Supersonic

I have been wanting to play with some super tweeters ever since I saw the article on Paper & Oil a few years back. I probably won’t use them with my Shindo horns just due to the impedance matching fiasco that could ensue, but I do want to fiddle around with them on my Omegas, just to see what they do. I don’t actually miss any top end, but from past experience, and anecdotally, accentuating the high frequencies improves bass tightness, or at least the perception of it anyway.

Whilst I lusted after the Fostex T900A, my pockets are not that deep, so when a pair of T-90a super tweeters popped up I bid on them and managed to win. They were owned originally by a sadly passed audio acquaintance, so giving them another life and experimenting with them is hopefully something he would have wanted. They use alnico magnets which appeals as well.

I’ve ordered some enclosures and capacitors to make a nice simple crossover. I have some Fostex R-80B L-pad attenuators in my stash.

I am no expert when it comes to crossover design so I am going to stick with a very basic design like this one recommended in the Fostex manual:

I know there are millions of caps I could try, but I don’t want to invest megabucks into it, so I went for a 1.5uF Jantzen Superior Z-cap, which should be more than good enough for this purpose. I’ll use Belden 9497 for the cables since I have some in my collection of stuff.

I built the crossovers using some nice metal enclosures sourced from Aliexpress. I didn’t take an internal picture, but its pretty simple in there anyway.

I made up some lengths of Belden 9497 terminated with some Z-plugs soldered on with trusty Kester 44 solder. One end of the speaker cable is terminated with some spades I had.

I didn’t have enough spades to terminate the little jumper links between the crossover and tweeter, so I used some banana to spade adaptors I had, they work pretty well.

Spades piggy backed off the binding posts.

Initial listening definitely shows benefits. The Omegas sound much fuller now, a greater sense of scale and depth. Really nice extension in the top, and as expected the bass, or at least the midbass sounds tighter and deeper. The whole soundstage opened up and I thought there were improved timbral cues. A cool worthwhile experiment.