The Sony I mentioned earlier has 3 pre-set sound modes; only 1 of which is heavy on the bass. You can also adjust the traditional bass, mid and treble using a phone appLot's of good ideas - thanks gents.
I had a Tivoli One (before it was called Tivoli) 20+ years ago - I wonder where that went? Great sound but it was a FM only m,ains powered unit so even if I could find it...
I think I'll look into waterproof bluetooth speakers and use my phone. That seems like the best solution to this.
Now I need to find one that isn't BASS Extreme!