Grimm MU1 Streamer - Really "The Best"?

I want to use it as both. 
a core to all my zones and a streamer to one of my zones.

Is this a good plan?

Still trying to figure out how the Tambaqui can be this revealing and “musical” at the same time. I think its secret is in how transients are presented.  While the transients are so, so quick (finally my system matches the transient response I adore with headphones), the real trick is how stunningly gentle they are.  Gentle is the wrong word because there is great impact as well.  But there is no sudden edge to the transients, while at the same time still being well defined.

I’m enjoying the Tambaqui to the extent that I wish I had an excuse, to sell the Tambaqui and buy a Mola Mola Makua Pre-amp with the Tambaqui module installed.  I’ve seen some people report the Tambaqui performing even better as a pre-amp add-on module, vs as a stand-alone.  If somehow it were possible to just use my Diablo as a power amp for now I might actually have considered this!  Just for the purposes of a future upgrade path for my amp.  More fantastical musings.  

Either my Tambaqui is improving or I’m warming up to it more, but it sounds more lush and inviting than yesterday.  My interim cheap AQ Red Dawn interconnects are burning in too I guess.

@nyev

If somehow it were possible to just use my Diablo as a power amp for now I might actually have considered this!

I assume I am not mentioning anything you already don't know and you probably have already read the following which I happen to come across in he What’s Best Forum.  If I understand correctly they are discussing Diablo 300 software updates and running the Diablo as an amp only.

Gryphon Diablo 300 - 5.5 years of ownership | What’s Best Audio and Video Forum. The Best High End Audio Forum on the planet! (whatsbestforum.com)

@nyev I think I mentioned before that you will have to spend ~$10K or more (retail) to hear a substantial improvement over the built-in DAC. It would have been a shocker had the Tambaqui not performed at a higher level than the built-in DAC at more than twice the price :)

If you peruse these forums, you come across folks who question spending anything more than a couple of grands on a DAC. You know the "bits are bits, all DACs handle ones and zeroes and jitter the same way, yada yada ... " crowd. People make these kinds of 'carved in stone' assertions without every trying a high quality dac in their systems. It is educational and refreshing to hear about someone trying a high end dac and be able to articulate what they're hearing as well as you are. 

I'm waiting for you to share your impressions once you get the Grimm streamer. The trio of Grimm, Tambaqui, and Gryphon is going to be one helluva system. Color me envious :)

@jetter thanks and I wasn’t aware you could actually use the Diablo as a power amplifier. But my thought of buying a Mola Mola Makua preamp and using the Diablo 300 as a pure power amp was more of a fantastical musing after being so impressed by Mola Mola’s Tambaqui.

@arafiq yes you were right. I really didn’t know what to expect with the Tambaqui, despite its price tag. I’ve seen in other posts that a few can find this DAC to be lean and analytical. While I certainly don’t like lean and analytical and at times have struggled with that side of things in prior iterations of my system, that is not in the slightest what I get with the Tambaqui. Maybe I did detect a bit of that on the first day, but after settling in it became lush and inviting. Obviously system synergy is playing a major role. But I think I “won the lottery” from the perspective of system matching. I feel like the trio of the PhoenixNET, Diablo and Tambaqui (and yes, Innuos Zenith and PhoenixUSB too) are so unbelievably dialled into the precise sound that I’ve been chasing all these years. Total spacial precision and clarity but solid, tangible, rhythmic, propulsive, muscular, fast yet totally unforced, the best dynamics I’ve heard on my system, all while having an incredible smooth flow of music. And a word I don’t often see in reviews: pretty. Can’t put my finger on it but some music just sounds pretty to me, for the first time. The bass has become stronger and even more resolute over the past two days. That’s a good subjective word for how I would describe the sound - resolute. I lot of this I was unknowingly searching for in my random testing of stuff. Blind squirrel found a nut.

Last year I made a TON of upgrades after selling my car to fund everything, and while performance when through the roof I think I felt that ever elusive musical engagement was still lacking. The Tambaqui has utterly closed this gap in my system.

I’ve had long term plans to eventually add a turntable to my system (my Diablo has a phono card) but I now feel like I will be disappointed on that front if I don’t spend an unreasonable amount to get to the level of performance and musical engagement I’m getting now, and the chances I will get there with the right voicing for me seems slim…. This sound is not just good (it is), but more importantly I just can’t get over how it simply ticks all my boxes for my personal tastes so perfectly.

Of course there are even higher end DAC’s which I was curious about (CH Precision aNR EMM Labs DA1) but I’m not so keen to even look at these anymore.

The one thing that I’ll repeat as a ding against the Tambaqui is it seems to have slightly less breath, air and space between everything, and maybe some other DACs might present a bigger, grander and richer sound than the Tambaqui’s more focused approach. But its resolute solidity and precision while still being utterly revealing is well worth the trade off for me, as I get more musical enjoyment at the slight expense of HiFi spatial pyrotechnics and overall scale, which possibly, for me, may even be attributes that get in the way of the music to some extent..

I spent last night playing all sorts of albums I love that for decades have sounded like crap on my system, being thin/harsh or bad recordings. For the first time every single one of them sounded great on my system with the full extent of the musical content clearly coming through without any unpleasant aspects. My system became more revealing AND harsh recordings have become highly enjoyable. So cool!

Update: Just remembered my criticism of the lack of space and air may be entirely related to the $300 AQ Red River balanced interconnects I’m using, which I’ve read are decent but known to clobber spatial distances. So the Shunyata cables should help with this when they arrive, as should the MU1’s 4X oversampling. But really, I’m not feeling I’m missing anything at all right now.  Pretty sure I’ve never felt that way about my system before, ever, in the decades I’ve been at it.

@nyev 

When does the Grimm and your Shunyata interconnects arrive?

@ghasley should have both next week, however I need to travel for work and will be gone most of the week which is terrible.  And my wife said she will NOT set everything up to commence burn-in while I’m on the road….

Well, since you are already married you will have to let that slide LOL. Breakin for the Grimm is only a few day and Shunyata’s newwer cables are minimal as well. Looking forward to you achieving your goals.

Waiting for the “I didn’t think it could get better but then I added the Grimm and new ICs” follow up :-)

Over the past two nights I’ve noticed sound with the Tambaqui to be significantly clearer with greater dynamics and more dimensionality at night, after midnight. Which is typical for most people I know, but the difference between day and night has become a bit more noticeable with the Tambaqui I think. My theory on why this is, is either the Tambaqui has greater headroom in terms of performance so with clean power the boost is more noticeable, or, that the Tambaqui is particularly sensitive to dirtier power. Certainly don’t see those big transformers in the small Tambaqui that larger DACs have.

I had this issue in my system before and the solution was to upgrade everything to the extent things sounded acceptable during the day. And the Tambaqui still sounds great in the day. But late night listening spoils me a bit.

Unfortunately I have found that while conditioners do reduce noise, the relative difference between day and night remains, as both day and night get better. That said I find conditioners adversely affect tonal balance and as such I went with a Torus RM20 isolation transformer instead. Which also reduces noise but without impacting balance, and not resolving the day/night difference (day/night improves equally so gap remains).

I’ve concluded there is no solution short of what I’ve read that some audiophiles have done: at their expense, convince their power company to upgrade the city transformer feeding their house. That’s not happening!

I agree and also purchased the same Torus isolation transformer from Bryston Bit-20.  However, as my system evolved and became better the day/night conundrum dissipated.  Biggest change in a decade has been SR fuses, now with a mix of blue and purple which made EAR equipment which was relegated to back-up status now the stars of my electronics.

@fleschler glad to hear the day-night problem went always for you as your system improved. For me it was the opposite. As my system started to become more revealing the problem emerged. And yes the problem was diminished as I further upgraded from there. But now with the Tambaqui DAC I do find that at least for 5-6 hours a day, its exceptional performance with soundstage, dynamics and clarity collapse more than maybe my other DAC’s do during those hours. The Tambaqui can sound a touch more congested than the others when the lower is bad, with dinner time being the worst. But then again, the Tambaqui also does better in these areas than my other DACs do when the power is “clean”.

Still trying to make sense of this!  @fleschler did you notice any components you upgraded in particular that helped the most with the issue?

@nyev what power cord are you using on your Tambaqui?

@nyev  Yes, in my prior home where night and day differences were quite obvious and distressing, the installation of Synergistic Research power outlets and fuses diminished the problem.  It could be that providing superior equipment power is the key.  I already had a dedicated audio only power panel which I implemented in my new home.  My new home also has superior acoustic isolation and enhanced sound distribution.  After 1am, the sound may sound better but I'm unsure because the equipment has already been on for an hour or more and may just have warmed up to maximum sound quality.  At a minimum, I listen every night from 12 am to 2 am.  

I know where you're coming from because 15 years ago there were stark differences in diurnal listening, especially between 6pm and 8pm when people got home and put on their A/C, tvs, microwaves, etc. negatively effected the grid..  

@fastfreight , I am using an Audioquest Hurricane for all my source equipment.  One of these Hurricanes is the old braided style and definitely doesn’t sound as good as the others.  I keep this one on the PhoenixNET.  Once I get things sorted gear-wise, I do plan to upgrade my cords.  They are also 3m cords which is not practical (long story).  

 

@fleschler I did upgrade my house’s AC circuits to address the issue last time (along with component upgrades).  Dedicated 20A AC circuits using 10AWG wire, all audio gear on the same phase, Shunyata receptacles, etc.  I don’t have a dedicated breaker panel for my system however.

I really need to get around to the Synergistic fuse upgrades though; everyone seems to say how much of a lift they add.  Do you have specialty circuit breakers in your panel as well?

@nyev  I don't have specialty breakers but as you, everything is connected on one 20 amp breaker with 3 more available throughout the room if I need.  Without the SR blue fuse in the EAR 864, I would dump it.  80% of my CDs sounded adequate to mediocre with the glass fuse and LPs were good but not great.  Acme's coated fuse was quite good too but did not have the fullness of sound of the blue fuse.  The EAR 890 has an SR purple fuse.  The orange did not do much for me.  The glass fuse was okay but the purple fuse exploded the soundstage and separation of instruments.  Greater dynamics and 3D soundstage compared to glass.  Did not try an Acme fuse.  

I've been using boutique (SR brand) fuses in amps and pre-amps for almost 15 years.  So substantial that my cable manufacturing friend who hates tweaks, upon hearing the SR black fuses compared to stock glass and ceramic in my tube monoblock amps, did one better and installed circuit breakers in place of fuses in his amps.  

In my prior home, I did not connect my CD player into the isolation transformer as it sounded better directly into the wall.  With separates now, I connect my CD transport directly into the wall which sounds better.  

@fleschler , thank you, I will hold out hope that experimenting with the SR fuses will at least help with the day/night swings in quality.  This has actually been on my audio to-do list for a while now.

@ghasley ​​@metaldetektor ​​​@svenjosh , can either of you tell me if the MU1 comes with a generic AES cable as an accessory?

My MU1 is scheduled to arrive on Monday but I don’t yet have any ETA on my Shunyata cables and I have no other AES cable currently. The prior AQ Diamond cable I was testing the N20 with was a loaner.

If the MU1 doesn’t come with any generic cable I will buy a cheap one so the MU1 including the AES / 4X OS circuit can be burning in while I’m travelling for work Tues through Friday this week.

@nyev mine did not come with one when I bought last year. Do you have a rca/spdif cable? 

Do you have a SPDIF cable? A new Grimm will sound good with that as well. No aes included.

@metaldetektor , thanks for confirming.  No SPDIF either.  I will pick up the cheapest AES cable I can find.  Don’t care if it sounds good or bad; really just to have it fully set up and burned in (mostly) by the time I’m home on the weekend.  With any luck the Shunyata cables will also have arrived by then.

To me it just doesn’t make sense to put a $10K streamer in front of a $4,500 DAC

That's what I thought too. So I proceeded to upgrade my DAC - Lampi, BA LABO, Linn Klimax, Weiss 501, Pasithea, Bartok, and finally the Mola Tambaqui. With the Mola and its built-in streamer I felt like I was settled for awhile.

[note: I found it confusing that the Mola distributor STRONGLY recommended adding a $6K Auralic server/streamer + a $3K USB cable! The Tambaqui is $14K!! WTF? Why?? It kept niggling at me... ]

Then I got curious about clocks and jitter. Down the rabbit hole of Master Clocks, cascading clocks, USB to AES Clocks, ad nauseum. Oh, and more cables (bnc, 110ohm AES, USB, etc. etc.).

Early mid-2022 I began noticing increasing media coverage of the MU1. Since playing with all my clocks convinced me that there was significant upside on the streamer side of things [note: Now I get it!] I decided to demo the Grimm unit. Paul, my dealer, told me to forget all my clocking paraphernalia - take it all out of the system and just play the MU1 through the Tambaqui - period.

Well I purchased the unit (anyone looking for a clock?). I won't describe the sound except to say all my streaming music sounds very "analog" and I no longer really care what the resolution of a recording is. That alone frees my mind to focus more on... The Music.

Adding the MU1 cleaned up bunches PC's, IC's, ancillary boxes, AND MY ROON Nucleus+, returning my system closer to that "straight wire with gain" (well, figuratively speaking).

That the MU1 has ROON incorporated is pretty important (and often overlooked) , as Grimm has (with Roon approval) modified the Roon hardware/software to interface and integrate seemlessly with the MU1. In addition to optimizing communication this also serves to eliminate multiple boxes & cables. Let's remember too -  the Nucleus+ with 2tb is $4K.

So now I think I'm settled for awhile. 

I was at the Audiofest show In Toronto Canada a few months ago & by far & away the best sounding server, in at least 2 rooms, was the latest Baetis Reference series.  It sounded like music in a way nothing else did.  I did not run into Grimm server so cannot speculate on that comparison, but not listening to a Baetis server if you're in the market for something of extraordinary audio quality, is a complete non starter. Especially since if you buy it direct from them, they'll upgrade less expensive models to close to the reference level, for a lot less.

“Baetis Reference series.  It sounded like music in a way nothing else did.”

@john1 

What other servers you have heard and compared to draw that conclusion? 

“To me it just doesn’t make sense to put a $10K streamer in front of a $4,500 DAC”

@davespencer , I do get how rationally this may seem unbalanced, pairing a DAC module in an amp to a far more expensive streamer. But in practice I can totally see how this could make sense. The Gryphon Diablo 300 DAC module is absolutely up there with the Tambaqui performance wise, it’s really the nuances in transparency and tone that I’m picking up with the Tambaqui that makes all the difference. I do think it is likely the MU1 will lift my Diablo DAC module and I’m looking forward to testing that configuration despite the fact that I’m really enjoying the Tambaqui.

I agree with you on the multi-box thing. I’m sure that approach yields amazing benefits but thinking about all those cables you were listing, that is not a small cost. If you are at the point where you are out to buy the endgame level of every component and have the funds for the cabling, I can see that making sense. But if not, going for top-tier but fewer boxes makes sense I think.  IF the MU1 and my Diablo DAC module are enough for me, an AQ Dragon cord would be an elegant addition to a minimalist system approach. Certainly couldn’t afford Dragons for an endless number of boxes.  And I really find going up the power cord chain on digital equipment makes a really big difference.

I still have not ruled out the possibility that the MU1 could lift my Diablo DAC module and that I may end up selling the Tambaqui, although I think the chances are small. The Diablo DAC module has a charm with its bolder, “front row” presentation, but not one I’d pick over the Tambaqui. But just maybe, when combined with the MU1 some of the DAC module’s weaknesses will be mitigated. Looking forward to finding out.

Also I should re-emphasize how much I enjoyed the Merason DAC1. Which today I’ve sold for about what I paid for it. That DAC is one that I could get sentimentally attached to, for both the sound and the way it looks. Really is a special product. Listened to it a final time last night and while it doesn’t resolve as much as the Tambaqui, it’s sound is really pleasing to listen to. Quiet, clean, smooth, rhythmic with an inviting sound. I can imagine people describing it’s sound as “analog”, unlike the Tambaqui which I would say is digital without the associated flaws. Another case where a far more expensive streamer could elevate it.

@nyev, sorry I just saw your question. There is no generic cable that came with my Grimm mu1. I am using a borrowed (from friend) Shunyata Omega AES cable.I am also going to try then Sablon and Nordost.

Hello all, My Grimm MU1 arrives tomorrow and will run my roon core and stream directly over AES to my Tambaqui.  Since I have another nice system on my network, a MM Makua with onboard Tambaqui, this system will  receiving streaming over LAN connection.  I am sure from what I have heard the main AES connection to my Tambaqui will be awesome.   I can't wait to try it!  but will the Grimm improve my second (LAN connected) system?  It has been mentioned that the Grimm has less processing power to run Core than my Nucleus+.

So I can move my hot rodded Aries G2.1 to my second system...

I reached out to Grimm:

Dear Ken,

Thank you for checking out the MU1!

To answer most of your questions: yes, the MU1 will replace the Nucleus, no problem. It has similar functionality. Important is to use it for your main system via its AES outputs, but I read you already knew that.

There will be very little to no advantage of the MU1 over the Nucleus for your Zone 2 system since it is just a Roon core with a nice power supply for that.

The Certified Roon End Point function of the next software update (due in quite a few months...) will add little functionality. Only customers with huge databases (> 30000 albums or so) will need a more powerful computer for the Roon Core and they will benefit. If you like to use a second MU1 in your system, you can stream to it without problems. For the track information to become visible however you need to wait until the MU1 has become a Certified Roon End Point.

Please enjoy the MU1!

Kind regards,

Eelco Grimm

So the option of a MU1 as streamer only will come with a software update!

@svenjosh , can’t wait to hear of your testing of the Sablon and Nordost AES cables vs the Shunyata AES!  I ended up buying the Shunyata Omega AES (hasn’t arrived yet), after first trying to find a Jorma cable.  If there is any way for you to try a Jorma I suggest  adding it to try alongside the Sablon and Nordost.  Like the Omega and Sablon, the Jorma seems to be mentioned a lot in pro reviews and in forums and is apparently good with the MU1 and K50.  But I just couldn’t find one!  Very interested in Sablon and Nordost though!

@fastfreight we receive our MU1’s on the same day…. What AES cable are you using?

Hard to find for unfortunate reasons, but the black cat tron AES is very much worth trying, if you can find one.

Received my MU1 (still no AES cable though).  Powered it up and configured Roon.  However, I'm not able to access the internal 2 TB drive to load files.  Also, the instructions say that I'm to add sdb1 to the Roon storage folder (per my serial number as directed by the manual, and because there is no HEAP found), however when I go to the mnt folder per the instructions, there is no sdb1 listed (I see sda1, sda2, sda3 only). 

Also, when I go to the IP address in Windows File Explorer, it takes me to the Roondata folder which is password protected, and not a Music folder like the instructions indicate.

Am I doing something wrong?  Or is there something wrong where it's not finding the hard drive?

I won't be able to troubleshoot until the weekend unfortunately, as I'll be travelling the rest of the week!  @fastfreight I'd be interested in your experience!  @svenjosh , I believe you had a demo unit but if your serial number is higher than 13.0.002.XXX then the process should be the same as with my unit.

Fed Ex is not my friend.

...should come today.

@nyev

Did you reach out to MU1 support team or your dealer to troubleshoot? Do they provide remote tech support like Aurender?

@lalitk yes I’ve reached out and from what I’ve seen in other forums yes they provide tech support.  But unfortunately right now I’m sitting on a plane and will be gone for the week unfortunately.

@nyev 

Safe travels! I bet you can’t wait to get back and start listening to music and your amazing system. 

@lalitk thank you and you are right; can’t wait to get back!  I do have a hunch something is wrong with my MU1 however.  It’s pretty clear in the manual I should see the hard drive on my home network, and it’s not there.  Grimm have a FAQ on their site with this issue and resolution posted and I followed their directions to no avail.  The only indication that there is an optional hard drive at all is on the cardboard packaging.
 

I’ve read others say that they’ve been given detailed directions on replacing hard drives themselves (to increase capacity etc), so hopefully that means there is no scenario where I need to ship the unit anywhere!

@nyev I don’t have a windows computer or laptop. I only have Mac. I can see Grimm in my shared folder and it’s just drag and drop. Sorry that you are having trouble. If you have a Mac, maybe it will see your internal drive. Hopefully you can solve the issue without having to send back.

I am sure you have tried but if you check your Grimm mu1 and get the host name and IP address, you can manually find the hard drive.

@svenjosh yes my kids have a Mac so I can try that when I get back home this weekend. But I really think something is wrong with the drive not being recognized by the MU1 at all, as it doesn’t show up like it says it should as sdb1 in the mnt folder in Roon’s storage settings. So the two issues together point to an issue I suspect.

I’m totally comfortable working inside and messing with the drive or replacing it if I need to. But will wait for direction from Grimm of course. I should hopefully hear back before end of week.

As I said the only sign there is an optional internal drive is that it says there is one on the label on the packaging. I almost wonder if they forgot to install it!

@svenjosh (or others), when you navigate in a browser using the MU1 IP address (or use your phone to scan the QR code on the MU1 screen), do you see any reference at all to the internal hard drive?  I don’t, here or anywhere else on the MU1, menu screens. It’s a bit odd they wouldn’t at least show the drive and it’s capacity status.

There is no reference to internal drive on the Mu1 anywhere (that I could find). Yes I do see my internal drive on my Mac. 

Feature request for a software update I suppose. Not an essential feature but something that would have helped me identify if the drive was actually being recognized by the MU1. Also as a convenience to monitor capacity. I only really care about sound quality so I wouldn’t dock points for this, but Innuos and Aurender have more polished and robust software for sure. Another thing I noticed was just how incredibly light the MU1 is compared to my Zenith. Maybe because it’s missing a hard drive lol…. Again not a criticism (unless they actually forgot to install the hard drive….) as all I care about is how it sounds.

I noticed on the website they state conclusively right in the features list that they will provide an alternative to Roon. That will be very interesting when it happens as I would expect there is a good chance it may sound even better. But not everything Grimm says will happen does happen. Like their plan to enable FM radio capabilities. Bet a lot of people were like “but that’s the reason I bought it!”. Funny that they made a world class high precision streamer/server with low jitter and sophisticated 4X OS hardware and software but they were like nope, too hard, we give up!…. when it came to enabling the FM tuner.

@nyev, have you ever entertained the idea of a music server/player like this? https://www.hifi-advice.com/blog/review/digital-reviews/network-player-reviews/antipodes-k50-music-server/

@nyev I hope it’s a minor issue and you will sort out everything easily after you are back from work. You can actually see your drive and capacity etc on the network. So I don’t think it’s an issue if everything works as it should. 
FM tuners are tough since most radio stations are going the streaming route. So unless you live in a region with high quality FM stations, it’s not going to be very useful. Even then, not sure how long before streaming takes over. 
I also hate to break the bubble, Grimm is not developing an alternative to Roon according to an interview in early 2022. I am hoping they change their mind on this or at the very least give a third party alternative to Roon. Euphony Stylus will be an amazing option. 
 

@svenjosh , I was being a bit sarcastic about Grimm abandoning plans to enable FM tuner, I’m not sure anyone at all cares and I certainly do not :)

I didn’t actually think the chances were very high that they would be developing proprietary player software (although I had hoped). I think the chances may still be good that they add something like Squeeze or MPD support. I even this would be massively valued by their audience for any SQ improvements that might realize.

In re-reading Grimm’s statement on the website, I am pretty sure I had misinterpreted their statement:

“For customers who prefer to only run a simple playback system without Roon’s extras, we will offer a solid alternative.”

I think this simply means they are suggesting the MU1 as an alternative to other servers/streamers.  Not that they are developing an alternative to Roon, unfortunately!

@adasdad , yes I carefully considered the K50 vs the MU1. I went with the MU1 because 1) The general consensus is that it favours neutrality and precision over fullness and richness, 2) I liked the concept of it’s 4X OS and how much people like it, and 3) the MU1 was cheaper and was just about to increase in price by $2500 USD.

I think I was maybe biased towards “neutral, transparent and precise” after my experience with the N20 (which could have been just in the context of my system of course).

If you scan the Grimm bar code with your phone, or manually plug in the address in a browser, you’ll get to an overview page. There you can see how much hard drive space remains and or if the hard drive is being recognized.

@metaldetektor , thanks, but did both of those things and there is no reference to any hard disk on the overview page. But then again @svenjosh doesn’t see any hard drive info on that page either but has no issue accessing his MU1 folder on the disk from his Mac (not via the MU1’s web interface but rather through the Mac’s Sharing utility).

Pretty sure something isn’t right with my MU1 but I doubt it will be hard to resolve once Grimm gets back to me. I had asked them a question prior to my purchase and they took a few days before responding. So I will be patient.