Thiel CS 3.6 mid-range problem


I have a pair of Thiel 3.6's, with a Mark Levinson No. 336 amp plus Levinson pre-amp and cd processor. I also have Audience AU24 "e" cables and AR6T conditioner. My mid-ranges are blowing out frequently -- 3 times this year. This didn't happen until I got my Audience conditioner and cables. The volume dial of my pre-amp is actually set lower than where it was prior to installing the Audience equipment. I don't think this is a case of playing the system too loudly. Time to upgrade speakers? Anyone have a solution or an idea?
gapperis123
Are you powering your equipment on and off in the proper sequence? Meaning power amp on last and off first? And when you turn the power amp off, are you waiting long enough before turning off the upstream components to assure that the amp is no longer being kept "alive" by energy stored in its power supply capacitors, so that it can no longer amplify turn-off transients that may be generated upstream? That can take as much as a minute or so with some of the solid state amps that I have experience with.

Regards,
-- Al
Al, thanks very much for your advice. No, I haven't but I will start now! Question: should I power off the amp and then wait at least a minute before powering off the upstream components? Glenn
Hi Glenn,

Yes, I would strongly recommend doing that. The one minute figure, though, was just a guess based on my experience with other high powered solid state amps. I suppose that a good way of determining how much time to allow would be to play some music at a VERY low volume level, then turn off the amp and see how long the music continues to play for. It would probably be a good idea to make that determination for going into standby mode as well as for going into "off" mode.

What makes all of this particularly important with your equipment is that your amp is capable of delivering enormous amounts of power (in the vicinity of 1000 watts) into the 2.5 to 3 ohm impedance the speakers have throughout the mid-range region. So even a very brief turn-off transient from the upstream components, applied to the input of the amp while it is still powered up internally, could very conceivably put your speakers in jeopardy.

Best regards,
-- Al