I have been setting the resolution at 600 by 600 which seems to look best on the Beosound 5 screen.  I am only doing this when I have the CD and scan the cover myself.  When I manually scan the CD cover, I scan at a high rate and then reduce the size.

However most of the iTunes covers will look good.

ok thanks; that means I can use my cover with might have a better res than 500x500; 

regards elmar

600x600 should be fine. Larger is possible as well, however tend to consume a lot of additional disk space too

If you are missing covers, have a look at the following site:

http://www.albumartexchange.com/covers.php 

For a Mac program to support you to find covers, you could give Coverscout a try:

http://www.equinux.com/us/products/coverscout/index.html  

(I know, not the cheapest around, but which large libraries it can save you a lot of time)