@andynotadam I assume you’ve tested both in your system since you mentioned the MU2 is superior. Can you tell me about the differences between them? Currently, no dealer in Norway offers the Grimm MU2; I believe the closest is in Sweden. I’d really appreciate the opportunity to borrow an MU2 to test before purchasing it."
Amps like every other piece of gear need time to warm up before sounding their best. I find the BHK 250 takes close to an hour to stabilize.
DAC’s can take even longer, which is why I leave them on all the time.
When I leave for vaction I unplug everything, and I find it can take close to week before everything returns to normal.
The MU2 is simply the most musical network player that I have heard. It beats my previous combo of Lumin U2/DS MK2/BHK pre easily. It is also much quieter. Frankly, it is superior in any category of audiophile descriptions that I can think of. The superiority was apparent on the first day too, which means it is just that much better.
I still use PST/MK2 for playing discs. Using MU2’s pre, I felt the SQ from playing discs is elevated too. So, MU2 is at the top reference level for its individual function that can compete with the best of separates.
So are most using the MU2 to stream music from a service.or from music you loaded on MU2’s own harddrive? And is one better sounding than the otber?
I subscribed to Qobuz and Tidal, but I also saved all my CD’s file into MU2’s internal SSD (mine has 8TB). I purchased on average 30+DSD256 downloads per year as well. So, I personally listen to all of them.
The CD playback from MU2’s SSD is as good, if not better, as playing physical discs. Therefore I do not use PST/MK2 that often, and a few times a week I use the combo to play SACDs.
More users are use it for streaming I am sure.
Both. Though technically, playing music from a usb flash drive inserted on the back of the MU2. Am also using my MU2 to perform the d/a conversion of cd’s that are on a player used as a transport via digital output to the MU2 digital input. I used to think that cd’s had much better sound quality than the streaming function, but since upgrading interconnect to Front Row Reserve, I no longer feel streaming to be of lesser sound quality. Regarding DSD256, they sound nice from the usb flash drive. Technically better than streaming, but depends more on the quality of the recording.
I do have a subscription to Qobuz for access to music, which is then connected to the Roon inside of the MU2, of which I purchased a lifetime subscription to Roon since the MU2 runs on Roon.
At this point I’m not really interested in streaming music from a service, but I do like the idea of transferring all my disks to a harddrive, and possible ditching a transport altogether. I could potentially sell three components l’m currently using, PST, DSD MkI, and BHK pre, and put those funds towards the MU2. I’ve always liked the keep it simple approach, but wound up purchasing the BHK pre inorder to elevate the sound of the DSD DAC. Going back to two components, an MU2 and an amp really appeals to me. Eliminates an HDMI cable, two power cords, and set of ic’s.
Transferring all my cd’s to a harddrive though seems like a daunting task.
Any recommendations on how best to do that?
You are right about the daunting task. I transferred my 4TB files all by WiFi, and I have one of the fastest internet speed at home too. I think the transfer was on 10 plus hours per day, and it took a week to transfer.
I listen to music on the ssd in my Grimm MU2 and do not stream. The Grimm is a really special piece and every bit as good as you described earlier.
You can also plug an external hard drive into the MU2 and copy from it to the internal SSD. That worked swell for me.
I’m a newbie to computer audio, so thanks for the info. So i guess the first step is to copy my cd’s to my mac. What’s the best format to save them in? And so I’m understanding this cotrectrly, after all the cd’s are loaded on my desktop, they can be transfered via WiFi to the MU2?
dbpoweramp app. is the best one for ripping CDs as far as I know. I first saved the ripped files into a Samsung 4TB T7 external SSD, then use my computer (with T7 connecting to it) to do the transfer by WiFi. So, the T7 becomes my backup once the files were transferred into MU2.
But Al’s way will be much faster by using the USB plug on the back of MU2 to do the transfer.
Oddly enough, I used a T7 to do it.
@eral63 Yes, the Airlens, the Mk3 and the BHK pre were in my system when I got the MU2 (with Synergistic Research Atmosphere SX Euphoria and Galileo SX cables connecting it all up), and the MU2 replaced these PS Audio products all in one swell foop.
Cold out of the box, the MU2 sounded really bad compared to, well… almost anything, but certainly compared to the PSA gear it replaced, sounding thin and terribly closed-in, but going-in I was aware that the MU2 needs at least 200 hours of play until it begins to morph into its final glorious sound.
Or lack of a sound–the MU2 is to me, basically neutral and very transparent, though in no way analytical. I am hearing details I had never heard before in familiar music, yet they were unforced and utterly natural, the word organic comes to mind, but don’t take my word for it, you can check out the many reviews out there on the interwebs.
In his review of the MU2, Michael Lavorgna of Twittering Machines said it best, If you want to hear the best digital music reproduction I’ve heard by an obvious and distinct margin, you’ll need to find a Grimm MU2 to listen through.
But, by all means, make sure you listen to one that is fully broken-in and that has been switched-on for a while. I, like many of us here, leave the MU2 on 24/7…
You are right on this, the MU2 took a few days to sound great. It did not sound swell right of the box now that I recall.
Now I recall copying files from the external drive to the SSD still involved the network. It was probably just as slow. Never mind.
Oh, now I feel better already. 
Almost everyone who hears the MU2 seems to like it. I’ve never heard it, so I’m not here to break up the love-fest. However, there are three issues that have prevented me from becoming an MU2 owner: (1) being Roon only (so far at least), (2) having a preamp that may not sound as good as a really good tube preamp, and (3) high cost (if a buyer isn’t taking full advantage of all of the components of this all-in-one DAC, streamer, and preamp).
I have never been a Roon user, and I love the Innuos Sense app. I am not willing to dive into the Roon world and give up the advantages (IMO) of the Sense app in terms of sound quality, stability, and simplicity. I also like having a preamp that supplies a bit of “tube magic” to the sound of my system. If I weren’t using the BHK preamp, I’d probably look for something like the Backert Rhumba Extreme. In terms of cost, the MU2 looks like a pretty good value for an all-in-one unit, but when technology evolves, will I want to spend more to buy the MU4 (or whatever else comes next)?
But the MU2 is still tempting. Are my concerns unfounded? Should I dump my current biases and jump on the MU2 bandwagon?
No. You have everything figured out already. For you.
I was in your position not too long ago. I used the Lumin app and was quite happy with the full loom BHK setup. But there is no question that MU2 made me happier. The Roon core in MU2 sounds great, and I signed up for the lifetime Roon after the free 30 days (or two months I do not recall) tryout that came with MU2.
But I will not say that you must move into MU2 if you are happy with what you have, because there will always be something better in the future.
Spend more time playing golf while we still can, that is always more enjoyable (like the day after my birthday with an eagle plus a birdie at the last hole. I may not do that again, ever). 