S75 is a closed box design, M150 has bass ports. I doubt there will be a big difference in the bass frequencies.

Plus, there is more to life than woofers!

S75 is part of the 'audio' range of B&O loudspeakers, M150 belongs to the top of the line 'monitor' range.  For the higher frequencies you will probably be better off with the M150's. They were the best B&O had to offer in their time, save maybe MS150's (although those are the same except for addition of a subwoofer). Also S75 are an older design.

I used to own S75. Nice sound but the M100's I use now are vastly better: the sound has more depth and realism to it, S75 were a bit flat and emotionless. This is the difference between the S and the M series!

Sort of agree! I too have had S75s as well as MS150s and now M100s. The S75s did me for many years - I bought a pair new and used them with a BM2400. Lots of bass but not brilliantly controlled or detailed. Very good for parties! The MS150s are much more controlled and detailed in the bass as are the M100s. You do need a big room for either of these though. In my experience, the finish of the S75s is better than the later MS150s but not as good as the M100s.

Peter, one more post to go!

Beofan53 wrote:

Peter, one more post to go!

Well spotted.

Ok Peter what are you going to do with this important post number ?  :-0

This will make you laugh - one of my moderator colleagues deleted it!! (By mistake I should add!) 😁

Peter wrote:

(By mistake I should add!) 😁

...just have to start again then !  :-)

Thanks for the feedback, hadn't considered some of these points --

H