Planning to buy Grimm MU1 streamer

Good morning, I’m a happy owner of a Vivaldi DAC and Vivaldi UPSAMPLER connected to a Mutec REF10 and 2 MC3+USB and planning to buy a Grimm Audio MU1 streamer.
I was told I won’t need the MUTEC Clock and Vivaldi UPSAMPLER anymore because the MU1 must be directly connected to the DAC (how do I’ve to connect them?).
In case I’m left with a spare UPSAMPLER, may I connect it to an EAD DSP9000 pro DAC in my second system ?
I’m confused and, please be kind, let me know your expert opinion on the subject .

HI Gianni, Yes you could.

Connect the AES or SPDIF output from the Upsampler to the EAD AES/SPDIF input - it’ll have to be just a single AES/SPDIF, so the maximum upsampling PCM rate available to the EAD would be 176.4kS/s or 192kS/s, not DXD.

It should otherwise work quite well. :+1:t2:

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Hi Anup,
Thank you very much for your suggestion.
I’ll try and let you know.


Nasty question:
What can the Grimm MU1 do better than the Vivaldi Upsampler ?
(Except may be for the optional built in SSD.)

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My guess is the Grimm MU1’s Upsampling algorithm framed over AES/EBU streams imparts a different flavour to sound quality - not more accurate or any better, just different that some people subjectively prefer.

May be.
However, upsampling is limited to single AES (i.e. 192kHz), no DXD, no DSD.
But then the price is only about half that of a Vivaldi Upsampler.

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Thank you all for the much-appreciated suggestions! I’m now thinking about a different solution, but once again I need your helpful advice.
What about if I add to my system (composed of a Vivaldi DAC and Vivaldi UPSAMPLER connected to a Mutec REF10 and 2 MC3+USB) a dCS Network Bridge and, in this case, how to connect all the devices without errors to each other? Really thankful for the right answer!
best, Gianni

Why aren’t you using the upsampler for your network connection?


Why do you want to add a Network Bridge to a system that already has a Vivaldi Upsampler? The Upampler includes exactly the same functions a Network Bridge except that the greater budget available allows the Upsampler to provide a slightly better result.


Thanks Vince, thanks Pete, my incertainties dipend on my inexperience of the digital world and, in general, on the total lack of technical knowledge. My great enjoyment is listening to music and sound quality; for this I thank all those like you who help me in this regard.
best, Gianni


Let us know how using the upsampler’s bridge works for you.

Have fun!

@gianni I have had a Grimm MU1 on loan from my dealer for about 3 weeks now.

Having had it in my system for a while now I do like the MU1 a lot but I think I have decided that its dependance on using Roon is going to be the deciding factor in me not going down the MU1 route despite me having a lifetime subscription bought years ago when it was much cheaper. However for those who value what Roon does and for those who have no quibble with the Roon sound quality I think that the MU1 is a good proposition and is well worth bearing in mind and auditioning if looking for a streamer at that level.

I have been using the spdif output from the MU1 which having tried both outputs and with different cables I concluded that prefer that output compared to the MU1 AES output. Having shared my thoughts on this with the Grimm dealer and now that he has changed to the same spdif cable as me he has also decided that he also now prefers the spdif output so if you do audition the MU1 it might be worth playing with the different outputs. It could be that taking the MU1 spdif output to your Vivaldi direct rather than going through the Mutecs could pay dividends and simplify your system.

Anyway I think the MU1 is definitely worth a listen in your own system.

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Hello Nick,

I’m also considering the Grimm MU1, but I’ve not heard it yet.

Out of interest, did you play any DSD files through the MU1?

I ask because I have quite a lot of DSD albums in my library and, as I understand it, DSD files will be downsampled by the MU1 and output at a rate of 176.4 kHz.
Is that correct?

Also, which SPDIF cable did you (and your dealer) prefer?

Hi @Bauer I’m sorry I cannot help with any feedback with DSD playback as I do not have any.

The spdif cable I preferred with the MU1 was the WAVE Storm which is lucky because I manufacture them! After hearing that cable with the MU1 my dealer also swopped to using that instead of a more expensive AES cable he had been using.

If you like Roon then the MU1 is definitely worth a listen.

Hi Nick, with all respect, you seem to be a member of the trade, and as such you should publicly state that here on the community. So that we all know about you affiliation. @Phil @James

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@Ermos Sorry, knuckles duly rapped. Nick.

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No problem, thanks @NickBacon

I’lll arrange to have a listen.

Thanks Nick!

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And now there’s this:



It’s probably a great bit of kit, but it includes a DAC, which I don’t need (as I’ve got my Rossini APEX).

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