1. a left/right bounce where the tune jumps around in space. I find this positively painful, so the only solution without additional processing is to narrow the source stereo recording.
2. in spite of the above, a really localised sound. The more you echo-proof your recording space the more this is true. It's realistic... but not actually particularly engaging to listen to, and I've not yet found a good way of widening up the sound without causing other problems.
So - I had an idea that using one mic in front of the concertina and one mic behind would pic up the same sound but with different details, so would get interpreted as a single wide source. Here's the setup:

The sound gets attenuated by the player so the rear mic (right channel) needs to be increased, but the idea definitely works - a simple stereo mix (with no reverb etc) has a nice wide sound with no disconcerting jumps from left to right.
I'd like to hear comments on this (does anybody else to it?) or ideas about other ways to get the same effect.
Here's an example (with a bit of reverb and equalisation) - a Frédéric Paris tune called Ganivelle, with improvisation/doodling.
http://www.rowlhouse.co.uk/concertina/music/GanivelleImprov.mp3











