Following the addition of Squeezebox support, I am about to take the plunge and install Roon on my Mac Mini. It will replace the Logictech Media Server that currently drives my Squeezeboxen. I will also no doubt be removing the Plex server that also runs on the machine.
My music library is stored on an external (FW800) RAID array. I also use the same library for Internet broadcasting. The software I use for this purpose (MegaSeg) is capable of writing to the file metadata tags - for example if I find an error I can fix it.
I don’t necessarily want more than one application updating my tags, unless I can determine how/when it occurs. However, my expectation is that Roon will do a much better job of maintaining accurate tags than my current system for ripping CDs (dBPowerAmp) and online file download suppliers.
Can Roon be pointed at the library as a Watched Folder and only update its own database while leaving the files alone, or will there be problems with two apps accessing the same audio files?
Assuming that Roon does a much better job of maintaining the accuracy of audio file data than at present, is there any way I can update the metadata in the library audio files from Roon on an album (or other manual, non-automatic) basis so that I can control what is written to the tags?
Using a watched folder will not touch your files in any way. Anything that you see or change in Roon will be managed only in the Roon database.
There are no functions to update your file meta data with Roon meta in your watched folders.
You could export your library from Roon to a new set of files. You have to be very cautious however as Roon is not fool-proof. In other words, errors do exist in data from meta providers, Roon can apply the wrong version of a CD e.g. get some bonus tracks wrong, etc. You are not guaranteed to get 100% error free exports unless you have verified all data that Roon presents.
So, in short, I would recommend keeping your basic file meta for track title, number, disc number etc correct using whatever tools you currently use. This will give Roon the best chance of hitting a good ID.