Grimm Audio MU1 and MU2 Music Players

[Mike123]

In a situation where I could substantially reduce box count by selling my preamp, DAVE and MU1 and buy the MU2. My only reservation is if there is a PT feature on MU2 for home theatre use case.

[stevebythebay]

28 minutes ago, Ronnie112 said:

I have that integrated amp with a bypass switch and can attest  the pre amp function of the MU2 is clearly outperforming. The MU2 on full throttle bypassed its attenuator (as far a I know) and I've compared bypassing the MU2, combining both attenuators and bypassing the SPEC pre amp, which was clearly offering the best performance. With the MU1 it was the opposite and preferred the pre amp of the SPEC (over the MU1&Sonnet Pasithea). Just my opinion, but hope it answers your questions. 

Huh?  The XP-12 is not an integrated amp but a preamp.  I'm unaware of any current Pass Labs integrated amp offering pass-through capability, which as I recall, allows for unity gain type support - bypassing the preamp's function and sending unconstrained to separate amps stereo inputs.  Sorry, but I'm really confused as to what you compared and exactly how.

[Ronnie112]

Was responding to your own remark:

"And an even more "interesting" situation presents itself when faced with using the MU2 with an integrated amp, unless the integrated offers the ability to cleanly "defeat" or "bypass" its preamp function. "

My SPEC RSA-M99 has that function".

[stevebythebay]

58 minutes ago, Ronnie112 said:

Was responding to your own remark:

"And an even more "interesting" situation presents itself when faced with using the MU2 with an integrated amp, unless the integrated offers the ability to cleanly "defeat" or "bypass" its preamp function. "

My SPEC RSA-M99 has that function".

Your original response was  "I have that integrated amp with a bypass switch and can attest  the pre amp function of the MU2 is clearly outperforming."  The one they were comparing was the Pass Labs “preamp” not your SPEC integrated.  Now I understand where you're coming from.  What’s still puzzling is what the reviewers were doing to make their comparison. 

[Ronnie112]

2 minutes ago, stevebythebay said:

 Now I understand where you're coming from. 

Yes, can comment on my own experiences only, using my SPEC not the Pass Lab. Was trying to share my findings playing around with the volume setting options that provided. Sorry if that was confusing.

 

But on your remark, indeed if you have an integrated amp without bypass function, one needs set the MU2 to maximum volume and use the volume controll of the integrated amp. Which is not using the MU2 at best ability, as the pre amp integration is one of its benefit by design. Having both attenuators in play gave the worst results (again with me) so you have to choose holding on to the integrated amp or sell it off and buy yourself a power amp. 

[stevebythebay]

4 minutes ago, Ronnie112 said:

Yes, can comment on my own experiences only, using my SPEC not the Pass Lab. Was trying to share my findings playing around with the volume setting options that provided. Sorry if that was confusing.

 

But on your remark, indeed if you have an integrated amp without bypass function, one needs set the MU2 to maximum volume and use the volume controll of the integrated amp. Which is not using the MU2 at best ability, as the pre amp integration is one of its benefit by design. Having both attenuators in play gave the worst results (again with me) so you have to choose holding on to the integrated amp or sell it off and buy yourself a power amp. 

Thanks for the clarification.  You've certainly helped position the MU2 for those of us with preamps we love and need (at least in my case my Spectral preamp is "joined at the hip" with my Spectral mono blocks in terms of performance).  Spectral is somewhat unique in designing a sort of Apple-like ecosystem of products, even extending their synergy to Spectral "driven" MIT interconnects, speaker cables, and even power cables.  It's a bit of lock-in but ensures issues don't arise from mismatching components.

[Ronnie112]

Had the same thing when trying out Goldmund amps. They also sounded best with Goldmund pre amps. In your case it is the question if a MU2 betters your MU1/DCS Vivaldi upsampler and Apex DAC & Clock. Or just be a happy camper as you are now. 

[PYP]

20 minutes ago, Ronnie112 said:

 

But on your remark, indeed if you have an integrated amp without bypass function, one needs set the MU2 to maximum volume and use the volume controll of the integrated amp. 

The manual says:  "In case you prefer to use the volume control of a connected pre amplifier, it is suggested to set the startup volume to 0dB and not touch the main dial or Roon slider. This effectively bypasses the MU2 volume control."  

 

So, the full output level of the DAC is sent directly to the MU2's outputs?  That would yield the sound of the streamer/DAC without the preamp.  Yes?  

[stevebythebay]

3 minutes ago, Ronnie112 said:

Had the same thing when trying out Goldmund amps. They also sounded best with Goldmund pre amps. In your case it is the question if a MU2 betters your MU1/DCS Vivaldi upsampler and Apex DAC & Clock. Or just be a happy camper as you are now. 

Already determined that one when I first did my testing of a loaner.  The upsampling done via the dCS Upsampler is noticeably better than the MU1, which I figured would happen, due to the synergy with the dCS Vivaldi APEX DAC (particularly with the various ways the filtering in each component works with one another).  Again, a case where the manufacturer completes the puzzle for you in the best way possible (and with a separate master clock for the stack, to boot).  Of course, you can never be sure until you try it out.  If the MU2 option would prove to be better, it would certainly be a surprise, and put loads of money back into my pocket and lots of recovered rack space.

[PYP]

2 minutes ago, stevebythebay said:

If the MU2 option would prove to be better, it would certainly be a surprise, and put loads of money back into my pocket and lots of recovered rack space.

do you intend to demo the MU2?  that would be a fascinating (vicarious) comparison.  🙂

[stevebythebay]

2 minutes ago, PYP said:

do you intend to demo the MU2?  that would be a fascinating (vicarious) comparison.  🙂

If my dealer gets one in for a demo, I might ask to get on a list.  However, since he's got all of the same components in house that I'm using, (amp, preamp, dCS stack, and speakers) I'll leave it for the dealer to test if they've got the inclination.  

[Ronnie112]

"so, the full output level of the DAC is sent directly to the MU2's outputs?  That would yield the sound of the streamer/DAC without the preamp.  Yes?"

 

Yes, thought that is the case. And rumor has it that an update is in the works of proving pass through options for the MU2 with adjusted output voltage to match to external pre amps.

[PYP]

1 minute ago, Ronnie112 said:

"so, the full output level of the DAC is sent directly to the MU2's outputs?  That would yield the sound of the streamer/DAC without the preamp.  Yes?"

 

Yes, thought that is the case. And rumor has it that an update is in the works of proving pass through options for the MU2 with adjusted output voltage to match to external pre amps.

That would be a nice feature.  I assume there will be many people who want to keep their preamps and have as ideal a match with the MU2 as possible.  

 

Not my case since I do not have a preamp in the chain (using the digital attenuator of the Tambaqui). 

[Terrycwk]

On 12/14/2023 at 10:38 AM, Ronnie112 said:

Thanks for sharing. Funny, I came from the same DAC (Sonnet Pasithea) as them and can fully agree with their findings. MU2 is extremely transparant and at the same time completely natural sounding. I also noticed it makes my speakers go lower than they should be able to do. I forget to skip to next songs and listen complete albums. Just like them, can't stop listening.

 

And (what they didn't say) it images like crazy. Not just in front of the speakers. Last week I had my head  behind my speaker to pick something up, and the full ambiance was still there. It shouldn't be, but still there. It is so natural that it is like live music. My youngest sweared he heard someone singing in the living room the other day. He was on the 1st floor in his room. It is unreal realistic. 

 

By the way, had all the intentions of buying my set of Auva feeters. Came home with a 'wonderplank' instead (picture) and think I will not part from it anymore.

@Ronnie112 Just curious if you find the MU2 to be not so power cord sensitive like the MU1?  Thanks!

[Ronnie112]

6 hours ago, Terrycwk said:

@Ronnie112 Just curious if you find the MU2 to be not so power cord sensitive like the MU1?  Thanks!

Merry X-mas everyone! Enjoy the time with your loved ones.

 

On your Q, first of all, I found the MU1 sensitive to power cords. Tried 6 or 7 different cords/plugs with performance of the MU1 between somewhat uninspiring to jawdropping. What is different is that it was not necessarily like the more expensive, bulkier or exorbitant the better it was. Found one of my spare Kimber cables and the PowerFlux I have in use now, providing the best results for my setup/taste.

 

As I still have 3 out of the 7 cables that I tried on the MU1, I tried them on the MU2 as well, with pretty much the same outcomes. The MU2 has a bit higher power consumption (1A fuse) and gets warmer (needing more rack breathing room). But with regard to power cables and other peripherals the MU1 and MU2 are pretty much alike.

[Mike123]

7 hours ago, Ronnie112 said:

Merry X-mas everyone! Enjoy the time with your loved ones.

 

On your Q, first of all, I found the MU1 sensitive to power cords. Tried 6 or 7 different cords/plugs with performance of the MU1 between somewhat uninspiring to jawdropping. What is different is that it was not necessarily like the more expensive, bulkier or exorbitant the better it was. Found one of my spare Kimber cables and the PowerFlux I have in use now, providing the best results for my setup/taste.

 

As I still have 3 out of the 7 cables that I tried on the MU1, I tried them on the MU2 as well, with pretty much the same outcomes. The MU2 has a bit higher power consumption (1A fuse) and gets warmer (needing more rack breathing room). But with regard to power cables and other peripherals the MU1 and MU2 are pretty much alike.

Furtech manufactures the Powerflux series, correct?

[Mike123]

correction: Furutech

[PYP]

7 hours ago, Ronnie112 said:

Merry X-mas everyone! Enjoy the time with your loved ones.

 

On your Q, first of all, I found the MU1 sensitive to power cords. Tried 6 or 7 different cords/plugs with performance of the MU1 between somewhat uninspiring to jawdropping.

But have you tried the cheese tweak as shown in the Grimm Audio Mailing email?  Not sure what kind of cheese, but you need to place it off-center, apparently.  There is a marketing opportunity for Grimm if a Dutch cheese manufacturer includes that picture as a "serving suggestion."  Merry Christmas (and merry other holidays).  

[Terrycwk]

7 hours ago, Ronnie112 said:

Merry X-mas everyone! Enjoy the time with your loved ones.

 

On your Q, first of all, I found the MU1 sensitive to power cords. Tried 6 or 7 different cords/plugs with performance of the MU1 between somewhat uninspiring to jawdropping. What is different is that it was not necessarily like the more expensive, bulkier or exorbitant the better it was. Found one of my spare Kimber cables and the PowerFlux I have in use now, providing the best results for my setup/taste.

 

As I still have 3 out of the 7 cables that I tried on the MU1, I tried them on the MU2 as well, with pretty much the same outcomes. The MU2 has a bit higher power consumption (1A fuse) and gets warmer (needing more rack breathing room). But with regard to power cables and other peripherals the MU1 and MU2 are pretty much alike.

Thanks Ronnie!  Personally I find the effects of different power cords on MU1 to be minimal but since MU2 has the D/A conversion section, I would tend to think the power cord will play a larger role and your reply just proves that may well be the case.  I’m waiting to demo the MU2 now.

 

Merry Christmas everyone from the great white north!

[Ronnie112]

23 minutes ago, Mike123 said:

correction: Furutech

Yes Furutech is the brand. But don't take my findings for the absolute truth and make your own choices with your own ears.

[Ronnie112]

18 minutes ago, PYP said:

But have you tried the cheese tweak as shown in the Grimm Audio Mailing email?  Not sure what kind of cheese, but you need to place it off-center, apparently. 

Merry Christmas (and merry other holidays).  

Ha ha ha, haven't tried Gouda off centre. It was the most expensive cheese platter I've ever seen.

 

Best wishes!

[stevebythebay]

21 minutes ago, Terrycwk said:

Thanks Ronnie!  Personally I find the effects of different power cords on MU1 to be minimal but since MU2 has the D/A conversion section, I would tend to think the power cord will play a larger role and your reply just proves that may well be the case.  I’m waiting to demo the MU2 now.

 

Merry Christmas everyone from the great white north!

And I would certainly expect, with the presence of a DAC in the unit, that the MU2 will benefit greatly by having the Stack AUVA feet in support.

[Ronnie112]

Ordered my set Auva's now as well to compare against the 'wonderplank'. As mentioned in my previous post, everything that worked for the MU1 seems to work for the MU2 as well. How sustainable. 😂

[Terrycwk]

1 minute ago, Ronnie112 said:

Ordered my set Auva's now as well to compare against the 'wonderplank'. As mentioned in my previous post, everything that worked for the MU1 seems to work for the MU2 as well. How sustainable. 😂

Have been wondering what your “wonderplank” is as I really can’t tell from the photo…. 😅

[Ronnie112]

10 minutes ago, Terrycwk said:

Have been wondering what your “wonderplank” is as I really can’t tell from the photo…. 😅

It's all in Dutch, but will give you an idea: https://www.audiomaat.nl/wonderwood-underboard-copy.html