saying hello and a seemingly simple problem

[Starson]

Hello everyone
I am new to this forum and need your advise.

Don't know if you're familiar with the Rokone speaker but it's a 2way, 100W 8Ohm, bi-wireable bookshelf, x-overed with the simplest L-RC filter. the seemingly simple problem, is that the left channel's audio volume has become about 2/3rd lower, it's more noticable on higher volume levels, changes logarithmically and varies in time. centered on mid Freqs (<1KHz~>3KHz) as the unit gets warmer the sound quality deteriorates but both high and low freqs are affected. i've switched the speakers and checked the signal path but the problem remains.
apparently the x-over parts are ok and it's the mid-base driver. they're matched and paired with their tweeter in factory but could it be a faulty cap or resistor? showing more resistance on high currents and fooling the amp into seeing more impedance? isn't it wiser to upgrade and replace the whole thing with Scanspeak or Vifa? any suggestions? i truely admire the sonic (not built) quality of the original ones, but don't know if they're still available.

Best Regards,
Starson

[roddyama]

Starting with the speakers, start swapping left channel to right. If the problem stays in the left channel keep swapping parts moving your way back to the amp (speaker, speaker cables, crossover,...). If you get to the preamp and the problem hasn't swiched channels than it's time to break out the schematics.

[Conrad Hoffman]

That's odd. Usually any type of connection problem will show itself as noise crackling and breakup, not a tonal and volume change. It would also be unusual for a crossover component to do that. Maybe an electrolytic going bad? Are you absolutely sure it's the driver?

[Starson]

Thanx Rodd, I did swap them, also cleaned and switched all the cables and interconnects but the problem follows the speaker. and yeah.. breaking the last part would be so painful since i dont even have them (in black and white thanx for reply.

Thank you Conrad, yes, very odd indeed. there's not even a noticable distortion, just a curve on the freq responce, esp on vocal tunes range. you think the RC part's gone tricky? funny thing's that it's so unstable. but definitely hit-current-time related. the impedance doesn't match and reads about an ohm higher on the left input. i also suspect the tweeter.