Music is heard not only late at night, at the tiny bars which take over the streets in summer and the meyhanes, but at all times of the day, especially on the weekends. One of my favourite films, Fatih Akın's İstanbul Hatırası: Köprüyü Geçmek (Crossing the Bridge: The Sound of İstanbul), has an entire segment on the sokak müziği - street music - of the city. Akın follows the band Siya Siyabend in what is probably my favourite section (and favourite scene!) of the movie. I remember downloading a bunch of songs off their website (available free), immediately after I finished watching the movie - they have been a perpetual feature on my playlist since.
The sokak müziği band I absolutely adore though, is one called Kara Güneş (MySpace page here). I have been listening to them for what feels like eons now (my mom loves them too!), so it was a huge, unexpected thrill to chance upon them performing on İstiklal on my last day in the city. I happily plonked myself down on the ground listening to the music, clicking pictures and having a brief chat with some of them during their break - they were, I think, somewhat amused that I knew of their existence. Of all the music discs I bought in İstanbul, theirs is the one I love and treasure most - all fantastic new stuff I hadn't heard before, with lots of santur.
For anyone even remotely into music, the sounds of İstanbul are truly worth exploring. Akın's movie is great introduction - go watch it now! For people too lazy to get the DVD, the movie is available on google video, albeit with pretty random subtitles (the very first line has Confucius turned into Cumfukius). To listen to music on the Kara Güneş or Siya Siyabend sites click on 'Diskografi' and then 'Dinle' for whichever song you want to hear. To download, click on 'İndir' and then right click and 'Save As' on the 'Link' that appears. Enjoy, and tell me if you liked.