First, I offer the Globe on Morning Lane, Hackney. I believe that it is an old boxing pub (whatever that may mean). I go on a Monday night from time to time (when I can find somebody to go with) to listen to the RnB being performed by a variety of musicians, but in particular John Parry and his three sons. He also goes under the name of the Memphisallstars, sometimes appearing on a Friday night. Wednesday night is crooners' night and Jazz is apparently played on a Sunday afternoon. An added attaction is decent beers such as Fuller's London Pride and Young's Bitter (the latter selling at £2 a pint) alongside the less savoury lagers. It's a very friendly place and deserves to be supported.
Here is a clip from a Monday night (taken by myself, of course):- Place cursor over upward arrow at bottom right hand side, after clicking on the 'play' button and click on 'HQ' when it appears, to greatly improve the quality of the recording.