Grimm MU2 Experience

I wish my wife loved the big knob a little more often.

Kyle and Stan

Go Fund Yourself 

South Park Solicitor 

With respect to ground loop,  try a standard Cat 6 if you are using Cat7 or 8 from your switch to the Grimm.  The metal casing of the 7 and 8 plug can cause noise or hum in some set ups

@ja_kub_sz   I would encourage you to experiment with the device control vs fixed volume setting in Roon.  I have found a significant difference between the 2 settings.  I have found the fixed volume setting in Roon along with the volume fixed at +0.0Db in the MU2 to be best in my system.  The fixed volume setting in Roon offers a wider deeper and more engaging experience in my system .  Of course YMMV.  Also need to note that it seemed to take quite a period of time for the unit to break in and sound its best.  I have had it in my system for about 2.5 months I think it really just seemed to really blossom lately.  FWIW

@wlp3

As of now I’ve only run the MU2 at fixed volume through the web settings for the MU2 and haven’t (so I think) done fixed volume in Roon. Why per say is the "Roon" fixed volume better (technically speaking)? Secondly can you have the MU2 through it’s web setting be at fixed volume, and then again set the Roon-MU2 interface to "fixed" also and get the same result?

When you say "fixed 0.0db" is that the actually checked box in the MU2 we’d control setting for fixed volume? Or is that just the volume dial of the MU2 turned to that setting on the unit? Doesn’t the MU2 display screen revert to 42db in fixed volume via the web interface for the MU2? Again I sit far away from the unit, but I thought I kept seeing that on the MU2 while walking up to it.

@ja_kub_sz   In addition to the volume control on the MU2 there is a setting for Fixed Volume or Device Volume in Roon.  This is accessed by the volume control icon to the right side of the music selection window on the bottom of the screen.  Select the gear icon on the menu.  Under Audio Device window hit the Device Setup.  Under the Volume Control drop down you can select DSC Volume, Fixed Volume or Device Volume.  Device Volume will communicate volume instructions to and from the MU2.  The Fixed Volume control will send a fixed signal to the MU2.  Volume can still be controlled in the MU2.  I am using an integrated amp, so I am using the fixed volume (line out) setting on the MU2, and I have selected +0.0 db as the level of signal output to the amp, and controlling the volume with my integrated amp.  Alternatively, you could set the volume on your pre-amp or integrated to a set level and use the volume control on the MU2 to control volume.  Although the gain on the MU2 goes to +8.0 dB, Grimm advises that there may be some distortion on the higher gain settings, so +0.0 dB is the recommended maximum setting on the MU2 which when Device Volume is selected equates to 92 in Roon.  On my system, using the Device Volume setting in Roon produces a more forward presentation but very detailed.  The Fixed volume setting in Roon on my system produces a wider and a bit less forward presentation but still preserves the incredible detail that the MU2 produces but with a more natural and engaging sound to my ears.  I have been flipping back and forth between the 2 settings.  I do like the Device Volume but it is more HIFI sounding on my system than the fixed volume.  Give it a try on your system.  I am not sure why there is a difference between the 2 settings but there certainly is on my system.  I am running a Trafomatic Rhapsody integrated amp and Wolf Von Langa Ultima 12739 speaker.