Hi KEF Speaker Owners,
Should you have a model of KEF speakers, or of any other brand, which was produced several years ago, and for which electrolytic capacitors were used in the passive crossovers? Actually, several manufacturers did that to reduce the production costs.
You would get an improvement just by having those caps replaced with polypropylene condensers. With time, electrolytic capacitors lose their original value and this, of course, affect the performance by changing filter frequencies and response curves.
I did proceed with such replacement on a pair of KEF floor standing speakers a couple of years ago for a friend of mine. There was an enormous difference. The sound was definitely more detailed and you would believe that they were entirely different speakers.
If you cannot do the capacitor substitution by yourself, it is worth getting the work done by a technician who knows how crossovers are build and preferably has access to the crossover schematics.
If some of you ever get the electrolytic capacitors replaced in their passive crossovers, please let me know your impressions about the improvements.