speaker problem

quick question
after months of problem free listening, when i turned on my amps and cdp tonight i heard a low crackling noise coming from my left channel, specifically the tweeter.
powered off and checked all connections, ics and speaker cables, and everything seems in order, nothing loose.
when the power amp is off, no noise whatsoever.
is this a sign there is something gone wrong with the left tweeter?

associated equipment:
rogue mag 99 pre
rogue 88 power amp
metronome cd1 mk1
msb link iii
alpha core ics
alpha core mi2 sp cable
ps audio 600

any thoughts? i listen everyday for hours and have been for months w/o this problem.
thanks in advance


did you try switching the speakers -- left to right and see if the problem is in the same speaker ...if so you may of blown a tweeter --- if not

I would check your Tubes in your rogue power amp --

they may be going bad -- the kt-88 can cause a straching sound when they are going bad ... have you check the bias .. on them ...br>
check our web site on audiogon for replacement kt-88
good luck
good listening
i will switch the speakers later today when i get the chance. btw, they are paradigm monitor 7's.
i suppose it is possible that my kt88's are fizzling. the sound is a scratchy, crackling sound, audible only when very close to and directly in front of the tweeter. standing up in front of it and you can't hear the noise. however, when i first noticed it, it was audible from my listening position. anyway, i bought the 88 amp used back in september and have clocked somewhere in the way of 700 hours. the tubes were said to have low hours since the amp was advertised with a retube. i trust the person i purchased it from. though 700 hours does not seem much even for output tubes, i suspect my psaudio 600 may have some part being played here. i believe i've heard some say the power plants can can excessive wear on tubes, have you heard the same?

thanks for the advice
i'll let you know how tweeter diagnosis goes.
Consider checking the tubes on your preamp by switching them over from right to left and vice versa and check if the noise transfers to the other speaker.

HI fujindemon
the tubes may have low hours on them ... but they were probably takenout -- shipped to you and put in --- tthey probably bounced around alot ....

and that is a good idea fromRmml --- try switching the tubes on the amp from left to right and also the preamp if the amp had no effect ... remember-- if you do not switch them back you need to rebias ....

probably a good idea after all is done just to rebias everything

agree it sounds like a tube failing...
What happens when source equipment is shut off & just the power amp is left on? That will help to locate the culprit / eliminate some of your variables in the puzzle.