Bass leaves after amp warms up?


I don't understand-after my Musical Fidelity M6i amp warms up for about an hour I notice the deep bass & kick drum aren't the same.
They sound less musical with loss of weight/depth.The notes are there but the moving of air have left.Sound is has much less impact and boreing.
I had the same problem with Bryston amp so there is no defect with amps nor with the rest of my equipment/
PSB Synchrony one speakers,AQ cables,Bryston CD Player.
My question has anyone heard similar & is there a plausable reason?
fishing716
I would keep power conditioners out of the equation period. The symptoms occur with system warm up. If anything the OP should be backtracking to find out where it all started.
"I would keep power conditioners out of the equation period. "

Agree. Once the issue with deteriorating bass/dynamics is resolved, then add it in gradually perhaps and see what might be had further from there. Power amp would be last thing to use with a conditioner and should be totally optional at that point.
04-17-13: Bifwynne
Al and Ralph -- take a look at the graphs at the URL above. I'd like to read your thoughts about whether a solid state amp, or any amp for that matter, would get indigestion from those impedances.
Hi Bruce,

Thanks for providing that additional data. Earlier in the thread I had linked to JA's measurements, which provide better resolution than the Soundstage graphs. Also, for some reason the worst case numbers you quoted from HT Lab differ from JA's, with his numbers being more severe.

In any event, IF the problem is amplifier-related I agree that the Zeros would be a reasonable solution, used with their 2:1 impedance ratio. Higher ratios would reduce the maximum amount of power that could be delivered to the speakers to significantly less than the amp's 200W/8 ohm rating.

That said, there are certainly a great many separate power amplifiers that can be expected to provide good results with these speakers, especially given that phase angles are very benign aside from the dip that occurs around 27 Hz. Although, of course, a suitable high quality separate power amplifier would most likely cost much more than a set of Zeros.

Best regards,
-- Al
I removed all cables today out of fustration,will reconnect w/o power conditioner.
Also feel it is doing something detrimental to the sound/dynamics
Plan to try cablepro revelation power strip with no filters
Props go to Tls49 for catching the conditioner issue.

And Bifwynne, looking at that impedance curve, these PSBs need some power to push them to their potential.