Background
One of my best Macs was my iMac 5K. It was the first time I'd bought an iMac (having previously had over 15 years of PowerMacs towers from the G4 through an Intel model). I'd suped it up with a lot of RAM and upgraded to a 1TB SSD. The display was the most magical part, and despite being from 2015, it has served me as my Roon server after I retired it from daily service.
On the iMac performance started to lag heavy. Despite it being a quad-core i7 chip with 16GB RAM, using the main Roon GUI app was not working anymore. I changed to the Roon Server, which basically runs headless. I was having to restart Roon from time to time on the iMac as the memory usage exceeded 5, 6, or sometimes 7GB.
Right around Christmas 2024, my Synology NAS died. It was a four-bay unit and since buying it, it had been rock solid. The drives were in tact, so I simply moved them to a new unit. My new unit was the DS923+, which comes with RAM upgrade and SSD options. I first installed the unit by replacing my old drive array and after some start up and upgrades, it was running. This time around I made use of both Ethernet connections to my Gbit router. Either because of the Ryzen processor and/or the double ethernet configuration, I noticed that things loaded and copied much faster from my MacBook Pro on the home network. Yet, I knew if and when I upgraded the Synology that I'd like to run the Roon server on the NAS. The NAS had originally been purchased to hold my music collection so that I could use Roon across the house to various endpoints.
Running Synology on the NAS
So, first, Roon won't appear in your Synology packages. This solution is one way to get the software on your Synology, plus some other NAS brands as well.
My DS923+ came with 4GB which is probably adequate for basic file sharing, and indeed, out of the box, it worked fine for my needs. However knowing the RAM requirements on my iMac, I chose to upgrade with a pair of 8GB RAM modules for 16GB of RAM. Knowing that someday I might want to use additonal Synology packages, I decided I wanted to do this once. I recommend filling both slots with the same brand and size of RAM, so do 4/4, 8/8 or 16/16.
A lot of folks recommend running the database off an SSD. Since the Synology 923+ accommodates two SSD drives, I purchased a 1TB model to accommodate my Roon Database. The SSD can also be used instead as a cache to improve its throughput. If you plan to use the SSD option for the biggest impact, you'll want two of the same size to accommodate the read/write cache over the basic read cache. The Synology manuals will highlight the upgrade options for your machine.
Synology recommends their own brand of memory and flash storage. They come at a premium price. Amazon reviews suggest that folks are satisfied with them, however I decided to try some cheaper alternatives. I sources both my RAM and the SSD from Otherworld Computing, from which I order a lot of my Mac accessories.
Installation
I shutdown the Synology and then removed the cords and then removed the drives. Inside I removed the 4GB RAM chip and installed the two 8GB chips which I purchased from Other World Computing. Then I turned it over and installed the single SSD. It too was purchased from OWC.
After rebooting, the memory was registering and so was the SSD. However, I found I could not configure the SSD as a volume as it was not Synology-branded. I was able, however, to use the SSD as a read cache. If I want the performance boost of running the Roon database off of a SSD, I need to purchase a Synology model.
Next, I backed up my Roon database on the iMac. Under Settings, it's easy to do an export. I then moved this to the NAS on the spinning disk array.
I then turned on the Roon-on-NAS package and then used Roon on my MacBook (which I use to listen and connect to the Mac server) and chose the new Roon Core it detected. After signing into Roon, I had to disconnect my connection to the iMac instance. Then it started to index everything and I went in and stopped it, so that I could load the copy of the database instead of building a new one.
The benefit is I get to keep my "records" of the playback from the original library.
Then I noticed all my music was from Qobuz, none of my own tracks which were stored on the NAS appeared. I had to remap to the folder where the music is stored, and then it came in.
In so doing, I lost my playback data from my local music of ripped CDs. I am wondering what re-loading the database now might do; I don't think it would help as the (old) path to the Synology, mapped from a shared volume on my Mac, would be replace the new mapping.
Ce la vie. I also had to re-add my endpoints by clicking "enable" for the ones I wanted to use.
The Synology is now running at about 60% CPU and the Roon app is taking about 5-6GB of RAM to run. Despite not running off of an SSD, the Roon app's response in scrolling through albums seemed quicker on the MacBook.
Lessons Learned
Perhaps I should have bought the Synology SSD instead of the one from OWC. The OWC unit was cheaper and with more storage (1 TB). At least for now, I will monitor any benefits of using it for cache. I don't use the NAS for a lot of file transfers, but I've already noticed before installing the SSD for cache that scrolling through videos in the Synology Drive app on my iPhone was a lot quicker. I owe this to either the faster processor in the 923+ or also the use of two ethernet connections.
The process of upgrading the RAM and installing the SSD was pretty easy. Just note how the old RAM comes out in terms of the where the notch is and you'll be fine. The SSD was a little tricker, managing the angle at which you insert it, but once in, it easily snapped into place.
Over time I may decide to change up my photo storage to utilize Synology Photos. Right now I use a Thunderbolt drive to serve my Mac the Photos library, using Apple's Photos app both for management and basic editing.
In terms of a Roon solution, having an upgraded NAS with the processor and memory has thus far worked fine. I'll update this post if I find any contrary evidence not to suggest using a Synology NAS as a Roon Core server.
Update
After all my music was imported, I found that the performance requirements changed. Listening to a Qobuz album, the Roon server process on the NAS is taking between .6-2% CPU. This is outstanding compared to what I'd experienced on my iMac. The memory requirements are higher, at 7.5GB. This after a runtime of 1.5 days. Playing back CDs ripped to the NAS increased the CPU to 12%, which then went back down, presumably after the album was cached onto my MacBook running the Roon software. Based upon my experience, I'd recommend 16Gb as the minimum requirement for RAM and might go for 32Gb if you can swing the cost.
The Synology 923+ has a 2.6 GHz AMD Ryzen R1600 Dual-Core processor and comes default with 4GB RAM.