Sec. 10-1.3 Permits.
(a) Required. Any person using the recreational and other areas and facilities under the control, maintenance,
management and operation of the department of parks and recreation shall first obtain a permit from the
department for the following uses:
(1) Picnic groups, consisting of 50 or more persons;
(2) Camping;
(3) Sports activities conducted by either a league, organization, association, group or individual;
(4) Recreational activities, including nonprofit fundraising activities, sponsored by community
organizations, associations, groups or individuals;(5) Meetings or gatherings or other similar activity held by organizations, associations or groups;(6) Nonrecreational, public service activities, meetings and gatherings held by organizations,
communities or groups;(7) Right of entry into parks for installation of utilities or construction work;
(

The playing of musical instruments as solo or two or more instruments which fall within the
standards described in paragraphs (A), (B) and (C) of this subdivision:
--- Sports activities is not defined, neither is the size of a group (many states do define these terms). While frisbee might not be a sport, it would be a recreation activity and would fall under (4).
(off topic!) I didn't know this, but found out yesterday, do you know you have to register bicycles with the state and pay 15 bucks!