What is the ideal High Freq extension?

Detlof,

Sure I would certainly be interested to know the your acaoell tweeter experiment. How did you measure your Sound lab extension to 20K hz? Via Sound meter? with necessary correction applied? ( Here in US we have Radioshack sound meter that I typically use).

CKoffend, thanks for reminding me that live music extends well past 20 Khz (How can i forget? with recent threads comparing analog vs digital medium) as much as like 70k hz and beyond for certain instruments.

So in a perfect system you would want 'flat' response to and beyond 20khz- No roll off. Hmmm Now It makes sense why some audiophiles(Detlof and some other I know)prefer super tweeters hooked up to their main speakers.

Now that I think and look back I do remember auditioning a super tweeters in an all audio note system and discerning difference between these tweeters being on and off!

Any recommendation which super tweeters to try with my Dunlavy Vs?

It depends on how old you are and how good your hearing is. When I was in my late teens, I could hear up to 18Khz. Now, 30 some years later, I could hear no more than maybe 12 or 13Khz and music sounded very different to me than when I was much younger.

I have heard speakers with purposed response to 50Khz.While you might not hear that high up,the over-tone structure may be more completely revealed.A lot has to do with the crossover and phase linearity.
You must remember when digital "brick-walled" everything above 20Khz.Thank goodness we got past that!

Nil, I borrowed a hand held spectral analyser with a microphone built in its "nose" cum pink noise generator in a wall wart type of thing. Can't remember the name of it, but it was US-made, if I recall right, had a lot of LEDs in its display. A nifty little thing.

I think spectral analyzer would be more accurate way to measure system system response at your listening position. I think the Ratshake sound meter may not be accurate the freq extremes even with so called corrections applied.

I measured my system response at about 7 ft away (my seating position) and it is RULAR flat ( with corrections applied) from 25 hz to 16 khz. with 2 db boost at 20 hz and 7 db down at 20 kHZ.