Grimm Audio MU1 and MU2 Music Players

[bluebeat]

To my ears there's an improvement too since the latest Roon update. I hear better defined leading edges and a wider and deeper soundstage, overall a more nimble and musical presentation. Nice!

 

Cheers

[Vangelis]

The reviews from the online audio journals have been so consistently over the top, that I had made a leap of faith and ordered a MU2, in the hope of it being a one box solution. As long as MU2 is, at least a lateral move sonically, I will be happy.  I’m an older audiophile and music lover, and no longer a fan of crawling around snakes of cables and cleaning around shelves filled with audio chassises. My goal with the MU2 is to create shelve space, make a more manageable system and get rid of all the spaghetti without compromising the level of audio I have at this point. Hopefully my expectations are not too high.
 

Regarding streamers that I’ve owned in the past, Roon did not sound nearly as good as the manufactures OS. This being said, companies like Taiko and Grimm that are highly regarded only offer Roon for their OS.  I’m missing something, is it a more a matter of implementation or proper set up?
 

I’ve read many of the posts on this thread. One thing that is obvious, Roon set up parameters affect the sound quality. I noticed that Taiko published Roon set up recommendations that applies to their streamers.   Is there a compiled list of Roon settings for Grimm streamers, beyond what I see in the MU2 owners manual?

[Mike123]

“As usual, MU1 tends to minimize the SQ impact of successive Roon builds (compared to many other servers), but that does not mean that it is completely immune to them. Whatever, I'll be making sure that I do have a backup of this build in case the next build goes the wrong way”

 

Agreed! With a myriad of component combinations, Roon wont stand pat. I’ll need some resolve to not update on the next FW. Side point, ordered the MU2 and was surprised at the near glut of MU1’s in used markets (mostly dealers). Conversely,  DAC’s like the DAVE are relatively the same in quantity and price.  

[stevebythebay]

4 hours ago, TheAttorney said:

Maybe they have indeed deployed some magic. Last night, I upgraded from build 1388 to 1392, and felt there were some nice (if subtle) improvements, which is impressive considering I thought 1388 was already pretty good. The main reason for the new build were "performance improvements", with which I didn't have a problem with in the first place, but maybe the Law of Unintended Consequences has applied?

 

As usual, MU1 tends to minimize the SQ impact of successive roon builds (compared to many other servers), but that does not mean that it is completely immune to them. Whatever, I'll be making sure that I do have a backup of this build in case the next build goes the wrong way.

I'm curious. How do you create a backup of an actual "build"?  The backups offered in Roon appear to only capture the database and settings but not the underlying code. Do you have another server with license that you use for just this purpose?

[TheAttorney]

1 hour ago, stevebythebay said:

How do you create a backup of an actual "build"? 

Because each backup includes the build number, I've assumed that the s/w version is also backed up (otherwise how could functionality introduced at each build keep in step?). But it's just an assumption - I could be wrong.

[PYP]

2 hours ago, Vangelis said:

I’ve read many of the posts on this thread. One thing that is obvious, Roon set up parameters affect the sound quality. I noticed that Taiko published Roon set up recommendations that applies to their streamers.   Is there a compiled list of Roon settings for Grimm streamers, beyond what I see in the MU2 owners manual?

Suggest you start with the last on the Taiko list and see how that sounds:  Disable DSP and remove filters.  

 

I don't think there is a posted list for the Grimm, but @TheAttorney has a post or two on this thread about what he has tried (a lot).  

[PYP]

4 hours ago, bluebeat said:

To my ears there's an improvement too since the latest Roon update. I hear better defined leading edges and a wider and deeper soundstage, overall a more nimble and musical presentation. Nice!

 

Cheers

when Roon re-programmed the lefthand menu, the performance was snappier.  Perhaps they have trimmed down some code that affects sound too (network traffic?).  

[stevebythebay]

28 minutes ago, TheAttorney said:

Because each backup includes the build number, I've assumed that the s/w version is also backed up (otherwise how could functionality introduced at each build keep in step?). But it's just an assumption - I could be wrong.

From my reading of responses on the Roon community site, it would appear that the backups do not envelop the software version code with them.  Net: once you've moved forward, you cannot go back.  Classic physics "arrow of time" applies to this software.  I've other hardware that allows for using any number of old firmware.  Yet with Windows systems, complete backups allow for their restoration, no matter their age.  The caveat is you're subject to intermediate malware...

[aangen]

I am really enjoying the sound of the latest version of Roon. I notice some lag when using the program on my iPad. But closing and reopening the app gets things hopping again. The DAC in the MU2 continues to make me really happy to listen. This thing is what the MU1 should have been. Most enjoyable! I believe I may have convinced at least five people to order an MU2. As they arrive the response has been great. So far no one has been anything less than impressed. Whew. It could have just been the placebo effect but others seem pleased.

 

We won’t know for certain that we aren’t fooling ourselves until ASR does its testing. If they don’t like it what will we do?

[TheAttorney]

On 4/7/2024 at 4:10 PM, Vangelis said:

I’ve read many of the posts on this thread. One thing that is obvious, Roon set up parameters affect the sound quality. I noticed that Taiko published Roon set up recommendations that applies to their streamers.   Is there a compiled list of Roon settings for Grimm streamers, beyond what I see in the MU2 owners manual?

Start with my earlier post, further down the page here. The referenced forum is still running strong for dedicated roon tweakers.

[Vangelis]

Wow, there is a lot to absorb on that thread.  This was just what I was looking for. 

Thank you 

[aangen]

I finally have my Grimm MU2 connected directly to my Gryphon Apex Stereo Amplifier. Stealth Audio Sakra V17 LE balanced cables between the MU2 and the Apex. Gryphon Commander Preamp is powered down and out of the system. (Sigh)

 

It sounds really good. Using the volume control on the web control page works well. At the moment I am listening to music I am very familiar with. It sounds clean and clear with a slight boost in the mids. Could be just the track.

 

Does the MU2 used as a preamp negate the need for a Gryphon Commander Preamp? Even if it did I would not say as much. I will say it isn’t suffering. No sir. Very clean, very musical. All of the good things I have come to enjoy from listening to the MU2. Just $66K worth of preamp out of the mix. I could live with this, yes I could. 
 

If you are interested in taking a preamp, server, streamer and DAC out of your system and replacing it with one beautiful box, this is a good way. 
 

I did notice when turning the volume up and down a lot and quickly there is a clicking noise inside the MU2. Relays? I also hear what sound like relays clicking when switching inputs. Not a problem, I just mention it as I hear it.

 

I believe the Preamp function of the MU2 is as wonderful as the reviewers have exclaimed. This is not a surprise. 

[Vangelis]

Anyone upgraded to a SR fuse in the Mu2, if so what value was it?  Not sure if it’s a similar spec as what’s in the Mu1 which think was small / short 640ma fast blow. 

 

[stevebythebay]

16 minutes ago, Vangelis said:

Anyone upgraded to a SR fuse in the Mu2, if so what value was it?  Not sure if it’s a similar spec as what’s in the Mu1 which think was small / short 640ma fast blow. 

 

Might be worthwhile ($) to ask Grimm if there's any possible chance doing so would make any difference.  

[TheAttorney]

13 hours ago, Vangelis said:

Anyone upgraded to a SR fuse in the Mu2, if so what value was it?  Not sure if it’s a similar spec as what’s in the Mu1 which think was small / short 640ma fast blow.

MU2's fuse is a bit higher at 1A.

IMO, the MU1 (and therefore probably the MU2) is affected by power cords, power connectors, power conditioners and fuses in much the same way as all other hifi components that I've tried. I felt the SR Orange (the best I had at the time) gave a nice boost to my MU1 (more obvious, say, than the recently mentioned roon tweaks). It's rated very slightly higher than spec because of SR's reputation for premature failure. My risk.

 

I doubt if Grimm would ever publicly condone audiophile fuses, for the same reason as most other mainstream manufacturers - they are obliged to put safety first, which is fair enough.

[stevebythebay]

3 hours ago, TheAttorney said:

MU2's fuse is a bit higher at 1A.

IMO, the MU1 (and therefore probably the MU2) is affected by power cords, power connectors, power conditioners and fuses in much the same way as all other hifi components that I've tried. I felt the SR Orange (the best I had at the time) gave a nice boost to my MU1 (more obvious, say, than the recently mentioned roon tweaks). It's rated very slightly higher than spec because of SR's reputation for premature failure. My risk.

 

I doubt if Grimm would ever publicly condone audiophile fuses, for the same reason as most other mainstream manufacturers - they are obliged to put safety first, which is fair enough.

What do you currently use in your Grimm today?  What do you mean, exactly, by "a nice boost"?  Can you relate this to sonic qualities?

[Vangelis]

No doubt, manufactures are generally not keen on aftermarket fuses. Some of them are OK with it, like Innous. I’ve experienced significant improvement by upgrading my fuses to the overpriced, but effective Synergitic Research fuse.  

So, is this a 1A slow blow or fast blow in the Grimm. 

[TheAttorney]

1 hour ago, stevebythebay said:

What do you currently use in your Grimm today?  What do you mean, exactly, by "a nice boost"?  Can you relate this to sonic qualities?

I still use the same SR Orange in the MU1 - haven't bothered to change it, but I did add an SR Purple in the UK mains wall plug, which was better still.

 

I don't try to dissect sound into separate characteristics (unless a particular aspect really stands out).

I'd class the fuse upgrade as an incremental, general, across-the-board improvement, very broadly equivalent to going up one level up the hierarchy of any manufacturer's power cord range. Put in another way, a bit more focus and clarity along with a slightly more natural presentation. I always value a change where both clarity and naturalness are improved at the same time -  a sign of a genuine improvement, rather than just a different flavour.

 

MU2's fuse is 1A fast blow worldwide.

[stevebythebay]

1 hour ago, TheAttorney said:

I still use the same SR Orange in the MU1 - haven't bothered to change it, but I did add an SR Purple in the UK mains wall plug, which was better still.

 

I don't try to dissect sound into separate characteristics (unless a particular aspect really stands out).

I'd class the fuse upgrade as an incremental, general, across-the-board improvement, very broadly equivalent to going up one level up the hierarchy of any manufacturer's power cord range. Put in another way, a bit more focus and clarity along with a slightly more natural presentation. I always value a change where both clarity and naturalness are improved at the same time -  a sign of a genuine improvement, rather than just a different flavour.

 

MU2's fuse is 1A fast blow worldwide.

Is that the large (5x20mm) small or large (6.3x32mm) size?

[TheAttorney]

14 hours ago, stevebythebay said:

Is that the large (5x20mm) small or large (6.3x32mm) size?

The small 5x20mm size for MU1. I'm sure MU2 would take the same size.

[Ronnie112]

Hans Beekhuyzen also confirmed the new built of Roon 2.0 is sounding slightly better. On his latest review of the Nucleus, available on Youtube next week (or direct of you have a Patreon membership), just a bit after the 14 minute mark in the video.

[Terrycwk]

Hello, just wondering if the rotary volume clicking sound in the MU2 can be defeated?  Thanks!

[Ronnie112]

I'd guess not. Clearly the sound is from the volume control relays clicking under the rotary disk.

[Terrycwk]

1 hour ago, Ronnie112 said:

I'd guess not. Clearly the sound is from the volume control relays clicking under the rotary disk.

Thanks Ronnie like always!

[krass]

15 hours ago, Terrycwk said:

Hello, just wondering if the rotary volume clicking sound in the MU2 can be defeated?  Thanks!

 

it is the sound of a quality design implementation.… just enjoy it.