Help with kef r900 issue

Good idea. I’ll give it a whirl. Thanks

 I dont understant . the issue coming from both speakers or just one ?

Both. Initially, I thought it was from one, but may have failed to isolate the other. Who knows, but I’ve now tested each in isolation, under identical conditions, and found the effect nearly, if not identical. 

Maritime we are a long time Kef dealer, there is no way that if you replaced a set of drivers and the speakers are making the same distortion is it the drivers.

You may have a bad part in the crossover or there is something wrong with one of your components.

The likelyhood of both speakers having an issue is doubtful you need to go back and start checking your components.

I would borrow an amp and start there.

This is one of the reasons why buying direct is not a good practice if you have a local dealer then your dealer would be assisting you to resolve the problem.

Dave and Troy
Audio Doctor NJ

Thanks, Dr.

My last email to KEF (the reference is to recordings I sent):


“Thanks.
Were you able to hear the sound?
Since my last email, I did substitute the new uni q you sent for the old one: the result is the same, if not slightly worse.
The effect is not limited to Mary Chaplin Carpenter, but (1) it is the worst found so far, and (2) I get identical results with the CD and a Bluesound Node 2 (same song, same places and times).
I’ve looked for sympathetic vibrations and discovered none. It is in both speakers, and clearly in the speakers, not a sympathetic source. By playing only one channel at a time, and standing directly in front of each, about a foot away, there is no mistaking it: it is a raspy, ripping sound, produced by each speaker, with the same music, in the same place or time, hence I must conclude it is either a design or fabrication defect in EITHER the uni Q or some OTHER component.
Believe me, I’ve tried what 50 years experience suggests and I can’t solve it.
Finally, to help others, be sure to inform them FIRST that there are TWO pairs of speaker connections, with Four connectors, not two. It helps to anticipate this on disassembly.
I must reserve all rights. I’m doing my best to mitigate but suggest there may be nothing more I can do.
By the way, my preamp is a Rotel RC 1590, and amp a Rotel RB 1590, connected with new Cardas XLR clear lights, and the speaker cables are new Transparent Plus. I got the same result in the left channel initially with a McIntosh c15 and mc202, with a Transparent music link, gen 1 speaker cable. I believe I overlooked testing the right side, but who knows....
I can’t justify throwing more money at better components when experience and reason strongly evidence a design or fabrication defect in some Component that makes up an R900 speaker unit.”

What at can I say, doc, I got burned. It certainly doesn’t make me feel better to state or imply the error in judgment was mine....😱

Of course, a component design defect would manifest in a similar manner, under similar circumstances, in all R900 speakers, though a fabrication defect would more likely be limited to contemporaneous components.