Kev. I was just thinking that too. I can see it's one of my weakest link in the chain as well. Hopefully I can try the one of Allnic preamplifier next week and Shindo as well.
A Shindo preamp is a great way to get started with the brand. Compared to your existing preamp it will take your system to a whole new level.
So many times people focus on the amps and forget the preamp is the 'quarterback' of your system. The Monbrisson is Shindo's very popular mid range preamp.
Great value, good phono stage and a great way to upgrade without breaking the bank.
Will work well with your 275's. Truth be told you only need one 275 in your system with the Tannoy's. When I had 275's I actually preferred the SQ running just one.
It is after all designed as a stereo amp, it just gives you the option of using it as a mono's.
75 watts of power (really 90) is plenty to power your speakers and take advantage of what McIntosh really designed that little 275 to do.