UPDATE: Yesterday I walked by the aforementioned DISCOS KRISTEL on Calle Bordadores, 11 (just barely off of Calle de Arenal) and IT SEEMS it's closed for good, with the white paint covering the windows and everything. I peeked in and could see all kinds of shelving strewn about. The outside sign is still hanging there so maybe, if we're lucky, they're just going through a re-decorating period or something.

Discos Yunke is still open, however.

Saludos, MadridMan