Grimm MU-1 server review - A new force in digital source?

[fast.freight]

As tutored by Bill Parish, 'the 6v output sounds better'. It does to me. Some recordings are a bit 'hot' and distort or clip. With my Audionet preamps, I can hear the clipping grow over the 8 steps per (something) and then decrease. Once again Bill told me a solution. Using the Mola Mola app, go to 'Edit Preset" (of the input with the Tambaqui) . Scroll to 'Volume Offset" and set it to -2. Sounds better than 2v and does not clip. This is different than decreasing the digital volume on the Tambaqui; don't do that, keep it on direct if you have a preamp.

 

[PYP]

MU1 is incredibly stable. Still loving this combo. I tried experimenting with different power cables to the MU1 and it’s quite difficult for me to search for any changes.

Also on the subject of the Tambaqui, I started using it on the default 6V output and to my amp. I was dutifully thinking 2V output over single ended was the de facto standard. Hell to the nah…! Tying back the MU1 I also ticked the 3db headroom option and man the combo is just exquisite

Thanks for mentioning the headroom option. Experimenting with it now. Did you pick that option because of problems with pop albums or to use a higher volume setting on the Tambaqui (or just tried it and liked it)?

I'm going straight to my amps too and the 6v works for me.

 

[Low325]

Thanks for mentioning the headroom option. Experimenting with it now. Did you pick that option because of problems with pop albums or to use a higher volume setting on the Tambaqui (or just tried it and liked it)?

I'm going straight to my amps too and the 6v works for me.

Yah, really I just saw Hans mention it on his YT channel, and I normally would use a some dsp where needed, for example in a previous set up, without the MU1 and MM, I would use a -12db filter or some sort where available in my DACs or streamers. Another example in my previous Lumin X1, I set the output to low, whereas setting it too high, I felt the signal came in too hot direct to my amplifier. Again, so many variables have changed since settling with the current system…that I appreciate so much the central flexibility and the simplicity of the MU1 to let it handle all the processing and send the signal (let it be a non-bit perfect one) to the MM. The music sounds more natural to my ears, while still having plenty of dynamics and punch.

It’s just not pop music where i find the extra setting handy…even listening to jazz or orchestral, I think it just gives a more natural presentation in my room and to my ears. (Even with 2v setting in the MM.)This is probably where one would argue the benefit of a preamp so one could level match the gains… fwiw, I think 6v in the MM is labeled for balanced xlr but I am going single ended...so we are not getting the full default voltage as it passes through, with all this considered and throwing out fictitious numbers here, I think it is reduced to about 4v going into my amp (I should measure it with my volt meter one day - keep in mind, I have a gain control power amp). To my ear, everything has more body, more natural, and scales in the dynamics of any music that passes through, to my ears anyway.

 

[PYP]

fwiw, I think the 6v setting in the MM is for balanced, but I am going single ended...

Thanks. I'm using XLR from Tambaqui to Kalugas. Having the flexibility of different settings is great since it provides some fine tuning for individual preferences and cable choices, as you mentioned. I will try the MU1 headroom feature for a few days and then try without. That usually tells me what I need to know.

 

[Low325]

It’ll be YMMV type of thing….. shouldn’t take long at all to see if you like it….good luck!

 

[fast.freight]

Hello @Gjo, I will jump in here, responding to an older post of yours, as I have similar equipment. I have two systems, one with stand alone Tambaqui, and the other with Makua and onboard Tambaqui. The stand alone is my reference system, but both are good. I formerly had an Aries G2.1 with custom Sean Jacobs Power supply in the reference system. I replaced this Auralic Aries G2.1 with the Grimm Mu1. The modded Aries was good. The Grimm is better, and MUCH more stable. Music flows more easily and smoothly. More lifelike and engaging. I can easily switch the systems, by moving the Grimm. When I do this, they system with the Grimm gets better, the other goes backwards. Easy to hear. I have also compared the USB inputs to the AES inputs. And, it depends on the cable used. A good USB beats a cheap AES. My reference AES is K-S Elation, and it surpasses the K-S Realization USB cable. NO silver for me in either of my systems. I have also demo'd Network Acoustics Muon AES. It is a close second to the K-S AES cable.
I also use Roon and the Grimm again runs Core without issues. So I eliminated a Nucleus + along the way.

 

[PYP]

Hello @Gjo, I will jump in here, responding to an older post of yours, as I have similar equipment. I have two systems, one with stand alone Tambaqui, and the other with Makua and onboard Tambaqui. The stand alone is my reference system, but both are good. I formerly had an Aries G2.1 with custom Sean Jacobs Power supply in the reference system. I replaced this Auralic Aries G2.1 with the Grimm Mu1. The modded Aries was good. The Grimm is better, and MUCH more stable. Music flows more easily and smoothly. More lifelike and engaging. I can easily switch the systems, by moving the Grimm. When I do this, they system with the Grimm gets better, the other goes backwards. Easy to hear. I have also compared the USB inputs to the AES inputs. And, it depends on the cable used. A good USB beats a cheap AES. My reference AES is K-S Elation, and it surpasses the K-S Realization USB cable. NO silver for me in either of my systems. I have also demo'd Network Acoustics Muon AES. It is a close second to the K-S AES cable.
I also use Roon and the Grimm again runs Core without issues. So I eliminated a Nucleus + along the way.

Have you tried your setup with and without the Muon Pro filter since getting the Grimm?

Also curious if you had the standard Verizon modem prior to the Fios modem and if that made a difference. Can a linear power supply be added to the Fios?

Since the MU1 seems to eliminate most of the upstream hash, I'm wondering if there is room for improvement upstream.

 

[fast.freight]

Hello @PYP, Good questions:

Have you tried your setup with and without the Muon Pro filter since getting the Grimm?

Yes. I had the Muon's (one in each system) prior to getting the Grimm. When using the onboard streamers in the Tambaqui's, the Muon made a bigger difference. but, I did out it in and out quite a bit after I had the Grimm. The Muon still improves things, just not as much. I also have the M12 Gold switch, and some say I should not need the Muon with it. Perhaps if the switch was JUST IN FRONT of the Grimm, but my M12 switch is where I need a switch, upstairs in my office. so I have 30 feet of Supra Cat 8 between the upstairs switch and my music room and my Muon > Grimm. I love the passive nature of the Muon, so no extra power supply cluttering my audio rack. The Muon sits invisably in the rear of my rack, cool and smooth!

Also curious if you had the standard Verizon modem prior to the Fios modem and if that made a difference. Can a linear power supply be added to the Fios?

I have always had FIOS but recently upgraded to 1G internet service and that came with a new modem / router. so there is fiber to my garage and then a long filthy run of cat 6 to my new FIOS / Verizon Gateway G3100 modem / router. My wifi is disabled on the G3100 and a direct ethernet connections go to my Eero mesh 6pro wifi routers. Another high end cable goes to my M12 switch which only feed my two audio systems.
Interesting timing to ask about power supply for this G3100. I am now using my Sean Jacobs AR6 to power my switch and I want to power this G3100. It has some kind of unique DC input with a standard 5.1mm barrel but a larger center pin that does not go into the standard DC fittings. Joe Kubala is personally helping me source this if possible, because I have the output ready and available on the Sean Jacobs. You can find other comments around on this PIA DC fitting on the G3100. There is another 1G Fios modem but I do not have that. I did succeed in getting Verizon to send me another wall wart power supply (mine was faulty to send to K-S to study, so we shall see! So I am all about adding a good linear power supply to the Modem and separating the wifi completely.

Since the MU1 seems to eliminate most of the upstream hash, I'm wondering if there is room for improvement upstream

Yes Yes Yes I think everything matters. Even you just said 'removes most of the upstream hash' My M12 Gold switch is upstream and makes a big difference. The power supply on the switch makes a big difference. I am now playing with the fuse in the Sean Jacobs power supply, burning in a SR Master fuse. It is much more dynamic and detailed than the stock fuse and this is just for the switch! So far the SR Master is a bit bright but I am told to be patient and let it settle in. Chris at VH Audio says at least 150 hours. And then still the Muon helps.

Now you should ask how do the Audionet amps compare to the Kalugas. I have been there! Take care, Ken

 

[PYP]

Now you should ask how do the Audionet amps compare to the Kalugas. I have been there! Take care, Ken

I cannot afford to ask that question.

Great information. Thank you. Good luck on getting the right power connector for the router.

 

[PYP]

It’ll be YMMV type of thing….. shouldn’t take long at all to see if you like it….good luck!

I always assume mileage will always vary. So many variables, most importantly our own ears/preferences.

Yesterday, I switched off the 3db headroom function and confirmed I prefer that setting (that is, not using the headroom option). Listening to Elina Duni's A Time to Remember confirmed the preference. What a beautiful voice and album (Qobuz 88/24, highly recommended).

The difference wasn't large to my ears. Not to the ears of my wife either. I hadn't told her about the switch (before or after) and she didn't comment on the sound. She is a music lover with keen ears who will let me know if something doesn't sound right. I also observe how she uses the system. After the MU1 was in our system for a while (I would say "broken in") she started to listen more often and with greater enjoyment (including, greater volume ).

 

[fast.freight]

I am today receiving demo JCAT S1 streamer. I will be able to compare it directly to my grimm Mu1. As I use AES on the Grimm, and the S1 is USB, it should be only a network wire change to A/B. Of course the S1 has its own (JPLAY) software and app, and the Grimm runs Roon, I believe this new S1 also has the witch capability to compare with my M12. The S1 can be switch or steamer, not both at once. Marcin says having one as switch in front of the other as streamer is amazing.

 

[matthias]

I am today receiving demo JCAT S1 streamer. I will be able to compare it directly to my grimm Mu1.

I am very curious about your impressions

Matt

 

[PYP]

I am today receiving demo JCAT S1 streamer. I will be able to compare it directly to my grimm Mu1. As I use AES on the Grimm, and the S1 is USB, it should be only a network wire change to A/B. Of course the S1 has its own (JPLAY) software and app, and the Grimm runs Roon, I believe this new S1 also has the witch capability to compare with my M12. The S1 can be switch or steamer, not both at once. Marcin says having one as switch in front of the other as streamer is amazing.

It is interesting how many designers are moving their attention upstream to the switch (makes sense). Recently watched Bill's (GTT Audio) video about his new offering, which he uses with the MU1. That one has a "clean" and "dirty" side.

 

[Rumpole]

Did Grimm slip a bribe to someone at NASA? Now I have to get one!

 

[PYP]

Did Grimm slip a bribe to someone at NASA? Now I have to get one!

View attachment 117142

remember to request the one that can withstand 5,000 degrees F.

 

[fast.freight]

Hello, please if interested see my comparison of the Grimm MU1 vs the XACT S1 streamer on the S1 forum.

 

[Jedclampet]

Hello @PYP, Good questions:

Yes. I had the Muon's (one in each system) prior to getting the Grimm. When using the onboard streamers in the Tambaqui's, the Muon made a bigger difference. but, I did out it in and out quite a bit after I had the Grimm. The Muon still improves things, just not as much. I also have the M12 Gold switch, and some say I should not need the Muon with it. Perhaps if the switch was JUST IN FRONT of the Grimm, but my M12 switch is where I need a switch, upstairs in my office. so I have 30 feet of Supra Cat 8 between the upstairs switch and my music room and my Muon > Grimm. I love the passive nature of the Muon, so no extra power supply cluttering my audio rack. The Muon sits invisably in the rear of my rack, cool and smooth!


I have always had FIOS but recently upgraded to 1G internet service and that came with a new modem / router. so there is fiber to my garage and then a long filthy run of cat 6 to my new FIOS / Verizon Gateway G3100 modem / router. My wifi is disabled on the G3100 and a direct ethernet connections go to my Eero mesh 6pro wifi routers. Another high end cable goes to my M12 switch which only feed my two audio systems.
Interesting timing to ask about power supply for this G3100. I am now using my Sean Jacobs AR6 to power my switch and I want to power this G3100. It has some kind of unique DC input with a standard 5.1mm barrel but a larger center pin that does not go into the standard DC fittings. Joe Kubala is personally helping me source this if possible, because I have the output ready and available on the Sean Jacobs. You can find other comments around on this PIA DC fitting on the G3100. There is another 1G Fios modem but I do not have that. I did succeed in getting Verizon to send me another wall wart power supply (mine was faulty to send to K-S to study, so we shall see! So I am all about adding a good linear power supply to the Modem and separating the wifi completely.


Yes Yes Yes I think everything matters. Even you just said 'removes most of the upstream hash' My M12 Gold switch is upstream and makes a big difference. The power supply on the switch makes a big difference. I am now playing with the fuse in the Sean Jacobs power supply, burning in a SR Master fuse. It is much more dynamic and detailed than the stock fuse and this is just for the switch! So far the SR Master is a bit bright but I am told to be patient and let it settle in. Chris at VH Audio says at least 150 hours. And then still the Muon helps.

Now you should ask how do the Audionet amps compare to the Kalugas. I have been there! Take care, Ken

Has Bill shown you the Dejitter gear connect x. It addresses exactly your thoughts here.

 

[Jedclampet]

It is interesting how many designers are moving their attention upstream to the switch (makes sense). Recently watched Bill's (GTT Audio) video about his new offering, which he uses with the MU1. That one has a "clean" and "dirty" side.

I own the units your referring to from Bill, relatively low cost of entry and I find the improvements kin to an upgrade of better cables for example. I also have his Apple TV x I use for YouTube videos which in n of itself is amazing with the clean wifi it too is on another level.

 

[PYP]

I own the units your referring to from Bill, relatively low cost of entry and I find the improvements kin to an upgrade of better cables for example. I also have his Apple TV x I use for YouTube videos which in n of itself is amazing with the clean wifi it too is on another level.

I read about the switch but wonder if it would help my setup and whether it is the right solution. The only wired connection is between the router and the MU1. Everything else is connected to the router via wifi. I also prefer passive solutions, if possible. Summers here often result in power outages and the turn-on sequence is a turn off. Better to just have the power automatically power up the router and MU1 without further complications.

I wonder if Bill will have a MU2 on tour. That is how I listened to a Tambaqui (this was before any professional reviews, which weren't needed ).

 

[fast.freight]

I read about the switch but wonder if it would help my setup and whether it is the right solution. The only wired connection is between the router and the MU1. Everything else is connected to the router via wifi. I also prefer passive solutions, if possible. Summers here often result in power outages and the turn-on sequence is a turn off. Better to just have the power automatically power up the router and MU1 without further complications.

Hello, I had also separated my wired music form my whole house wifi. thus the music was separate and 'clean' of all the house traffic. This includes phones, TV's, security, printers, computers, Alexis, Siri etc. But not so. Even if the wired music is separate from all the wifi or other wired stuff to the router, it is all still on the same network. So all the chatter form all the devices invade the music as well. You can add a quality switch between your router and the MU1, and that helps a lot. Like the NA Tempus or the JCAT M12. But Bill's Switch X goes beyond just a switch cleaning up the signal. It completely creates a new music network 'clean network' which is completely separate of all the other home noise. Taiko does this for well over twice the price of GTT's Switch X and Wifi X.