Super Tweeters

Hi fellows. Has anyone ever try out the super tweeters from either Townshend, Tannoy or Elac?
If you have, did they provide any improvement?

Thanks

Elac, wired in parallel with some 5-digit Eurodollar top gun speaker.

It totally messed up the upper freq response as it was wrecking havoc on the load impedances and the poor amp was totally confused on how to drive the upper freqs.

Be very careful of aftermarket add-on super tweeters. They can do more harm than good.

Similar situation to simply adding a sub to try and bolster the bass from a pair of stereo speakers but ended up causing a bigger mess instead.

The constraining factor of linking an external super tweeters to a pair of speakers is the miss-match of sensitivity. The super tweeters generally have a sensitivity higher (say 110db/m) than most speakers (say 90db/m).

Basically the miss-match of 20db/b sensitivity can be corrected using an L-pad attenuator or resistors network. Otherwise, the super-tweeter would dominate the upper frequencies and sound very bright.

The other issue is the crossover point for the super tweeters with the speakers. Having the response curve of the speakers would be useful in having a super tweeter to "reinforce" just the upper registers.

Have fun with the experimentation.

No one can guarantee that the supertweeters' (ST) output would re-inforce the main speakers' HF output, or actually cause out-of-phase effects, because no one really know whats the phasic response of these afterthought supertweeters against the main loudspeaker's curves.

While a ST may output a fair bit of treble energy, its highly unlikely it would be phase-coherent with the main speakers' tweeters. So it just ends up becoming a total Magnum-4D scenario whether it might work well in the existing setup or not.

From real-world experiences:
When i measured the room response with the Elac SuperTweets in parallel to the main speakers, there was actually a decrease in midband output by a few dB, suspected to be a more demanding load on the Amp which probably saw the mid to HF load as having lower impedances and hence struggled to deliver the required amplification. The ST caused a mid-HF section suckout effect.

If i can dig out the Audio plots somewhere in the HDD (if I still have them saved), i'll post them up here...


Red trace was the normal room response.
Blue trace is with the Elac supertweeters attached.


Note the dip from 1KHz onwards with the Supertweet attached and it's overall midband loss until about close to 18KHz (view the image in a separate browser window to see the full graph in case its truncated here in this message board) when it gains approx 6dB close to 20KHz before falling off even faster.