View Full Version : Attention all Impulse Loudspeaker owners!

08-12-2014, 21:20
RFC is delighted to announce a new service for the upgrading/repair of all impulse H6/Lali loudspeakers. I may extend this to others in the range at a later date.

Basically, there were several issues with these speakers, namely that after some years, there have been lots of reports of failing tweeters. RFC has looked into the failure modes for the t90K and T120K tweeters (no longer made or available) and the failures have all been due to two main ussues:

1. De-lamination of glued joints between voice coil formers and the inverted Kevlar diaphragm;
2. Wear/failure of the surrounds.

In either case, repair may be possible BUT any attempt at re gluing the formers will affect diaphragm inertial characteristics and hence frequency response and distortion. For all intents and purposes, the tweeters are not repairable which is a shame.

I have the solution though. RFC has designed and manufactured one piece CNC machined plugs which fill the existing tweeter opening gap and these plugs are cut for new SEAS tweeters (27TFFC) which are a superb replacement for the originals.

We also re-engineer the crossovers for better phase matching and convert them to 2nd order from 1st order which lowers distortion plus take the crossovers external as an option. The existing crossovers varied (some were 1st order whilst later ones seemed to use a combination of 2nd order bass/first order tweeter) and were engineered without really getting the best from the drivers possibly due to cost constraints.

The result of the RFC upgrades is a speaker good for another several decades, with a higher quality crossover and better off axis performance/lower distortion.

please PM me for further details or use the RFC website contact page to contact me.