I had the same experience as OP's with my KEF Reference 1s, they sounded great for jazz and baroque, but less satisfying for large orchestrations than the KEF Reference 107/2s they replaced. So I carefully went through the setup of the Velodyne SMS-1 bass manager and the pair of HGS-15 it manages, changing all the cables AND resetting the crossover from 40 to 80 Hz. Magic happened. The setup is as satisfying as ever for jazz and baroque, but now also has the spacious soundstage for large orchestrations. A Mahler symphony sounds grand again.
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