You can see the complete hierarchy when opening the main browsing via ´Genres´, open a subgenre, go to Editor mode and choose ´Parent genre´:
Note that this genre structure is roon´s own hierarchy in full (sourced from TiVo I guess) plus the ones your core has created.
It is also a useful tool to put genres accidentally created by some album´s tags to the right place. In my case, ´Progressive´ and ´Beat´ turned out to be top-level genres so I have moved them to the parent genre Pop/Rock.
In know that, I thought there is a document somewhere (more convenient for reading) showing the default hierarchy. But maybe not
Can you clarify what you mean by this? I’m not quite grasping what you are getting at. Do you mean that on his Artist page, you do not see his complete Discography (with 59 albums by him, 20 Singles and EPs by him, 13 appearances and 389 albums of his compositions)?
That should not be if this someone is really a composer whose work was interpreted by other artists on their designated albums. You might want to double-check that roon is filing this composer as a ´Classical composer´. Funnily this seems not to be the case for some like John Williams who does not have a ´composed by´ section by default:
So you have to manually make him a Classical composer using his Artist Editor:
And - voilá - he has become a composer with full right of having his ´composed by´ section:
In this case I did not understand why this is, as roon seems to file John Williams as a classical composer as it does with classic example Leonard Bernstein who still retains his main albums and appearances section:
Maybe there is another reason for that: In case a composer is assigned as an artist or primary artist to an album at the same time, this album is NOT listed under ´composed by´. Or in other words: If a composer is taking part in all his albums as a musician, producer or primary artist, he or she does not have any albums to list under ´composed by´.
Your example applies to metadata being sourced directly by roon (Tivo and MusicBrainz) plus whatever information roon gets from Qobuz (which includes who is counting as a primary artist and who not) for this particular album.
If the OP has that album ripped in his local library, roon will mix Tivo/MusicBrainz metadata with his local tags which might differ from Qobuz´. So easily a composer can be listed under primary artists making the album disappear under ´composed by´ with one method while with the same album sourced from Qobuz everything might be fine.
@Jörgen did you try checking the details under the assigned composers and artists of the album in question? If for example Yann Tiersen is listed as a composer as well as a primary artist or performer, roon might run into contradictive metadata issue.
In this case with Bernstein it worked but the album is solely shown under ´Appearances´.
Welcome to the funny farm 
A few comments as I read through the thread , many already made but it doesn’t hurt to re-emphasize
One obvious check is to see that the album name (does your ripper add CD1 after the album title for example) is the same for all tracks , also any disc # or even disc names. Also you sub folders per CD must be CD1 … CDx not other text that will immediately cause Roon to assume a separate album and split it off.
For albums not showing up , they may be duplicates or versions of an album already in the library so will not show in the just added area.
I have not read the full thread yet I will but I need more coffee but I am sure we can sort you out .
Keep posting examples as that is the best way to spot inconsistencies
Also the advice above of checking how many are IDed is vital ,if Roon can’t ID an album it cannot create it’s interlinks . As an example I have less than 100 not ID’ed out over 5000 albums which is 60% classical.
BUT there are no standards so difficult to manage
This dates back to the bad old days where there was no Tag for Composer as standard so the RECORD LABEL chose to make [Artist] = Composer and [Album artist] = actual performer
Not a good idea unless its a 20th century composer who is actually PLAYING his own music , see comment above. If needs be create a Custom Tag for [Composer] inyou raw files .
this will cause Roon to wobble … 
Box Sets deserves special mention , especially if they are a large component of the library
Basic Rule - leave box sets alone , they are an album in their own right so
If you do this then Roon stands a chance of ID ing it as the box , as soon as you break these rulkes, Roon will fail to ID then you will lose interlinks , credits etc . Roon depends on ID to add its additional metadata
We are led to believe that Roon is currently working on a proper solution for Box Sets so watch this space but leave them as a box because that’s what Roon is expecting
You can then use the Focus and Filter tools to dig into each box for what you want
For reference ALL my box sets are ID’ed by Roon and there are quite a lot so it is doable.
Any difference in the tracks in the value of album or album artist fields is likely to break these albums up. If the albums are multi-disc some applications add the disc number or name to the album name and this can mess things up, and its important that each disc is in a seperate subfolder under the main album folder.
Credits are complicated, usually for classical albums yould need the composers to be stored in the composer field only rather than the album artist or artist fields. The album artist should usually have the conductor (if applicable) and main performers, artist field is similar but for the track.Some taggers add the performer and role to a performer field, but this can cause problems for Roon because it doesnt expect them to have a role part. Another issue is that roon can handle multiple values for album artist and artist fields but some editors just store multiple artists in a single field.
You could take a look at my SongKong tagger this has special mode for tagging for roon compatability and can tag any number of albums with complete control over what metadata gets modified.You will get better results in roon if you run your music against SongKong first.
The free Lite version is a useful tool for identifying any issues with your metadata because you can run a over a folder and it will show exactly what metadata is stored in the files. If you would like to run it against some of your problem albums I can probably tell you what the issue is.
As I said earlier, Roon does recognise cases where composers are performers on albums - Bernstein and Britten being prime examples of this. In the early days of Roon (circa 2015), this was not the case, but it was fixed a long time ago.
@Arindal - Yup, I think you’re correct - the “Composed by” section will only appear for composers that Roon considers as “Classical” composers… That’s probably the deciding factor.
AFAIK, Roon doesn’t actually use any metadata directly from Qobuz. If an album is identified, then Roon will use the metadata it has in its Cloud database, which is sourced from Tivo and Musicbrainz.
Okay but I wasn’t taking roon specifically here, in general you should not have the composer as the primary performer unless it is a modern composer e.g Michael Nyman and hence actaully involved in the album
Agreed, and that’s what I had said.
For a smooth roon experience this seems to be a healthy ratio.
The other question is why still 100 albums are not identified. That is surely differing from library to library. Some might not exist in roon´s two metadata sources, particularly if they are bootlegs, private/micro-label releases, re-releases from the analogue era, promo albums, DJ sets, samplers which have not been released worldwide or anything like that. Funnily I have a bunch of such albums released by theaters, church organizations, hi-fi manufacturers, book clubs, cultural sponsors and public broadcasters. The latter is the most surprising thing in my eyes, but entities like the BBC, BR, WDR or SWR seem to ignore the metadata question. Examples:
In my experience a lot of unidentified albums can actually be made identified by some detective work. That is particularly true to albums having sets of metadata being crowdsourced to MusicBrainz using non-standardized or plainly wrong album or primary artist´s names. You have to manually figure out both to point roon to the correct set of metadata. Example:
After ripping that album, the primary artist was ´Renner Ensemble´ and the album title ´Reger, Wolf: Männerchöre´ bringing roon not only to leave the album unidentified but not showing any matching set of metadata during the manual identification process.
That is correct, roon would not take over Qobuz´ metadata for identified albums as it would do with local files. Nevertheless it will take album title and primary artist´s name sourced from Qobuz into account when it comes to identifying the album or matching credits.
Ripping multi disc sets:
I use the following naming string in dBpoweramp:
[IFVALUE]album artist,[album artist],[IFCOMP]Various Artists[IF!COMP][artist]/[album]/[IFMULTI] [disc]-[track] [title].
It deals with single discs and multi disc box sets.
With box sets I give each disc the same album name (name of the box set) and identify the discs as 1/4, 2/4, 3/4 and 4/4, for example.
I never have any problems with multi disc sets and I hope this is relevant and helpful in the context of this thread.
The squares above are supposed to be open and closed square brackets
I checked MusicBrainz database and as far as I can see this album is not in MusicBrainz therefore the incorrect data is not coming from the album being incorrectly entered in MusicBrainz. Perhaps you mean the ripping tool you are using is incorrectly matching to the wrong album in the first place, and that is why the metadata is incorrect.
The non ID is simple, I don’t practice what I preach. As Roon’s box set handling is so poor I have split the odd box into original releases. The 100 are some CD that aren’t actual releases or are no longer current
That’s why I say don’t split, I know from experience it doesn’t work
I live with them , the original boxes I keep in an alternative folder but disabled waiting for the day box sets become a first class citizen JRiver still has it’s uses
You are right, the metadata plus misleading primary artist and title seem to be coming from TiVo. It is pretty unlikely to have data for a ripable album lacking all track information coming from MusicBrainz as they would not allow such incomplete set (vinyl rips being an exception).
@Mike fully agree to what you were writing. Just wanted to highlight that there are numerous reasons to have a certain number of unidentifiable albums but in most cases it is simply some manual work in roon to get >95% of albums identified.
Yes I agree , I did not get to 100 / 5000 without a fair bit of manual grooming . That said Roon probably got me to 300/5000 .
Messing with splitting box sets does not help , that’s the point I was making . A box is an Album , let it stay that way unless you REALLY gurantee that its all single releases
Now knowing how to find the unidentified albums in an easy way, I am working with making them identifyable, and it sure looks like adjusting the metadata to be more understandable for Roon helps for some albums.
Of course, I also have promo, demo, magazine, etc. albums, which by large have not been ripped yet in FLAC format (and I have detached the old MP3s of them), so I do expect those to give problems.
But there are still some that are actually mainstream albums already ripped that are not recognized, and this will then, as you suggest require some detective work. An example here:
One was withdrawn from the publisher (but is part of a series of two, both withdrawn, where the other indeed has been recognized):
Others are local publications that do not seem to be registered in the big metadata databases, even if they may have sold in large amounts locally - an example from Holland here:
But some may be local productions (like this one from Germany), but still - having sold in large amounts during several years and to be easily found in Discogs, which is my goto-site for information:
Then, as expected, there are some with nature sounds and other special things, that even have been published under different names, often without any artists mentioned - one of those:
But then there are the mystical cases that really should be recognized, such as:
Actually, even more mystical - some were not identified at first, but when I try again, they are immediately found. Why do they need a second search? Here is one of them, now identified:
Nevertheless, I have just under 200 less, having fixed maybe 30 or 40 already, so I am confident that I will end up with 100 or less (but this is before ripping the expected problem albums - especially such that have no text in latin letters, which traditionally are difficult to find anywhere), which are from, e.g., India, russia, or Denmark, or which are such as sampler CDs or never-published demos sent to me by the artist. Probably, a fair goal depends a lot of the nature of the collection 
Sounds clever, in theory, but if that means that half - or all - of a composer’s works are not represented on the composer’s page, then it is not suitable for at least my needs. I want them all there, and it looks like this requires, for some composers, to add them as primary artists, even if they didn’t have an active role on the album.
An alternative could perhaps be to tag the albums with the composer’s name and this way create a complete “shadow composer” universe with all the albums correctly marked under each composer. Sounds like even more work, so the lesser evil will then be the primary artist model.
