Grimm Audio MU1 and MU2 Music Players

[Evo1668]

After reading this thread, I am really looking forward to this coming weekend - as have an MU1 coming to visit so I can listen to the pairing with my D&D 8C’s.  Will also try it into a Vega 2.1 DAC which I have on loan and finally compare against a Linn KDS 3 (Katalyst) 

[Evo1668]

Well after an extended home listening session to several dac/streamer combinations   All streams connected to ethernet through an Ether Regen switch with an Afterdark Emperor OXCO Clock   1. the Aries 2 into Vega 2.1 to 8C - (great synergy, music came alive, goosebump moments, wow! - I was so very nearly tempted.) 2. The Linn analogue into D&D 8C and 2a. as analogue pass through to the Vega - (tons of emotional depth but irritatingly so laid back at times when compared to the Aries/Vega combination, I was horizontal) 3. The Grimm into the Vega - (showed such great promise but somehow felt constrained/wrong - I preferred the Aries/Vega combination and to be honest I was disappointed with the results from the Grimm to the point I was leaning positively to the Aries/Vega. Maybe it was as a result of the permanently engaged filters on the Vega not letting the Grimm shine?) 4. Grimm AES direct to the D&D 8C (that gut instinct, eureka moment when everything just sounds as it should, the hidden details you've not heard before, dynamic range, the soundstage rendered in the most micro of details, and oh the emotional connection it was just absolutely staggering at times bringing tears to the eyes. Tried NOS sounded fantastic but 2FS was definitely better, 4FS not working with the 96K board on the D&D.  Although I believe that new 8C's have a 192K board, so should work with 4FS )   1 and 2 were using a Nucleus + 3 and 4 using Roon core inside the MU1   Tracks used in no particular order were as follows:-
The rest is history as they say, and the Grimm has found a very new happy home - it really is like you have purchased a completely new music collection along with the MU1.  I can honestly say I have never heard Roon sound so UPNP like.

 

[Evo1668]

After well over six months of having the Grimm, the sonics have changed.  It still makes me smile each day, hearing new things, phrasing, dynamics etc.. within familiar tracks.  More than six months on and It sonically never ceases to surprise me in a good way I might add.

 

Now for those that may have a tendency to scratch that itch with regards to their audio equipment purchases - I have not really had that itch .  My network has remained the same, I already was using an Uptone switch with femto clock before I brought the MU1 and was just not in the mood to start tinkering there. I may still yet connect a standard switch and listen.  Power Cables I've tried replacing the stock Grimm one with some PS Audio mains cables - yuk! that didn't last long the stock Grimm cable remained.  I have also tried plugging the MU1 into a PS Audio PP Premier conditioner, instead of straight into the wall socket.  I don't know, but each time there is a certain magic which is lost going through the Power Plant, the music becomes how can I put it? sterile.  But hang on.....  One area I did find a noticeable improvement of unveiling further and that sonic magic remaining, was plugging the MU1 into an old BT isolation transformer I had lying around - I think you can pick these beasts up directly from BT for £30 - £50 these things are heavy but the footprint is quite small around 6 inch cube (they are old mains isolation equipment,  that were once used in their telecoms exchanges.)

 

The other area I have succumbed to the itch is around footers that the MU1 sits on.  I have tried Stillpoints, HRS footers, finite elemente ceraballs - and whilst the sound definitely changed/improved? each time that sonic magic was lost.  Then one day when I was moving the MU1, I noticed that the actual feet on the MU1 have a certain tiny amount of 'give' to them acting like a micro form of suspension for the chassis.  If you press on the corner of the MU1 whilst looking at the base you can indeed see a tiny amount of movement.  At first I thought it was just a very soft rubber on the base of the feet, but if you look face on at the foot itself, you will see the rubber insert is not completely flat, but is raised in the middle across 2/3rds the foot length and there is a definite spring action beneath the centre section of the foot.

 

That got me thinking again (dangerous I know) as I had heard in the past about Townshend Isolation Pods, but I never thought they were something that would/could make a difference under digital equipment, analogue maybe, but never digital.  So to cut a long story short, I brought a set of 4 of the 'AA' size pods ( they are sized according to the weight of the equipment you place on them).  In effect your equipment floats on its own suspension.  Heres a link to how they work http://www.townshendaudio.com/hi-fi-home-cinema-equipment-vibration-isolation/seismic-isolation-pods/  Now don't take my word for it, but the difference they make is not subtle - you keep all the Grimm sonic magic and some - the music plays and sounds louder, but when you go out of the room it sounds quiet in comparison, there is even more dynamics and with an effortless ease you hear even further into the mix.  And don't get me started on what happens to the bass......but if any MU1 owners do try these Townshend Isolation pods under the MU1, you will be very pleasantly surprised. 

 

One caveat - my music - my system - my room - my ears.  Your results may be different, but I doubt it.

[Evo1668]

28 minutes ago, TheAttorney said:

 

Interesting. Where did you position these footers? Directly under the stock footers, or directly connected to the underplate?

And did you try 3 or 4 footers?

I tried multiple configurations of 3 and 4 footers at different positions under the stock footers and baseplate.  With the iso pods, I kept coming back to placing them under the stock footers.  I think the position of the existing footer is integral to the sonic design. Also bear in mind the MU1 has most of its weight over the rear and rear left corner.  Rear left Iso Pod and rear right (adjust in pairs) needing most adjustment to level the MU1 when using the Pods.  Each time 4 sounded best to me, regardless of footer type where placed on baseplate. As said before,  I have come to the conclusion the baseplate is tuned with the stock footers as being integral to the sonic signature 

[Evo1668]

3 hours ago, PYP said:

@Evo1668, does your ER feed the MU1?  And have you tried the MU1 without it?

Yes the ER feeds the MU1 from the ‘A’ side.  No I have not tried MU1 into a standard switch. 

[Evo1668]

Yes I have copied my whole library onto SSD in the MU1.  I have multiple albums/tracks I can compare between SSD, NAS and streamed from Tidal. The Difference is not subtle - the SSD version just sounds really focussed and correct- I think a previous poster said your gear just gets out of the way - I would agree with that.  In comparison the NAS sounds really good, but slightly out of focus while the streamed version again is good, but sounds slightly muffled if compared to the other two 

[Evo1668]

I will preface this post and say I am a lifetime Roon user - for sound quality comparisons previously when I used my Linn Klimax DS3 I always found a direct approach using Linn’s own app and DLNA - the sound quality always edged out using Roon direct through the KDS. Although the Roon user interface, library management, artwork, bio’s, app use etc, made Roon my preferred choice of software player.  The SQ differences by the way was not massive but the DLNA feed always had so narrow a SQ lead over Roon.  Although during the six or so years I’ve used Roon, this margin has narrowed with subsequent software releases.  The remarkable thing that struck me when I first listened to the MU1 was as if any SQ issue had been completely removed from the Roon/MU1 equation - 

 

Replacing my beloved KDS (I had been a Linn DS owner for over 12 years) with the MU1 became a no brainer - I think you would be extremely hard pressed to identify any Roon SQ limitation with the MU1

[Evo1668]

31 minutes ago, FredM said:

Back in business, an internal SSD is installed 👍. The NAS won’t be replaced, it was primarily used for music files anyway, so another device bites the dust.

 

Moving music to the SSD was easier then expected. Now I only need to figure out how to make a Roon backup on the pc.

Which SSD did you install?   Did you install this yourself or did your dealer do it for you.  I was thinking of upgrading my SSD 

[Evo1668]

On 3/1/2022 at 8:51 PM, AnAndGate said:

I had a question for those with a MM Tambaqui and Grimm MU1, which unit do you use to control volume. Is one supposed to be superior to the other? thanks

I don’t have a Tambaqui DAC, but your question spurred me on to finally check against my D&D speakers, which has the DAC in the speaker.  The DAC (8C) controlling volume sounds to my ears superior (even more goosebumps) versus controlling the volume in the MU1 itself.  Unfortunately I do lose the convenience of controlling the volume through Roon using MU1 is a downside for me - although the D&D uses an app called Ascend which I can control volume fairly easily using my phone. Controlling volume with other Dacs of course may vary…..

[Evo1668]

3 hours ago, PYP said:

Are they?  

 

Is it correct that if you check the "DIGx" output box on the MU1, then Roon's volume slider is using the MU1's variable FPGA volume control (and that unchecked = fixed, that is full volume = passthrough to DAC/preamp, etc.)?  

yes as I understood things that is supposed to be the case - although in the options I have outlined below, to my ears they all sound different in the order least to most transparent 
 

I believe the variations are :- (excluding Roon DSP vol) 

Roon         ——>       MU1    ——> DAC/pre

 

Device*   ——->      digi   ———> fixed/0db

fixed.        ———>     digi* ———> fixed/0db

fixed         ———>     off.  ———> variable* 

 

* = where volume is controlled

[Evo1668]

5 hours ago, skatbelt said:

 

I think they are quite close. Initially the Kii three's impress more due to a somewhat sharper placement of elements in the sound stage. But after longer listening, they are also a bit more edgy and fatiguing. The Dutch & Dutch 8C's in comparison are a bit more relaxed (musical?) and have a deeper low end. Differences are fairly marginal.

 

I miss the real connection with the music in both. As I indicated in a previous post, I suspect that this is due to the built-in DAC's (jitter reduction, reconstruction filters, etc.) and to a lesser extent to the source. May be also the side effects of the intensive DSP. I have not heard them in combination with the MU1 but I can well imagine that this will be a big improvement compared to lesser digital sources.

I’ve been an 8C user for 3 years now and with the MU1 it is a sublime listening experience. I’ve recently discovered volume control is best at end of chain closest to speaker ie 8C; even greater level of transparency. Will have to compare back on the MU1 see if the upgrade has improved the digital volume 

[Evo1668]

Dutch & Dutch 8c and 2FS sampling.  A SMSL Sanskrit Mkll and 4FS for headphone listening 

[Evo1668]

Eelco  replied to one of the first UK reviews of the MU1 by The Ear two years ago in it he states

 

https://the-ear.net/review-hardware/grimm-audio-mu1-digital-hub-network-streamer-server/

 

“it is interesting to read that Jason prefers to disable the MU1 upsampling, and also the internal fpga upsampling of the iFi DAC (“bit perfect’ mode). The iFi DAC has a custom ‘interleaved’ construction of 4 Burr-Brown DAC chips. It makes me wonder if this DAC topology for some reason performs better when fed with a lower sample rate. It is hard to tell. In any case just like iFi we offered the option to turn the fpga upsampling off to check which setting offers the best sound quality. Usually upsampling wins, but you never know. For example, with some pop albums, the ‘edge’ that lower quality upsamplers in DAC chips offer was part of the decision making during mastering and could be missed by some.”

Eelco Grimm, Grimm Audio

[Evo1668]

I think I must be an outlier of MU1 owners not using the usual aes cables mentioned on here - one cable I have been bowled over with which I do use with the MU1 is the lesser known Anticables from Paul Speltz - sounds extremely musical to me and Paul offers a complete money back guarantee 

[Evo1668]

23 hours ago, FredM said:

A while ago Hans Beekhuyzen reviewed the Townshend pods/platform with his MU1: https://www.youtube.com/watch?v=cpzOkoeDOkc&list=PLMbsmejHnP8EK7U6mfXbimY6AGvU9yCc-&index=4

 

It seems a review of the new Stack Audio equipment isolators is pending: https://www.youtube.com/watch?v=l-q_zpw4l1M&list=PLMbsmejHnP8Hu8ALOlQPSgtKmpF6fnI5P 

 

 

 

I can attest to using the Townshend pods beneath the MU1 - currently experimenting using these along with the metal disc part from the smallest HRS footers which the MU1 feet make contact with - have tried footers/pods at various points beneath MU1, but always prefer isolation contact directly with MU1 feet/blocks which  have their own form of isolation built in. 

[Evo1668]

19 hours ago, stevebythebay said:

What rack is your equipment resting on?

The rack is a FE Signature Pagoda 

[Evo1668]

On 11/15/2023 at 12:26 AM, PYP said:

 

Having a similar experience with these footers.  After settling in it is clear they are staying.  Agree also about the Muon Pro.  I don't hear any downsides.  

Comparing the Auva footers against the Townshend Seismic footers. I have already removed the stock feet and have been using both footers located in same location as the stock feet.  I didn’t think you could beat the Townshend footers, but the Auva just does that extra something for the music, even though the Townshend appear to reveal a smidgen more highlighted detail.  Best way I could summarise and describe the differences is like the filter effects you apply to iPhone photos - the stock feet the original photo - Townshend is vivid -and Auva is dramatic, so damn engaging.

[Evo1668]

35 minutes ago, PYP said:

Good and helpful distinction.  Just curious:  are you using three or four Auva under the MU1?  I started with four and, after reading the review at https://highfidelity.pl/@main-1332&lang=en , am now trying three to hear any differences.  

 

I also tried four under my power conditioner and while the effect was much less than the MU1, they did further refine the highest of the HF.  That surprised me since the Shunyata only has passive components.  It would make more sense to me if the conditioner used a large transformer.   Those do vibrate.  

 

 

I’m using 4 feet. I have tried 3 footers in past, but given most of the MU1 mass is towards rear left it just feels unbalanced using 3.  I did try the Auva briefly earlier with 3 and there’s a tiny bit less detail, although prat seems more apparent,  but you seem to lose a bit of that magic that invites you into the music.  But there again that’s probably more than likely my own expectation bias at play or I’m imagining differences

[Evo1668]

49 minutes ago, TheAttorney said:

How did you remove the stock footers? Did you have to take MU1's top plate off to unscrew them from the inside?

I remember your post earlier this year about being very impressed by the Townsend Seismic pods, but didn't you place them directly under the stock footers? What made you change?

 

I was tempted to try the pods, but I didn't like their very obvious appearance, nor their price at £120 per footer, which was more than I was prepared to spend. So I'm pleased the Auva's compared so well to the pods.

You have to open up the case to remove the stock footers. Just make sure you use an exact Phillips screwdriver head as it is easy to damage the existing countersunk bolts. Bear in mind the front right inner bolt is an upright that is attached to the footer and clamps a cable coming from one of the SSD drives. Not sure if this affects the integrity of the cable as an attachment point, although it is a stiff cable and doesn’t move at all - I had no way of refitting the post sans removal of this footer leaving the cable unclamped. 
 

I used the pods as I was already using the seismic podiums as platforms under my 8C Speakers and they do reveal a wealth of hidden wonders from your existing speakers - but they are quite pricey as speaker platforms but as I said reveal what your speakers are capable of actually achieving 

[Evo1668]

On 11/17/2023 at 10:52 AM, TheAttorney said:

How did you remove the stock footers? Did you have to take MU1's top plate off to unscrew them from the inside?

I remember your post earlier this year about being very impressed by the Townsend Seismic pods, but didn't you place them directly under the stock footers? What made you change?

 

I was tempted to try the pods, but I didn't like their very obvious appearance, nor their price at £120 per footer, which was more than I was prepared to spend. So I'm pleased the Auva's compared so well to the pods.

What made me change and remove the stock MU1 footers?  I just felt the contact area of the seismic footers when positioned at the four corners, were being compromised by the stock foot and needed a more uniform surface contact area - this was confirmed when listening with the Auva as well - trying both designs with and without the stock feet in place.  I also don’t care for Hans’ positioning over the baseplate and case edges, as it ever so slightly hardens the presentation and  compromises interferes with the soundstage to my ears.

 

I said previously that both Seismic and Auva compared favourably with each other - one vivid the other dramatic.  Trying to decide which footer I preferred - listening with each design in place over a couple of days, I kept missing what the other footer design contributed.  In a moment of curiosity, I thought to try both footer types together.  The long and short of it being,  the Auva EQ are best placed under the seismic pods - a bit Frankenfooter maybe? 😂 - but both footers together produce something quite remarkable. - it’s not subtle.  You hear in disbelief such tiny details, clearer vocal articulation, mix techniques (good and bad), increased low register articulation and bloom, an increase in soundstage depth and width.  

I reached out to Stack Audio giving my feedback on the Auva and also my experience combining them with the Seismic pods.  They offered to have a listen to the combination as they have the pods themselves  - feedback was largely in agreement with what I was disbelieving/hearing. In that music is overly immersive with a soundstage not heard before.  A wonderful improvement.

 

 

[Evo1668]

3 hours ago, Ronnie112 said:

Of course all depends on the circumstances and your power grid. In mine I have a nasty DC offset, which unfortunately makes transformers hum from time to time. Both in amps as in isolation transformers, so that doesn't do the trick for me. With the filters used so far I found some change for the MU1 and MU2, but not necessarily an improvement.

 

@PYP tried it yesterday without the Flux50 and into the Puritan 156 filter. Next to some additional blackness and ambient details I could hear the sonic fingerprint of the filter through the MU2. Which is not necessarily a good thing, since I find the filter to add some glare/edginess and artificiality which I don't really like so far. Maybe it needs to settle in or another power cable between wall outlet and filter, I don't know. So for now I'll keep the MU2 on its own dedicated power circuit (with nice fuses) with a Flux-50 killing some noise and EMI in the last inches.

 

Didn't try filters like Shunyata Denali or (the latest buzz here in NL) Sygnus. They will definitely yield good results, if it was not my DC offset upsetting things. 

 

Agree fully with the ethernet remark. Heard clear differences upgrading ethernet cables and switches, which is a good thing as you can further improve on an already excellent product.

Did you try the Ultimate cable with the 156.  There’s quite a few very positive reports using the Puritan Ultimate cable between the wall socket and the 156 and further improvements after a settling in period - sterile/artificial sounding being a common initial first observation by many.  

[Evo1668]

On 12/18/2023 at 11:46 PM, FredM said:

Welcome 👍

 

 

Based on the available first hand experiences the MU2 pre-amp is not a byproduct. So far it seems to perform at least around the €6K - 10K price range for the pre amp only (also see comments in the video reviews from Hans Beekhuyzen and Alpha Audio). 

 

 

I’m afraid I can’t help you here, I have very limited DSD content. I just press play 🙂

 

 

Nope. SQ wise it doesn’t matter if you use the internal MUx Roon core or an external Roon core. An external Roon core is convenient for very/extremely large music collections (smoother navigation).

 

 

Fully agree, besides the SQ I also very much value an intuitive user experience for navigation and to discover new music. Roon is my favorite. At home Roon also controls other streaming speakers (kids & living room), very simple and convenient for everyone.

 

 

Thanks, after trying out 5 different conditioners/filters (with prices over €5000) on my Grimm set, I prefer the pure Grimm set, which closed the conditioner chapter for me (ps. I just searched for the Shunyata Everest and Omega cable, I’m not tempted 🙂)

 

 

Thanks for sharing 👍 

On the conditioner mains front for the MU1 has anyone else tried the LessLoss 640x firewalls into the Grimm?   I tried one a few nights ago into the back of the Grimm - a spare which I forgot I still had in storage following our big move last year.  It sounded damn good, takes it to foot tapping amazing. I’ve been running the 640x for a while into the back of my 8C speakers and I read somewhere that running these firewalls in series to your main source,  improves things even further by some margin.  So I removed the two from the speakers and connect the speakers directly into the PS Audio PPP.  Now i currently have three of them in series on the MU1 -  foot tappingly stunning - the music surrounds you and just sucks you in.  I’m leaving things like this for the next few weeks and then I’ll remove them and see if the magic is still there, or if there is something else going on 

[Evo1668]

I know it doesn’t make sense - I never got my head around the technology, they do go into lots of detail on their website about it and I think the manufacturing process is quite intense for these devices. You can build one yourself (they do a diy version of the firewall - if you’re ok with wielding a soldering iron) which makes price of entry a lot less wallet stretching - in fact the one I tried first into the Grimm was one I built myself - try the stock Grimm cable instead and save on the Shunyata