Thoughts on adding a Super tweeter .

I auditioned a super tweeter...non ribbon variety...that went out to 50khz, I believe. It added a subtle bit of air and openess to the presentation. Super tweeters reproduce frequencies that are beyond what humans recognize as treble energy.

The effect of the super tweeter was subtle. I decided it wasn't worth the $1000, but we all put different price tags on these things.

I agree with the Tennis man on the overabundance of upper mid / lower treble energy. I base this assertion on my experience at CES / THE this year. Room after room had this characteristic. Even my own system has it to a degree, which annoyed me until I came home from CES. Then I turned on my system and it was a relief, because many (most?) of the rooms at the show had it far worse than my system does.

Also, keep in mind that a CD can not reproduce sounds above 20KHz. While it may theoretically be capable of producing "perfect sound" below this frequency, it has never been billed as having any capability above that point. So what you will be reproducing from a CD is not the musical content,but the residual digital noise that doesn't get filtered out by the player's filters. The better your player, the less of this there should be. Maybe if you're playing analog, there would be some content from the original event buried in the grooves.

Also, keep in mind that a CD can not reproduce sounds above 20KHz. While it may theoretically be capable of producing "perfect sound" below this frequency, it has never been billed as having any capability above that point.
Honest1 (Threads | Answers)

That's true for redbook CD, but SACD and DVD-A reproduce sound up to 100khz.

I heard a super tweeter on a neighbor's SET system. Although there was
noticeable HF extension over his single driver speakers, the superimposed
lower HF brought on a heightened upward tilt that I didn't care for.

My experience is a bit different than most of what has been reported here.

I am definitely not an insect: my hearing dies well short of 15kHz, however the addition of the Townsend supertweeters to my Quads was a revelation: the entire sound stage became better developed (source is vinyl). I did not hear increased upper frequency 'hash': in fact the upper midrange is where I heard the most dramatic improvements (perceived improved clarity, lucidity). The overall effect: 'it sounds more real'.

I don't really 'hear' the supertweeters when listening, but it is quite noticable if you take them away. My non-audiophile wife was listening with me and clearly heard the difference when the tweets where taken out and put back into my system. I have also heard from other quad owners that the Townsend's enhanced their systems in a similar manner. The Quads do not have 'dc to light' frequency response so YMMV.

The addition of the supertweets is somewhat akin to the addition of a good, well integrated subwoofer; with a 'woof it's not merely the lower frequencies that are audibly improved, the upper frequency ranges also benefit.

I think this is one of those 'listen for yourself in your own system' situations. Supertweets cannot be dismissed as 'crackpot audiophile psuedoscience'. They can make an audible improvment in a high resolution audio system.