Carver Silver Edition efficiency question

Several years ago the ribbons for my Carver Silver Edition speakers were rebuilt by Dave Sauter at Carveraudio.com. He did a fantastic job!! The speakers continue to sound great but I have one question regarding their performance. One speaker is just a little less efficient than the other, in ribbon output. This can be noticed when listening to music, the balance is off slightly. By changing balance, increasing drive to that speaker, the balanced stereo presentation is restored. This is definitely the speaker. To test, I have completely changed all equipment (McIntosh), amp. preamp, substituting different speakers in the system, measuring output from the power amp, etc.. It is clear the output from the one ribbon is slightly decreased as compared to the other speaker. This issue seems to have been developing slowly over the course of some time. It now takes about .25 watts more to drive that speaker to produce a balanced output.

Is it possible this imbalance is due to deteriorated capacitors in that speaker's crossover? Would it help if I rebuilt the crossovers?

Have you tried swapping them, left to right to see if the problem follows? If it does, then I think rebuilding the crossovers would be a good idea. Let us know.

Yes, I have swapped the speakers, left to right. The decrease in efficiency did follow with that speaker. I am going to rebuild the crossovers as soon as I get a chance and I will be posting the results.

Before messing with the x-overs, try swapping just the ribbons in each speaker. If the problem persists in the same speaker.. then its probably the crossover, if the problem switches over to the other speaker, then it might just be the ribbon.
How long ago were the ribbons rebuilt ?

James

Hi James,

Thanks for the suggestion. I will try swapping just the ribbons. They were rebuilt Sept. 1999.
Gary

I finally took the time to reverse the ribbons. There was no change; the slight decrease in efficiency remained in the same speaker. Obviously the origin of the difference must be somewhere in the crossover. Since the speakers sound wonderful and identical in all other respects I am not going to pursue the issue into the crossover network. Thanks for the suggestions.