I have been considering hopefully improving the sound of my lovely Impulse H2 speakers. Initially I thought I would replace the capacitors in them as they are probably getting a bit old in the tooth by now. H2 builds varied quite a bit over the years I believe, mainly the siting of the crossover. Mine has the crossover on the inside mounted on a board that is secured to the rear of the cabinet by 6 screws, on the outside of this board is where the 6 speaker posts are. It is quite straight forward to get the board off but with limited movement due to the length of the internal leads to the speakers.
I removed and have examined the crossover circuit which looks quite straight forward, two large capacitors and one smaller one, all are black and I think oil filled ones but I could be wrong, by the way I have limited electronics knowledge. I examined the capacitors carefully looking for markings to indicate what voltage and microfarads they are rated as with a view to ordering high quality replacements. Unfortunately they seem to be completely unmarked .
I have searched the internet for crossover wiring diagrams for the H2's but can find none, I did find some pictures of a redesigned crossover for an upgraded pair and also a pair of Taus (the last version of H2's that look slightly different). But in both cases the circuits look a bit different, probably I believe due to the tweeters being replaced and I suspect an upgrade to improve the top/mid range crossover point.
If anyone has any info or could guide me in the right direction it would be appreciated. I was hoping to do the simple capacitor swap myself, and then to look at making a minor mod to the circuit to improve a 450hz dB drop (I believe this is a standard tweak).