Library catalogs do not generally index the contents of periodicals. A catalog will usually tell you what periodicals a library owns, and perhaps which issues they've received, but it will not tell you what is in those issues. To get detailed access to the contents of periodicals, you need to use indexes to periodicals.
Please note that some of the most important indexes here can be searched simultaneously. This is very easy to do with Music Index, RILM Abstracts, and Academic Search Complete. From the search screen for one of the databases, click on Choose Databases and select the databases you want.
The important periodical indexes for music are:
International Index to Music Periodicals
General indexes can also be important, particularly since the music-specific indexes tend to take a long time to add current content, so they can be several months behind. Here at B-W, the most important general indexes are:
Academic Search Complete
OhioLINK's Electronic Journal Center
There is also one retrospective index to music journals that may be important for older historical research, but which we do not own in any form at B-W. That is: