I'd be inclined to avoid the marathon singaround in the Rifle Club, if I recall correctly. The few times I've been in there, I've heard some appalling rubbish.

The other official singarounds are usually much better, especially if they're led by a guest who knows what he or she is doing. Venues last year included the Dolphin, just by the bridge and a pub whose name I've forgotten, which is over the far end of the bridge and turn right.

There are also various unofficial sessions, the quality of which can vary enormously. In particular, there's a pub opposite the bus station, which has some sort of trendy name; The Tap and Spile or the rat and parrot, I think.

Sorry to be so vague, but the brain cells have all retired to the old folks home and refuse to work anymore.