I would like to use solid core 2.5mm mains cable (6242Y) for speaker
cable runs in plastered wall, but I am concerned with how practical it
will be to terminate.

At the speaker end, I hope that I can simply pinch the cable core with
the speaker's binding post. At the other end will be a wall plate with
binding posts (e.g. http://tinyurl.com/a3uay ) for the amplifier
connections. On the rear of this wall plate, I guess that I'll have to
solder the core to the hidden end of the binding post.

Soldering solid-core untinned copper is not easy. Can anyone suggest an
alternative solution (e.g. is there a wall plate available with binding
posts that have screw-down connections behind the wall plate) ?

How have other people tackled the problem of terminating solid-core
wire?

Thanks!