Which type of tweeter is the best, and why are there so many types of them?

[Plcamp]

A SB ADC in an elliptic waveguide and two 5" CAC.... could work.
According to Heissmann, an MTM with a small waveguide and two 5".... should give a pretty nice response:
https://heissmann-acoustics.de/en/dxt-wave/

I am not yet confident two 5” are going to work, because my application is open baffle, and I find it difficult to find drivers that can transition well from a pair of 15” woofers from 300 hz up to a waveguided tweeter. I suspect it will require back wings to work.
A coaxial compression driver in a biradial horn looks to be both the best (and most expensive) solution. The one I saw in Crowe’s horn was B&C non metal driver. I might get most of the benefit from a higher freq horn like his 600 hz version and simply extend one of the 15” bass drivers to cross into that.

 

[Digital_Thor]

I am not yet confident two 5” are going to work, because my application is open baffle, and I find it difficult to find drivers that can transition well from a pair of 15” woofers from 300 hz up

And this is why we have so many different drivers in general
Maybe this could be of some inspiration:
https://www.stereophile.com/floorloudspeakers/jamo_reference_r_907_loudspeaker/index.html

 

[Plcamp]

And this is why we have so many different drivers in general
Maybe this could be of some inspiration:
https://www.stereophile.com/floorloudspeakers/jamo_reference_r_907_loudspeaker/index.html

More after sensitivity in 93db or above…one 5” mid isn’t enough, two prob ok with 300 hz high pass and gives broad range for tweeter cross.
It’s same sort of thing for tweeter I think…needs to be waveguided to hit efficiency goals and allow lowest possible cross.

I am not sure what to think of differing dome materials. Since I can’t hear above 14k anyway, I expect in my case it’s more academic than impactful?

 

[Wes]

Is this meant to be ironic? To me "organic" is one of those mealy audiophile clichés that, to me, implies mellow but lacking in detail and dynamics.

it was a joke

For the record, tweeter diversity is a function of [1] the multi-factorial problems to be solved, and [2] marketing.

 

[Lavawood]

Don’t forget the plasma tweeter

 

[Freeway]

Don’t forget the plasma tweeter

Now that sounds like it might be 'organic'.

Is this meant to be ironic? To me "organic" is one of those mealy audiophile clichés that, to me, implies mellow but lacking in detail and dynamics.

I just don't get it. The use of the adjective 'organic' when applied to audio equipment. Of all the different subjective terms used to describe sound organic is the one that totally puzzles me and causes a WFT moment.

 

[mhardy6647]

it was a joke

For the record, tweeter diversity is a function of [1] the multi-factorial problems to be solved, and [2] marketing.

linear function?

Now that sounds like it might be 'organic'.

organic + plasma = ewww

 

[Wes]

linear function?

I never assume linearity, but a 1st order approximation can be useful. I have two stories:

At a seminar once time I was assailed for using a Taylor expansion, despite presenting a full sensitivity analysis showing that was of no consequence.

Earlier, as an undergrad. I needed to take an extra math course and saw one called "Linear Algebra" listed. "Hey it's linear, so it has to be easy!" I thought... While I survived being pierced by the sharp points of the eigenvectors, I learned that complex analysis was more fun.

 

[mhardy6647]

I never assume linearity, but a 1st order approximation can be useful. I have two stories:

At a seminar once time I was assailed for using a Taylor expansion, despite presenting a full sensitivity analysis showing that was of no consequence.

Earlier, as an undergrad. I needed to take an extra math course and saw one called "Linear Algebra" listed. "Hey it's linear, so it has to be easy!" I thought... While I survived being pierced by the sharp points of the eigenvectors, I learned that complex analysis was more fun.

I took linear algebra as an undergrad bio major -- my alma mater offered two flavors: the real lin alg and the other one. I took the other one, known far & wide as Linear Algebra for Poets.

I did think it was cool that one could use matrices to do regression analysis, though -- still do.

My favorite memory of that course: the professor, Dr. Schiffman, got a bee in his bonnet about something in the textbook and spent a whole class period bemoaning the fact that i was called an "imaginary number". Said he (in essence), "i is no more or less imaginary than any other number!" He felt really strongly that i gets a bad rap.

Did I mention that our son is a mathematician? He is endlessly amused whenever I try to do math in his presence. Fortunately, we're both pretty terrible at arithmetic.

 

[Timcognito]

I never assume linearity, but a 1st order approximation can be useful. I have two stories:

At a seminar once time I was assailed for using a Taylor expansion, despite presenting a full sensitivity analysis showing that was of no consequence.

Earlier, as an undergrad. I needed to take an extra math course and saw one called "Linear Algebra" listed. "Hey it's linear, so it has to be easy!" I thought... While I survived being pierced by the sharp points of the eigenvectors, I learned that complex analysis was more fun.

 

[Timcognito]

Sorry should have used a thumbnail

 

[mhardy6647]

Sorry should have used a thumbnail

nah. you're good.

 

[MaxBuck]

I took linear algebra as an undergrad bio major -- my alma mater offered two flavors: the real lin alg and the other one. I took the other one, known far & wide as Linear Algebra for Poets.

I did think it was cool that one could use matrices to do regression analysis, though -- still do.

My favorite memory of that course: the professor, Dr. Schiffman, got a bee in his bonnet about something in the textbook and spent a whole class period bemoaning the fact that i was called an "imaginary number". Said he (in essence), "i is no more or less imaginary than any other number!" He felt really strongly that i gets a bad rap.

Did I mention that our son is a mathematician? He is endlessly amused whenever I try to do math in his presence. Fortunately, we're both pretty terrible at arithmetic.

I realized quickly that EE wasn't for me when I was introduced to the imaginary cube roots of -1. There wasn't enough weed in the entire state of Indiana to let me wrap my brain around that.

 

[mhardy6647]

Not to dwell on the subject of Innumeracy* but, on the off chance I have never disclosed this here before.

I love the "hard" sciences. All of 'em. When I was matriculating into college, I looked carefully though the course catalog (remember those?) and discovered that Biology had the least requirements in terms of mathematics of any of the hard sciences at Hopkins (in those days) -- so, a Biology major I became. My PhD is also nominally in biology, although really biochemistry**.

I am actually not so much "bad" at math(s) as I am easily overwhelmed by math(s).
________________
*

** I used to say that I didn't know enough chemistry to be a chemist, nor enough biology to be a biologist -- which really used to tick my thesis advisor off.

 

[antennaguru]

I am partial to the JBL “Butt Cheeks” tweeter. Model 2404H Bi-Radial Horn, 100 X 100 degree coverage from 3 - 20 KHz, 105 dB sensitivity (1W/1m), 40 watts power handling, crossover at 3 KHz 12 dB per octave. These are pro sound tweeters used in the JBL Cabaret series, but equally at home in a medium to large room at home.

 

[Blumlein 88]

I know I'm just throwing a me too comment. I think electrostatic tweeters can be among the best. Have a couple of the beasties floating around here somewhere. And I do mean ESL tweeters, not the full range panels (as much as I love them). ESL tweeter really were never developed much for size and shape etc. as they could have been. Probably the need for high voltage just for the tweeter.

The tweeters that sound best to me, even better than ESL tweeters are ribbons. At least good ones. In terms of what I've heard they have had the finest sound for a tweeter. All there, extended, quick and yet not tizzy or over-hyped. Only in comparison to ESL tweeters do you hear the ribbons may be a tiniest touch slower than reality.

 

[mhardy6647]

I know I'm just throwing a me too comment. I think electrostatic tweeters can be among the best. Have a couple of the beasties floating around here somewhere. And I do mean ESL tweeters, not the full range panels (as much as I love them). ESL tweeter really were never developed much for size and shape etc. as they could have been. Probably the need for high voltage just for the tweeter.

The tweeters that sound best to me, even better than ESL tweeters are ribbons. At least good ones. In terms of what I've heard they have had the finest sound for a tweeter. All there, extended, quick and yet not tizzy or over-hyped. Only in comparison to ESL tweeters do you hear the ribbons may be a tiniest touch slower than reality.

Coupla pairs of these lurking around here in various dingy corners.

source: https://www.radioshackcatalogs.com/flipbook/1961_radioshack_catalog.html

DSC_0938 (3) by Mark Hardy, on Flickr
One of the four (?!) that are here may be seen (barely) to the right of the 515B woofer in one of the Frankenaltecs in the photo above. The R/S electrostatic is sitting under one of the (rather nice, actually) Radio Shack 40-1375 "leaf" (planar) tweeters, in a Hammond box enclosure with 1st order XO for "supertweeter" use. Note the blonde wood enclosure

I've never had sufficient gumption to see if any of them work -- much less the gumption of building their hyper-simple HV power supplies.
Early on, I think these were JansZen OEM, but most were built in Japan and may have little or any relationship to the JansZen electrostatic transducers of the early 1960s.

Low sensitivity of electrostatic drivers transducers is a disincentive for me, unfortunately. They are very smooth & sweet sounding, though.
The aforementioned 40-1375 is much more sensitive (low 90s dB SPL for 1 watt input @ 1 meter).

 

[mhardy6647]

Hmm... since this is a thread about "tweeter technology", and since @Blumlein 88 invoked ribbon drivers I feel the urge to say a little more (assuming I haven't already*) about the above-mentioned Radio Shack 40-1375 'planar tweeter'.

40-1375 by Mark Hardy, on Flickr

The 40-1375 was sold as a bare driver by R/S for quite a few years (mid-80s into the early 90s, give or take) as an add-on/supertweeter with claimed response to "50 kHz" The 91 dB (per watt @ 1 meter, presumably) sensitivity seems plausible based on my experience with these.

source: https://www.radioshackcatalogs.com/flipbook/1984_radioshack_catalog.html

1) This is not a true ribbon but rather a planar driver (not unlike the large planars used by Magnepan in the Magneplanar loudspeakers).
2) This driver was an homage to/ripoff of a then-popular driver made/sold by JVC. The 'real' JVC driver was much better built but I don't know if it worked or sounded any better than the R/S "version".
3) R/S also sold a complete loudspeaker system (the Optimus-400) that employed a more substantial variant of this driver. Perhaps (???) the Optimus-400 used the actual JVC OEM driver.

source: https://www.radioshackcatalogs.com/flipbook/1986_radioshack_catalog.html

I actually have a single example of the Optimus-400 tweeter here someplace -- pulled from a single dump-find Optimus-400! I couldn't rationalize rescuing the whole monkey coffin (not a single one, at any rate) but I was curious enough about the tweeter to salvage it. I don't think I've ever even determined whether it is in working condition or not.

_________________________
* I don't remember if I have already mentioned these drivers in this thread, and I am too lazy to check!

 

[hex168]

Back in the day, I used that JVC quite a bit as a cheaper alternative to the Panasonic EAS-TH400. The Panasonic was better; wish I could still get them. Here's a picture (not my ad):
https://techtalk.parts-express.com/...54871-fs-panasonic-leaf-tweeters-eas-10th400a

 

[MarkS]

the professor, Dr. Schiffman, got a bee in his bonnet about something in the textbook and spent a whole class period bemoaning the fact that i was called an "imaginary number". Said he (in essence), "i is no more or less imaginary than any other number!" He felt really strongly that i gets a bad rap.

That reminds me of this:

Pop science writer Isaac Asimov told a story he was proud of about his undergraduate days. A friend’s philosophy professor held court after class. One day he declared mathematicians were mystics, believing in things they even admit are “imaginary numbers”. Young Asimov, taking offense, offered to prove the reality of the square root of minus one, if the professor gave him one-half pieces of chalk. The professor snapped a piece of chalk in half and gave one piece to him. Asimov said this is one piece of chalk. The professor answered it was half the length of a piece of chalk and Asimov said that’s not what he asked for. Even if we accept “half the length” is okay, how do we know this isn’t 48 percent the length of a standard piece of chalk? If the professor was that bad on “one-half” how could he have opinions on “imaginary numbers”?

https://nebusresearch.wordpress.com/2020/08/13/my-all-2020-mathematics-a-to-z-imaginary-numbers/

I realized quickly that EE wasn't for me when I was introduced to the imaginary cube roots of -1. There wasn't enough weed in the entire state of Indiana to let me wrap my brain around that.