The differences you heard could very well have been the material being played. The 60s getting a better source(recording) than the Monitors so as to coerce people to beleive the Studio series is MUCH better than the Monitor series and spend more money, not that that would happen in a store
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In audio you have to have comparisions done as quickly as possible in the same room with the same source material otherwise the results are nearly meaningless, unless extreme differences are noticed, ie Bose to Axiom
