Tekton style like tweeter array good idea?

[Randolf]

There currently is some fuss about Tekton, especially since Erin (https://www.youtube.com/@ErinsAudioCorner) had reviewed a Tekton speaker and seemed to be forced to remove his review shorty after that. I very much hope that this matter will be resolved soon, since I very much appreciate Erin’s or Amir’s serious efforts in reviewing loudspeakers and other equipment. Free speech is essential for all of us, even if it might not be 100% correct sometimes. I was pretty surprised to hear that because to me Erin’s Tekton review sounded surprisingly good and I would say Tekton should be happy with it.

Anyway I would like to discuss one design principle that seems to be used in many Tekton speakers here:

Basically, most Tekton speakers have a rather traditional design with respect to treble and bass: One or two bass drivers in a ported cabinet and a single 1 inch dome tweeter are used. However, for the midrange they use an array of tweeter drivers identical to the one used for the treble. These additional “midrange tweeters” are attached via a bandpath filter in order to not interfere with the one “real tweeter”. Via this bandpath filter also more and more “midrange tweeters” are used towards lower frequencies. The idea seems to be to create a better midrange driver by utilizing the low mass diaphragm of multiple tweeter drivers. Of course, this approach has some problems that need to be addressed:

1. Low impedance due to many drivers operating in the midrange. This seem to be addressed by utilizing a combination series (might by problematic) and parallel connection of the drivers.
2. Operating the tweeters far outside of their usual frequency range (typicaly about 2-20 kHz) and even close (or perhaps below?) there resonance frequency (typically 500-1000 Hz). This may cause distortion, clipping, lower dynamic range or even desctruction of the drivers. I guesss Tekton tries to address this by just having to produce a lower SPL by each individual driver and using dome tweeters with low resonance frequency and an as wide as possible frequency range.

According to

Tekton use Scan Speak drivers (perhaps some OEM design?):

https://www.scan-speak.dk/product-categories/tweeter/
https://www.soundimports.eu/en/scan-speak-tweeters/

According to

they have a US patent https://patentimages.storage.googleapis.com/ef/3b/8b/91cfa120a70f05/US9247339.pdf on this sepcific way to arrange tweeter arrays. A crossover network sketch can be found here: https://www.diyaudio.com/community/threads/help-understanding-tekton-tweeter-array-schematic.336743/

Of course, using multiple (smaller) drivers is done since decades by many manufactures and DIYs. Typically, this is used for 2-4 bass or bass midrange drivers. Most of the time all drives share the same frequency range. Sometimes a second identical woofer is just added for the very low frequencies to extend the bass response. I had used this by myself with two KEF B110B in a ported cabinet 35 years ago (https://homeaudio.jimdofree.com/dirac-live/ picture at the very bottom). However, these approaches typically do not try to use drives for frequency range they are not intentionally designed for.

So is this a good idea? Is it cost effective or wouldn’t it be better to spent the money for a single high end midrange driver instead e.g. 6 additional tweeters? Are there any other manufactures or DIYs doing something similar?

Best regards
Randolf

 

[MZKM]

Is it cost effective or wouldn’t it be better to spent the money for a single high end midrange driver instead e.g. 6 additional tweeters?

Just to address this issue, if all the “midrange” tweeters are the same as the main tweeter, you can do a large bulk order and many places offers discounts on a sliding scale (10-100, 100-1000, 1000+).

 

[kemmler3D]

IMO this is an okay idea, not a great idea.

The idea that a lower moving mass has some inherent advantage in terms of "speed" is specious. If this could be demonstrated, it would be easy to demonstrate. Don't hold your breath waiting for the stunning results proving the merits of this idea.

I think it would depend on larger drivers having different frequency responses in the treble depending on what other frequencies are playing at the same time (this would show up in IMD/multitone plots if it was a problem), and/or static vs. dynamic friction coming into play, which is considered real but rare.

That said, you can do some interesting stuff in terms of SPL / distortion by dividing the load between many tweeters as Tekton does.

Unfortunately, from what I have seen in other threads, the effect of having many tweeters in a large area is not categorically different from having a large driver reproducing the same frequencies. In other words, you still get beaming.

So, it is a trade-off like any other when it comes to speaker design. By all accounts their speakers don't sound bad in practice, even though the measurements do show the beaming in the midrange. I think depending on your opinion the trade-offs might be worth it. So I guess it's not a terrible idea, nor does it clearly beat more conventional designs.

 

[YesChickenNuggets]

This guy talks like a moron. Those arrays are ugly as hell. They're aesthetically juvenile, absolutely revolting.

 

[dfuller]

I'd rather just use a decent 3" dome mid, though though the truly great ones seem to be as rare as hen's teeth for the DIY market.

 

[617]

I've simulated it and looked at measurements by people that have pursued it seriously. The Hannover hard-core guy has a great paper on it. Kemmler is correct, it is an interesting notion, and you can get it to sort of work, but it gets you nothing and creates a mess.

The distortion advantages are insignificant. You have lots of tweeters but the radiating area is smaller than a midrange. Many speakers use eight to fifteen inch woofers for kids and sound incredible. The directivity is narrow but inherently chaotic. If you wanted to do.it seriously you'd get tweeters with a smaller flange and pack them in tighter.

The difference in engineering knowhow between this and a competent coaxial is vast. This is a garage diy effort. If you want a dynamic coax get a big kef or me geithaine or genelec or even an old tannoy or altec.

The real magic of the tekton array isn't that it works well, it's that it manages to work good enough to not be considered broken, like many other conceptually satisfying but fundamentally flawed speakers such as panels or mangers or plasma tweeters. This differentiates the product and you get something that convinces consumers their judgement is special.

There are incredibly advanced speakers made by amateurs but this isn't it.

IMO this is an okay idea, not a great idea.

The idea that a lower moving mass has some inherent advantage in terms of "speed" is specious. If this could be demonstrated, it would be easy to demonstrate. Don't hold your breath waiting for the stunning results proving the merits of this idea.

I think it would depend on larger drivers having different frequency responses in the treble depending on what other frequencies are playing at the same time (this would show up in IMD/multitone plots if it was a problem), and/or static vs. dynamic friction coming into play, which is considered real but rare.

That said, you can do some interesting stuff in terms of SPL / distortion by dividing the load between many tweeters as Tekton does.

Unfortunately, from what I have seen in other threads, the effect of having many tweeters in a large area is not categorically different from having a large driver reproducing the same frequencies. In other words, you still get beaming.

So, it is a trade-off like any other when it comes to speaker design. By all accounts their speakers don't sound bad in practice, even though the measurements do show the beaming in the midrange. I think depending on your opinion the trade-offs might be worth it. So I guess it's not a terrible idea, nor does it clearly beat more conventional designs.

 

[dfuller]

So I just did some looking, for curiosity's sake.

A Bliesma M74S (74mm silk mid dome) has an Sd of 50.25cm². a T25S (25mm silk tweeter) has an Sd of 5.7cm².

You'd need about 9 1" domes to equal a 3" dome, and that would have worse distortion, worse LFX making the crossover more difficult, and the radiation pattern would be far less predictable.

IOW: solution in search of problem. There's a reason nobody does this.

 

[Duke]

Given suitable tweeters (which are available today) and crossover (which I haven't modelled), I can see Tekton's tweeter array resulting in a narrower-than-normal and more-uniform-than-normal radiation pattern over its frequency range. So, I see it as an alternative to using a horn to cover approximately the same frequency range, rather than being an alternative to a more conventional mid + tweet pairing.

This is the model which stands out to me as particularly elegant in concept, and especially for its price. I wish I could do a decent horn speaker in that size/performance ballpark for anywhere near that price.

 

[Keith_W]

The real magic of the tekton array isn't that it works well, it's that it manages to work good enough to not be considered broken, like many other conceptually satisfying but fundamentally flawed speakers such as panels or mangers or plasma tweeters.

I read this with interest. Would you be able to give a brief explanation as to why panels, mangers, and plasma tweeters are fundamentally flawed?

 

[kemmler3D]

I read this with interest. Would you be able to give a brief explanation as to why panels, mangers, and plasma tweeters are fundamentally flawed?

Panels: Beaming
Plasma tweeters: Ozone

Depending on your POV, maybe not fatal flaws.

Not sure about mangers?

 

[Doodski]

Panels: Beaming
Plasma tweeters: Ozone

Depending on your POV, maybe not fatal flaws.

Not sure about mangers?

I read some plasma tweeters use argon gas as part of the generation process.

 

[kemmler3D]

I read some plasma tweeters use argon gas as part of the generation process.

Cool, let me just get my argon tank out of storage then

I think there would still be a bit of ozone, because you can't keep the gases from mixing if the tweeter is open to the air, which of course it needs to be.

Plasma tweeters are an amazing concept but the practical reality is kinda rough.

 

[Blumlein 88]

I read some plasma tweeters use argon gas as part of the generation process.

The plasma gas is also to help keep the production of ozone in check. Nelson Pass made an ionizing plasma speaker and it put out tons of ozone as it was in the open air.

Ninja'd by kemmler3D

 

[Doodski]

Cool, let me just get my argon tank out of storage then

Between you and @sweetchaos I'm going to have a asthma attack from laughing too hard. Hehehe...

 

[Mnyb]

Perlisten use a 3 tweeter array packed tight in a single wave guide .

Tekton seems to have eyeballed the distance between the tweeters without actualy matching any dispersion pattern visavi the midrange/midbass drivers ?

Maybe it can be done better , but is the gains that great ? Get a coax driver, there are larger ones than genelec or kef uses if you want dynamic power . See sigbergs latest floorstander ?

 

[Mnyb]

But i dont design speakers so the finer details eludes me listen to the other guys here .

 

[Keith_W]

Panels: Beaming
Plasma tweeters: Ozone

Depending on your POV, maybe not fatal flaws.

Not sure about mangers?

Ozone is less of a problem if the plasma flame is small. This also means lower loudness and less LF extension, so a higher XO point is required. About the only problems I can think of is that (1) a plasma tweeter is inherently omnidirectional, so it needs some kind of horn or wave guide and then you have to deal with horn/waveguide problems, and (2) it eats electrodes. Don't ask me how I know. I would like to know if there are any other issues?

I don't think that beaming panels are that much of an issue, some people prefer beaming panels and some listening rooms may actually benefit from it. That is, unless the designer combined beaming tweeters with wide dispersion mids and the directivity suddenly changes. Are there any other issues with panels?

 

[voodooless]

The only way I see this properly working with decent directivity is in a 2d Bessel array. And even then, with tweeters that have an fs of around 500 Hz, you can’t exactly get very low, even if you have several them. The Moab BE array low crossover point is about 770 Hz (According to Stereophile). Definitely lower than one tweeter would go obviously. The 14 drivers of the Moab BE would be able to to do 117 dB max given 1mm xmax. Distortion wise it’s probably okay.


As for plasma tweeters and ozone: perfect for a smokers home: will get rid of the nasty smell

 

[ctrl]

This is the model which stands out to me as particularly elegant in concept, and especially for its price. I wish I could do a decent horn speaker in that size/performance ballpark for anywhere near that price.

The idea with the tweeter array is conceptually interesting, aside from the fact that the resonance frequency of the tweeter is hardly below 500Hz, so the lower midrange cannot be adequately served.

By dividing the tweeters into groups within the array, directivity can be fairly well controlled. If the tweeters indicated in blue receive a lower low-pass filter than the green tweeters, horizontal radiation can be effectively controlled.

For the driver indicated in red, used purely as a tweeter, I would experiment with a small, highly directional horns or ribbon horns. This would make the change in radiation less abrupt when transitioning to the actual tweeter. But maybe this abrupt transition is what is liked by the manufacturer and his customers.

Anyway I would like to discuss one design principle that seems to be used in many Tekton speakers here:

In the neighboring thread, I attempted a very simplified analysis of the concept with the double circular midrange array (direct link below) - used by Moab or Encore.

Tekton M-Lore Speaker Review

Sheesh, this is turning into a bigger clown show than needed. Apparently Mr. Alexander isn't fazed by loss of reputation or revenue. He strikes me as one of those grimey business owner's that only cares about profit more so than doing the right thing. Must've been that playground bully in his...

www.audiosciencereview.com

 

[voodooless]

horizontal radiation can be effectively controlled.

It's like a controlled crash landing. As you have shown, it's not a pretty picture