super tweeters

Has anyone here tried super tweeters - if so what were the results?

Nick.

 

Nick,

a good spread of opinion here....

20khz +

 

out of interest, where is it commonly assumed that human hearing tails off? (at the frequency extreme?)

enquiring minds with an eye for a mod or 2 want to know

 

16 khz?

 

in bubs case maybe 12khz

 

It's rather age/person dependent but this graph of equal loudness curves gives some idea (although not going right up to 20kHz I'm afraid):



Curves of equal loudness determined experimentally by Fletcher, H. and Munson, W.A. (1933) J.Acoust.Soc.Am. 6:59.

 

is it really 16khz?

that raises an interesting point (IMO)..

Tweeters that reach 16khz will surely begin falling off (when plotted on a graph) substantially before then.

I wonder if supertweeters 'bolster' the treble at these frequencies and make up for treble roll off ?

My horns are really a mid-range unit with some pretense at treble. They go to 16khz, but obviously fall off before then. You can hear a slight 'shut in' at the treble.

Its for that reason Ive been looking at a pair of JBL 2405's.

The normal dome tweeters I've seen usually quote treble frequencies up to about 22khz, but again Im sure they are rolling off well within human hearing.

Out of interest, how low (bass) does human hearing go?

 

Remember that the 20 khz bandwidth of human hearing is for a steady state sinewave. Due to the signal processing of the aggregate sensory information from many sensors that are diversified in both location (and hence time) and frequency response in the ear it is well accepted that the ears leading edge discrimination extends way above the corresponding steady state bandwidth. That is the best justification for super tweeters that I have heard.

It is also possible that super tweeters are better behaved at frequencies between 10 and 20 Khz also improving the sound quality even within the audible range.

Low bass is felt rather than heard. 16 hz maybe?

 

Did you spot the graph I posted above Chris? It's all a question of varying sensitivity rather than absolulte cut-off. You could I expect hear 10Hz if it was played loud enough!

 

The cut off might be very sharp below a certain point given the physical limitation of the cilia. To play loud enough would probably liquify your internal organs. You would feel it through your skeleton anyway. People have experimented with very long organ pipes. At least one died.

 

:yikes:

 

7 Hz is fatal, if loud enough.

 

back to the topic - these supertweeters shouldn't work but they seem to

sub woofers shouldn't have a midrange affect but they seem to

 

What does that particular frequency do to kill someone?

Genuine question, I have heard rumours about particular, err, reactions which can be set off in a person due to specific frequencies if loud enough (I believe 33Hz was one)....

 

I think it vibrates certain internal organs to bits.

 

Harmonics...

 

It resonates the internal chest cavity and standing waves destroy the internal organs.

Bass drivers effect on the midrange is well documented and backed up - no contention there as far as I am aware.

 

Hi,

The problem is that the human hearing is not a microphone.

The perception of a given steady state tone (the current measure of audibility in a physiological sense) is completely invalid as principle measure of audibility, EXCEPT for steady state tones.

The human auditory system is a mixture of a very unsophisticated and binary "bare" detection system (the ear - with 30+% THD @ 92db build in mechanically, using a very basic purely binary detection) with a purely "analogue computing" copmplex DSP system (parts of the brain) with a slow feedback loop (learning) build in.

To make predictions about what system 2 is capable of by evaluating system 1 is as accurate as comparing the military merit or not of a nuke vs. a crossbow on portability.....

Power to the Clandestine Insurgent Rebel Clown Army, for embodying the principle, while failing individally or corporatly to grasp it.

Ciao T

 

Yes indeedy. And all our standard analysis and signal processing techniques are based around linear fourier analysis. Modestly speaking, as someone who has worked in nonlinear systems theory and also neural processing algorithms the truth is very much more complex - but we reduce to the linear steady state solely for reasons of expediency based on tractability.

The sum of the whole is very much greater than the sum of the parts - given the extra processing done by the brain that utilises more available knowledge such as the pattern of spatial activation. An example being leading edge detection - a very useful evolutionary adaptation.

 

I thought human hearing was meant to extend to 20Khz unless you have damaged your hearing or old age is kicking in.

Having just tested that, I can definitely hear a pure 20KHz tone, 21KHz is too high though and I can't hear it. If I know when its kicking in I can juuuuust about make it out. My speakers are supposed to roll off at 22KHz though so maybe thats why I cant hear it. If it's not the speakers, I am surprised how quickly my hearing rolls off as I can hear a 19KHz tone REALLY clearly, 20KHz is clear if I am listening for it and 21KHz is in-audible.

I'm glad I tested my hearing actually because I went to a gig on Friday and my left ear was not working as well as it should for 2 days afterwards! My right ear was fine but I was sideways on to the speakers most of the gig. Quite worrying really, I think there should be more strict rules on how loud and the amount of distortion allowed at gigs and concerts. Its the distortion in the treble that gets me.