Be thankful for JSTOR. One of the subscribing universities and institutions should be able to provide your needs.
A quick glance shows that ASTOR provides 22 journals with 'music' in their titles; of course others would occasionally have music as subject articles.

For current issues of scholarly journals, Project MUSE provides some 250 online to subscribers. Also non-profit, the service, guided by Johns Hopkins University, must charge. It is hard to conceive of these services ever being provided without charge because of the costs of materials and personnel.
http://muse.jhu.edu
(Accidentally noticed that one journal available from this service, "Callaloo" (African-American writing), currently was carrying a two-part study of Hip-Hop).

There are other such services that restrict themselves to particular fields, e. g. Chemistry and Physics. All charge for their services.

Of course if the U. S., etc. stopped waging pointless wars, perhaps taxpayers money could fund these enterprises rather than armaments and soldiers.
Until that Utopian day, don't expect nothin' fer nothin'.