, however it was never enabled through software and presumably abandoned. Not sure if they have since abandoned its useless antenna connector on the rear. @ghasley , maybe you can comment on whether your MU1 includes the antenna connector?

Not that it matters - I just find it SO odd that a product like this includes an FM tuner and antenna connector - just doesn’t seem to belong! The rest of the product seems so singular in its design approach - minimalist, Roon only, etc.  I seriously thought it was an April Fools joke when they announced that they failed to make it work well and had given up!  Even Grimm said in their release notes that it’s an anachronistic feature when there are endless great sounding digital radio stations available.  Funny.

@sc2, I've tried upsampling from Conductor on the N20 only briefly a few times over a few days, and I did not listen too seriously.  May be a correct or incorrect bias, but my understanding is that upsampling from the app/roon/Conductor/etc is not the path to good sound.  My very brief impression was that the sound changed somehow when I engaged upsampling.  I didn't really consider carefully how it changed.  But when I disengaged upsampling again, things suddenly sounded more together and fluid or something.  Not really sure, all I know is it made a slight change, and that I think I liked it best turned off.

@nyev yes, the MU1 was all set to add FM tuner capabilities. I never even considered it when making the decision to purchase. The thing you must understand is the MU1 was intended to be the digital preamp for an active speaker system. The fact that we audio crazies commandeered it for our 2 channel system was a happy accident for Grimm. It has a number of digital inputs AND it also has analog inputs. I havent tried the analog inputs. 

Yes, the Purple fuse elevates the Zenith another level. It actually stopped me from considering the Grimm which I find very intriguing. The sonic gains were large and quite shocking. Music sounds less audiophile and more natural/real. A small bit of glassiness or audiophile exuberance was removed allowing for a more natural and engaging sound. I could easily detect lower noise. I found myself turning it up a bit more as the overall presentation was more at ease.

I compared both the Merason Dac 1 and the La Voce S3 to my Mojo Audio Mystique 3 which I owned at the time. I found the Merason to be wonderful sounding. Very close to the Mojo in all areas except the Mojo offered improved body, muscularity and weight. I would put Mojo Audio on your list to demo.

I was not that impressed with the S3 compared to the Merason and Mojo Audio dacs. It lacked the refinement of the Merason and could not match the realism, muscularity and linearity of the Mojo Audio dac. I guess I found the S3 a tad boring or less engaging than the other dacs. Pleasant sounding, but just missing something.

I have added SR Purple fuses to my Circle Labs integrated and noticed nice sonic gains, but not near the level I experienced with the Zenith 3. I will be trying them in my Tron Electric Signature dac soon. I don’t think the Purple fuses are necessarily a sonic home-run for every piece of gear they are placed, but the impact in the Zenith is special.

Thanks @grannyring.  Question regarding the purple fuse - since I have the PhoenixUSB should I consider trying adding one there as well?  Or only on the Zenith which feeds the PhoenixUSB? In my current system, the PhoenixUSB plays adds air, upper detail, and dimension that is not there with just the Zenith on its own.

I would start with the Zenith first. Good to see what this one move does on its own. SR fuse direction runs S To R when looking at the label. Here are the instructions on fuse placement from the Innuos site:

https://innuos.com/kb/replacing-the-fuse-on-innuos-products/

The S end should face the units interior while the R faces the the exterior/back. Fuse direction is very, very important. The fuse will need 24 hours on it before showing its potential. The first 24 hours is not the time to judge sonics. No need to play music for burn in, just make sure it is on. Get a 5mm x 20mm Slo-blow 3.15A fuse.

Thanks @grannyring.

Hello @nyev ​​​​@lalitk and others!

I have ordered my Grimm MU 1.  It will be paired with my Mola Mola Tambaqui.  I have an Elation KS AES coming as well.  The Grimm will replace my Nucleus + , and I will move my Aries G2.1 to my Makua based system   This is of course if the Grimm sounds better than my Aries with the Sean Jacobs power supply!  I also still plan to use the Muon Pro filter in front of each.  That will again be an interesting test.  Yes, as others have mentioned, the MU2 is interesting.  I had not heard it was a joint venture with Mola Mola…but since I own the Tambaqui already, here we go.

@fastfreight 

Congratulations on your purchase! I expect MU1 to blow away Nucleus +.  It will be interesting to hear your feedback on MU1 vs G2.1. And you picked one of the best AES cable out there to transmit digital bits to Tambaqui or Makua. Keep us posted! 

+1 @lalitk 

Looking forward to the listening impressions.

Charles 

congrats @fastfreight!  You should have a sort of preview of the MU2 if the rumour is true!  But I’m not holding my breath….

I was told by my dealer that the price is going up for the MU1.  He said there was an influx of orders to get in at the old price….  Slightly longer lead time because of it (4 weeks).  @fastfreight just curious - did you hear about this?

@fastfreight 

the MU2 is interesting.  I had not heard it was a joint venture with Mola Mola…but since I own the Tambaqui already, here we go.

The above comment is an unsubstantiated rumor that I posted earlier in the thread. I have nothing official or unofficial…its just a rumor that Elvis shared with me before he left the building LOL.

Congrats! Look forward to your impressions. By the way, I am currently demoing a Network Acoustics Muon AES cable. It has some tough competition as I am presently using a Shunyata Sigma V2 AES/EBU cable.

@nyev what is the new retail price of the MU1?

Ok, I have this observation in regard to MU1, look at this internal photo of Grimm, https://6moons.com/audioreview_articles/grimm/2/. Now compare this to N20,https://www.aurenderamerica.com/products/n20 Aurender looks far more substantive to me, power supply alone seems much substantial.

Now, as far as impact on sound quality, I can only speculate without hearing, but when it comes to choosing equipment for purchase I rely on internal photos in part. I'd be more likely to purchase N20 vs Grimm in this case.

@sns 

Grimm chose to go in the direction of SMPS as the preferred power supply option. For the record, Antipodes has followed suit with their flagship Olandra music server. SMPS rather than linear power supply as found in their K50 server.

“Powered by a twin-PCB switching power supply developed in-house to provide the lowest possible jitter values, the MU1’s core is shaped by a NUC board that runs Linux and the Roon Core server component. Importantly, Grimm does not just rely on standard Linux or Roon packages. Refusing to use standard libraries, the Grimm team wrote their own code from the ground up. This is where the MU1 differs from other music servers and likely an important reason for why it sounds so superb”

From the Hi-Fi Advice review.

Charles

SMPS does seem like it is gaining some traction as a preferred power supply source. I've never heard it in a SOTA configuration, but would like to. You also mention Charles, that Grimm has written all their own code from the ground up. From all I've read, optimized code is one of the big influencers behind top-quality sound. Taiko is current working on XDMS, their proprietary streaming software, and by all accounts of many users on WBF, it has had a very significant impact on sound quality for their Extreme server. These are interesting times for sure.

@sns 

I owned an Innuos Zenith, I demo’d an Aurender (w20) and purchased the Grimm. Everyone should demo multiple streamers and buy what sounds best to them. In the event it is a tossup between two or more, then I guess the tiebreaker for someone could be parts count or weight? Are fewer parts or lower weight considered better or worse?

On the topic of Grimm and DAC pairings…pairing the Grimm with an nos R2R makes for a radically different (and in my mind more natural and engaging) sound. Grimm and totaldac? Home run.

I would not however be scared to pair the Grimm with DACs that do their own sampling or DSD conversion. Grimm and Tambaqui? Fantastic. Grimm and Meitner? Also fantastic (although less of a delta here vs the onboard Meitner renderer which is quite good, as compared with the Tambaqui, which has a so-so internal Ethernet renderer). As always, I speak from direct experience in my own system and not internet screenshots of what parts are under the hood. That said, YMMV.

The theory behind the above, according to Grimm, is that they think their precise clocking and sampling does the heavy lifting, making any digital sampling/conversion done by the DAC more straightforward and therefore less prone to error. That’s just their theory, but I’ve heard it in (my) practice as well.

@nyev of you want a touch more transparency from the n20 my suggestion is to try the furutech ncf gtx(r) outlet with a good upocc silver powercord with furutech nfc plugs on the n20 such as the zenwave psr14. Dave at zenwave will loan your for free email him.