Grimm MU2 Experience

There is another forum that starts with audio and ends with style that has an extensive thread on the Grimm. 

Thanks, I will check it out.   

Doesn't appear to be much available about break-in and what to expect.  Another forum which starts with What's had a thread which mentions rather extended break-in with it.

I’ve had my MU2 for about 3 weeks. All I can say it’s the best digital that I’ve personally owned and I’ve had quite a few top performers including Lampy, Dave/Mscaler, Bricasti, Innuos, Spectral CDP. All the industry reviews are pretty accurate…..you can listen for hour after hour without any listener fatigue ( which I’m sensitive to) and not question what your rig is doing right or wrong…….you just become engaged with the music.

Thanks very much for your feedback.  My unit is scheduled to ship from the Netherlands early next week.  I must say that I am excited but nervous at the same time.  I did hear the unit briefly at Axpona, but it was really difficult to draw any meaningful conclusions.  I will say that it sounds different and it may take some getting used to.  I have heard some stories from users about some break in being over 300 hours.  Others have said that after about a week it really starts sounding like it is getting there.  What has been your experience with break-in?

I didn’t even bother listening to it seriously the first day. After the initial 24 hours it sounded pretty darn good to me. It continued to improve modestly over the next few weeks. 

Looking forward to it, now.  Thanks for your experience.

Jealous of you guys as I can’t swing the Mu2 right now. I upgraded my front end with a T+A Dac 200 for now. Long term goal is a Mu2 with a pair of quality mono blocks. 
I heard the MU2 at Axpona with a LTA integrated and can’t remember the speakers. Very underwhelming but I don’t think the amp and speakers were a good match. Too many respected audiophiles rave about the Mu2 and are replacing 30k in seperates. 
@audio_nirvana  are you using a pre amp? What’s the rest of your system?

@benzman Zellaton speakers.  I agree.  It was not a well matched system.  

@wlp3 So, have you received your MU2 and can you share your experience?

@yowser I received the unit on Saturday.  Unfortunately, I have a terrible ground loop that has precluded any listening. 

Actually, I was concerned that the unit was damaged in transit, but I have just concluded that it is a ground loop and not damage.  I have never had any issues with ground loops or hum with the system, thus my concern that it might be damage.  I have a Trafomatic Rhapsody 300B parallel single ended amp and when the MU2 is plugged in as soon as the ICs are connected I get the hum.  Short term I am using a cheater plug on my amp, but I need a more permanent solution.  I have ordered a turntable ground wire which I will attach to the ground lug on the back of the amplifier and connect it to the chassis of the MU2 to see if that takes care of the issue.  I have the MU2, the amp, and the power supply unit for my field coil speakers on separate outlets but on the same circuit. Would prefer not to use a power strip.

Any wisdom on ground loops would be welcomed.

From what I have heard behind the horrible 60Hz hum, sounded pretty amazing.  Voices are very lifelike and the soundstaging is very precise.  I am looking forward to beginning to listen.  I am running the system 24/7 on a playlist in Roon with the amp off.  Sounds pretty good right now, but i am expecting it go get weird for the first 7 days and then start to improve through 200-300 hours.

@wlp3 Sorry to hear that you have a ground loop when the MU2 is placed in your system!  I did a quick search on the forum and it appears that it's not all that uncommon.  I'm sure you'll get it figured out, but at least the cheater plug gets you by for now.  I have a MU2 being delivered today and is the reason I inquired as to your experience to date.  Glad to hear that it's sounding amazing right out of the box and likely to get even better after running it in.

@yowser Congratulations on the MU2.  I have had a chance to listen a little bit yesterday (20 hours), and I must say that even as green as it is you can tell that it is going to be very special.  Let me know your initial reaction to the sound.

I have the MU1 and I'm considering the MU2.  But haven't experienced one yet.  

Jerry

@yowser Any preliminary impressions?  My Roon over the weekend was painfully slow sometimes buffering for >1 minute and hanging up.  Are you having that issue?

My early impression mimics yours and the multitude of the reviews out there.  Vocals are lifelike as you said, just as the music in general is more lifelike.  I remember one reviewer likened it to opening a window.  It sounded great right out of the box and continued to improve over the last 100 hours.  I've had it playing 24/7 with playlists and Radio Paradise, then listening in the evenings for 1-2 hours.  I'm impressed with the micro details in the music without being analytical.  I'm always a little skeptical of reviews, but they were so overwhelmingly positive on the MU2 that I had to listen in my home and I'm glad I did.  In answering your question, I did not have any buffering issues over the weekend.  As to your ground loop issue, I noticed on the last paragraph of page 7 of the supplied manual that Grimm states the MU2 "relies on safety earth in the mains cable to guarantee your safety. It also needs this connection as low impedance path for mains leakage current to prevent hum or sound quality degradation" and suggests consulting an electrician.

For those of you that have the MU2 how's it going?  I have a MU1/Weiss 501 DAC combo and love 'em. I don't know but image the streamer part of the MU2 is much the same as the MU2?  How to sort that one?  Am considering the MU2 in my other system that will replace a Lumin X1 (nothing to kick out of bed for eating crackers). Nothing beats the Grimm's 2x and 4x oversampling.

I have an integrated (KWM-88 MK2 Integrated Amplifier using KT170's )  I very much like but (the itch) was considering just using the MU2 as the pre into AGD The Audion MkIII Monoblocks or other monos.  I like separates but.......???????

you may want to check out a 432 Evo Master

the master has been compared next to the Grimm and found to sound as good with greater speed and clarity while being just as organic as the Grimm

ps://hifi.nl/artikel/30271/Review-432-EVO-Master-music-server-a-strong-challenger-in-the-top-segment.html

Unprecedented realism

Because at the same time, a phenomenom happens which I can best describe as “de-hasting”. The Grimm also masters this, but the 432 EVO Master even goes a little bit further. With “de-hasting” I mean the feeling that you get as listener with music, to even process very complex passages. With some, and mainly less performing products, the music can become overly bloated and prominent in certain areas, and the music is almost forced onto you. None of that with this Belgian music server who continues to act like a gallant gentlemen.

Even though the price is downright hefty, and a small minus is the fact that it only support USB connections towards a DAC, what we have here is a very special music server which within it’s price class, is among the best challengers today. Even though a top class CD transport still sounds substantially different in it’s own way and still is hard to beat on it’s own strong aspects, there is indeed a far-reaching analog sound. This makes the rendering smooth, airy, spacious and naturally realistic and moreover, also has exactly that right outlined and catchy character that is so typical of a good analog source. Nice work Frederic!

Dave and Troy

audio Intellect

432evo dealers

Just got my MU2 and I’m noticing clicking between tracks on Roon. I know the rotary volume dial clicks, but I hear that same kind of click between different tracks while I’m playing my Tidal playlists. Anyone encounter this, audible clicking between streaming tracks? I am running the MU2 and fixed volume to my preamplifier.

Secondly I’m having a really rough go of it with Roon. I can’t say that I’m a fan. I’m completely stifled as to how to link my NAS and be able to access my stored music, this seems to be a shared issue with people’s posts on the internet. I'm laughing reading that a previous MU2 owner ditched it because of Roon and all these UI issu that really have me head scratching as I read forums in bewilderment. Roon is not the egalitarian streaming I thought it would be.

Also I’m having issues just trying to figure out how to store music on my 8TB MU2. I haven’t connected an external hard drive yet, but it seems to defeat the purpose of my NAS since I can’t link up with it, and add folders.

I have a 8TB unit but I’m having some reservations about storing all my music on it because everything just seems a little stodgy and and unintuitive. The purpose of getting this unit was to be able to still rip CDs with my now Innuos Mini, and then be able to access them on my MU2 through NAS. This process seems to be very involved and techie which is a real turn off, thankfully I’ve already ripped my CDs to my Innuos statement but I really feel that transferring it over all of the edited tracks and album artwork is going to be a mess and future CD storage will be a "process".

Innuos is definitely more straightforward and user friendly and as for sound quality I know it’s not apples to apples but I’m comparing a Innuos Statement with mola mola tambaqui (MMT) up against the MU2. So early on at this point I don’t know how much of the statement that I’m hearing in the sound versus the MMT itself.

The MU2 upon early listening has amazing clarity and ease, in a very good way, but most of my listening is at low volume and I haven’t done anything above 65db. None the less this level of detail that is absolutely without any harshness or digital sheen is impressive. This a a audiophiles neutral DAC delight and side by side to the MMT this will be overtly noted as more detailed, but maybe more forward and linear (to my ears). I do feel as far as size and depth of soundstage the MMT and statement present things in a different way that is more holographic, but I do immediately notice that some things seem recessed or even muddled with the MMT and statement (high praises MU2!). But I would agree with people who have said that the MMT may be a more romantic and expressive DAC (which is weird to say that about the MMT).

The MU2 is it impressive, and should everything come together where it can be a Roon server with ample storage and have everything working smoothly yes this is an amazing one box system. But I am going to go out on a limb here and agree with Bill Parrish GTT audio who said that separates will yield you a better sound, but obviously at a higher cost.

I’m keeping my MMT and MU2, I have two higher end systems, and this was more of an exercise and replacing my Innuos statement, however I do not feel that the overall experience will be just that "a replacement" of Innuos (which I love). Luckily an Innuos unit could be had in the SSD ZenMini S version which I picked up fully well realizing I would not abandon Innuos or CD ripping. I know in US does have a experimental Innuous running Roon setting which I have yet to try, but then again maybe I should?

Again this is very early on in my impressions and there are many kinks that need to be worked out and features that need to be refined and learned on my end. As a side note I do feel the MU2 screen is a little less than useful along with web based Grim app, and the overall ergonomics of this spinning dial to be somewhat less than what I expected.

My system is all shunyata power cables and tellurium black interconnects, and my Ethernet is etherRegen, to Fiber, to cybershaft clock to MU2.

Yamaha C5000 pre, Luxman M10X Monoblocks, dual D12 perlisten subs, Focal Sopra 3.

I’ll be sure to post again with my further thoughts and experiences, obviously everyone elses input is welcomed and appreciated

Linking NAS to Roon

@ja_kub_sz

I have a MU1. As. A newbie I had a few hickups (me more than the unit) and reached out to Grimm in Amsterdam and they and their US guy in California were very helpful. Now that I’m fluid operating is easy. Even big knob on top is simple but it’s seldom used.

MU2 manual is online and details how to load files to internal SD. Did this w/ my files and then sold Roon Nucleus. (Kept HD w/ tracks for s backup but don’t need or use.)

432 Evo Master may be great but pimping it here turned me off. 

@ja_kub_sz 

Forgot to add. My wife loves the big knob on top. She presses it once to stop the music. She used to nuke the tube Amp. 

Can the 432 Evo Master do that? 

Me myself and I
Aduio numskull

PO Box Bong Anytown USA

I wish my wife loved the big knob a little more often.

Kyle and Stan

Go Fund Yourself 

South Park Solicitor 

With respect to ground loop,  try a standard Cat 6 if you are using Cat7 or 8 from your switch to the Grimm.  The metal casing of the 7 and 8 plug can cause noise or hum in some set ups

@ja_kub_sz   I would encourage you to experiment with the device control vs fixed volume setting in Roon.  I have found a significant difference between the 2 settings.  I have found the fixed volume setting in Roon along with the volume fixed at +0.0Db in the MU2 to be best in my system.  The fixed volume setting in Roon offers a wider deeper and more engaging experience in my system .  Of course YMMV.  Also need to note that it seemed to take quite a period of time for the unit to break in and sound its best.  I have had it in my system for about 2.5 months I think it really just seemed to really blossom lately.  FWIW

@wlp3

As of now I’ve only run the MU2 at fixed volume through the web settings for the MU2 and haven’t (so I think) done fixed volume in Roon. Why per say is the "Roon" fixed volume better (technically speaking)? Secondly can you have the MU2 through it’s web setting be at fixed volume, and then again set the Roon-MU2 interface to "fixed" also and get the same result?

When you say "fixed 0.0db" is that the actually checked box in the MU2 we’d control setting for fixed volume? Or is that just the volume dial of the MU2 turned to that setting on the unit? Doesn’t the MU2 display screen revert to 42db in fixed volume via the web interface for the MU2? Again I sit far away from the unit, but I thought I kept seeing that on the MU2 while walking up to it.

@ja_kub_sz   In addition to the volume control on the MU2 there is a setting for Fixed Volume or Device Volume in Roon.  This is accessed by the volume control icon to the right side of the music selection window on the bottom of the screen.  Select the gear icon on the menu.  Under Audio Device window hit the Device Setup.  Under the Volume Control drop down you can select DSC Volume, Fixed Volume or Device Volume.  Device Volume will communicate volume instructions to and from the MU2.  The Fixed Volume control will send a fixed signal to the MU2.  Volume can still be controlled in the MU2.  I am using an integrated amp, so I am using the fixed volume (line out) setting on the MU2, and I have selected +0.0 db as the level of signal output to the amp, and controlling the volume with my integrated amp.  Alternatively, you could set the volume on your pre-amp or integrated to a set level and use the volume control on the MU2 to control volume.  Although the gain on the MU2 goes to +8.0 dB, Grimm advises that there may be some distortion on the higher gain settings, so +0.0 dB is the recommended maximum setting on the MU2 which when Device Volume is selected equates to 92 in Roon.  On my system, using the Device Volume setting in Roon produces a more forward presentation but very detailed.  The Fixed volume setting in Roon on my system produces a wider and a bit less forward presentation but still preserves the incredible detail that the MU2 produces but with a more natural and engaging sound to my ears.  I have been flipping back and forth between the 2 settings.  I do like the Device Volume but it is more HIFI sounding on my system than the fixed volume.  Give it a try on your system.  I am not sure why there is a difference between the 2 settings but there certainly is on my system.  I am running a Trafomatic Rhapsody integrated amp and Wolf Von Langa Ultima 12739 speaker.

@wlp3 

Awesome, thank you so much for that advice. Like I said I'm very new to Roon, and every little suggestion helps. 

Absolutely love your combination of amplifier and speakers, that is such a well made pairing, I can only imagine how good that setup sounds.

@ja_kub_sz   Thank you.  Give it whirl on your system and see what you think.  You may prefer the Device Volume setting in Roon on your system.  On my system, the WVL speakers are so revealing and transparent that the Device Volume setting seems a bit etched to my ear, and the Fixed Volume setting is more natural sounding.  Again, YMMV.  

I must say that the MU2 has taken my system from excellent before to ethereal now.

I must say that the MU2 has taken my system from excellent before to ethereal now

I must say with the MU2 mid-range is the key element that jumps out to me with ethereal precision, accuracy and fluidity. That’s where the magic is and that’s where the bulk of music is happening.

@ja_kub_sz The MU2 just keeps getting better and it has taken 2.5 months for it to really blossom on my system.  I think you will find that bass and hf will get even better with time as well.