$ curl -i -m 1 http://rr.fmtuner.ru/ 2>&1 | awk '/^Content-Type:/ { print $2 }'
audio/mpegcurl -i -m 1 http://rr.fmtuner.ru/download.mp3 и получаете Content-Type: audio/mpeg
$ curl -I http://provisioning.streamtheworld.com/pls/KALCFM.pls
HTTP/1.1 200 OK
Date: Tue, 17 Feb 2015 11:39:06 GMT
Access-Control-Allow-Origin: *
Cache-Control: max-age=0, no-cache, must-revalidate
Pragma: no-cache
Expires: Thu, 01 Jan 1970 00:00:00 GMT
Content-Type: audio/x-scpls; charset=UTF-8
Content-Language: en-US
Content-Length: 263
Connection: close