Tekton style like tweeter array good idea?

[CleanSound]

Not clear on your point here. But I asked about the tie to Monitor Audio. All good as just figured you had made a typo (66 vs 67).

And now I believe we are in sync.

One thing to note, I never believed anything about Tekton because I watched some of Eric Alexander's videos when I first learn of his company and those videos was all technobabble. Which led me to read up on one of his patent, and I can confirm it is absolutely nonsense, all of this is several years ago. I have never believed there are any real science and merit from EA and his company, I don't now and after the recent debacle, I never will.

 

[cavedriver]

Thanks, found the reference in Post #67 (not 66). Agree, would not even loosely equate Monitor's custom driver array with Tekton's.

Agreed that the Hyphn is probably better. In contrast to Andrew's quoted comment above, Monitor (and McIntosh) is using a cluster of custom 2" drivers, not off the shelf 1" tweeters like Tekton. When you play with the diameter like this then you can get close to the Sd of a small midrange (6 x ~25 cm2 = 150 cm2 vs 133 cm2 for the Purifi PTT6.5M04-NFA-01 6.5" midrange). Also, since they are custom you can engineer them with much lower Fs (and potentially higher Xmax). The Hyphn crosses over to the woofers at a reasonably low 350 Hz, much lower than what Tekton can do.

The part I can't tell without more audio engineering understanding and measurements is how well does Monitor's claim that, "the smaller the radiating area of the drive unit, the wider the directivity for the best in-room integration" work. Their design, as I noted above, has the radiating area of roughly a 7" midrange, making it a fairly large total radiating area. With the drivers spaced out around the tweeter the outer edge of the virtual circle is more like the edge of a 9" cone. Monitor's high cross for this is 3700 Hz. Depending on how driver arrays like this really work compared to a single cone it might seem that there would be significant beaming or poor off-axis response given that a 7~9" cone driver would beam significantly by 3700 Hz, although if you could make something like a 7" BMR driver with it's flat radiating surface, might it not behave much better up to those frequencies?

 

[Multicore]

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.

I suspect that some people like beaming as it can introduce perceptual effects that give an impression of "soundstage". Arrays do more than form beams though (don't they?) like complex frequency dependent radiation patterns. And again I suspect some people enjoy that. I'm sure lots of us have had the embarrassing experience (I'm not asking anyone to admit anything) of wiring up a new system and saying something to the effect of: "That sounds interesting. Yes." Even if only to said to yourself for a moment but quite possibly for much longer before twigging to the polarity wiring error.

Or to put it another way, if you just dropped a tonne of dough on new kit and are looking forwards to "great sound" once you're done setting it up, neutrality is pretty boring.

 

[ctrl]

On Erin's Facebook group, Andrew Jones commented on the validity of using an array of tweeter sized drivers for mid-range and he personally does not believe it makes sense base on the surface area.

... the statement is IMHO not quite right.

Sd for a 1'' tweeter is usually between 6-10cm². With six units, you would therefore have a summed dome area of approximately 36-60cm² - for example, 1'' tweeters from SBAcoustic and Seas.

The tweeters in the "circular midrange array" are, at least as it seems, used by Tekton as pure midrange drivers. Therefore, the crossover frequency, solely due to the high-pass behavior of the tweeter below fs (tweeter resonance frequency), should be significantly above 500Hz (actually above the fs of the tweeter, but that's another story).
So, when using six tweeters (with at least an electrical first-order high-pass filter, meaning one capacitor), the low excursion of each individual tweeter of +-0.2-0.5mm should not be a real problem.

So, one should now compare the array with "real" midrange drivers. Therefore, let's look at 4'' drivers that are usually (when used solely as midrange drivers) used from 400Hz onwards.
Their cone/dome area is around 50-60cm². For example, an old-school paper cone midrange driver from Monacor or a midrange dome driver from Bliesma.

One could argue that one would want to avoid resonances as much as possible. However, the larger the cone/dome area, the lower the frequencies at which eigenmodes or even break-up modes occur. As a result, the driver no longer exhibits piston-like behavior, and each resonance requires time to decay. Whether this is audible is not initially relevant in "high-end" audio (some audiophiles especially like silk domes and there you have "controlled" resonances all over the place).

A tweeter used above its resonance frequency exhibits this behavior only very late and shows piston-like behavior up to high frequencies (aside from the first possible surround resonance and except for silk dome and typical paper cone tweeters).

The logically more sensible approach would have been to investigate which midrange drivers still exhibit piston-like behavior up to the desired crossover frequency, and to build the circular midrange array from these, probably 2''-3'' midrange drivers.
This way one would have overall 90-150cm² cone area and a piston-like behavior like tweeter will have and one still could control directivity of the midrange array by grouping the drivers.

 

[RickS]

Agreed that the Hyphn is probably better. In contrast to Andrew's quoted comment above, Monitor (and McIntosh) is using a cluster of custom 2" drivers, not off the shelf 1" tweeters like Tekton. When you play with the diameter like this then you can get close to the Sd of a small midrange (6 x ~25 cm2 = 150 cm2 vs 133 cm2 for the Purifi PTT6.5M04-NFA-01 6.5" midrange). Also, since they are custom you can engineering them with much lower Fs (and potentially higher Xmax). The Hyphn crosses over to the woofers at a reasonably low 350 Hz, much lower than what Tekton can do.

The part I can't tell without more audio engineering understanding and measurements is how well does Monitor's claim that, "the smaller the radiating area of the drive unit, the wider the directivity for the best in-room integration" works. Their design, as I noted above, has the radiating area of roughly a 7" midrange, making it a fairly large total radiating area. With the drivers spaced out around the tweeter the outer edge of the virtual circle is more like the edge of a 9" cone. Monitor's high cross for this is 3700 Hz. Depending on how driver arrays like this really work compared to a single cone it might seem that there would be significant beaming or poor off-axis response given that a 7~9" cone driver would beam significantly by 3700 Hz, although if you could make something like a 7" BMR driver with it's flat radiating surface, might it not behave much better up to those frequencies?

You are right in that there is more than just radiating area to consider. Some of the issues could be solved with different drivers, spacing and active filtering. The Monitor Audio implementation indicates their could be potential. If Tekton was attempting to create a midrange array, we can see numerous shortcomings with the design. For me comparing the Tekton array to the MA one is like comparing a cheap coaxial to a KEF coaxial. Sure they both have 2 drivers and the same shape, but the KEF actually performs well.

See @ctrl chimed in and he has a better handle on the acoustical aspect.

I need to bow out for a bit and wrap up my taxes!

p.s. one major electrical challenge in multiple driver array is keep the impedance reasonable. Ofc, with a custom driver you have much better control over the impedance. For Tekton to do with a 4 ohm tweeter suggests that some of the inductors used likely cause some additional output attenuation.

 

[1st.Virtual.Me]

Patents aren't proof.
And I don't think any independent reviewers will bother to measure this brand anytime soon.
IMHO: I don't see any clear advantage to such an array as this.

 

[dasdoing]

some people like beaming

I love beaming. I am imagining here a giant ring array of tweeters big enough to reproduce everything above 100Hz (coupled with a sub or 2) and starting to beam as soon as 200Hz lol

 

[Minoes]

I generally find quasi-coaxial louspeakers interesting and there have been some attempts in the german DIY scene to implement such arrays with very small widerband drivers:

Monacor Raduno
View attachment 362625

Monacor Raduno

Das „Andere“ zu bauen, das, welches es im Laden einfach nicht gibt, ist einer der größten Spaßfaktoren am Selbstbau. Und den meisten Spaß macht‘s, wenn selbiges dann noch so exzellente Ergebnisse liefert wie der clevere Mittelton-Revolver von Monacors Raduno

www.hifitest.de

Franks Circular Array
View attachment 362627

FoLLgoTTs Quasikoax 1
View attachment 362628

http://loudspeaker-research.de/

Hi, I'm very new to this forum but this kinda caught my attention, I'm actually playing around with something like this with 6 2 inch tectonic BMR's and a tweeter in a 3d printed "Baffle"

 

[Salt]

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?

Catching up here and just picking up Manger: any measurements of driver or speaker using it available (mine are 30 years old or so)?
Following the theory the sound producing diameter should reduce by rising frequency, so 'adaptive' directivity is provided.
Any data?

 

[Timcognito]

Catching up here and just picking up Manger: any measurements of driver or speaker using it available (mine are 30 years old or so)?
Following the theory the sound producing diameter should reduce by rising frequency, so 'adaptive' directivity is provided.
Any data?

A good number of posts over at diyaudio.com if search the manger.

 

[dfuller]

Sd for a 1'' tweeter is usually between 6-10cm²

It's closer to 5-7 usually, from what I can see. Regardless... you're still looking at ~7-10 drivers for an equivalent radiating area as a relatively small midrange, and that just doesn't make sense to me, it doesn't really have any benefits vs a more conventional design.

One could argue that one would want to avoid resonances as much as possible. However, the larger the cone/dome area, the lower the frequencies at which eigenmodes or even break-up modes occur. As a result, the driver no longer exhibits piston-like behavior, and each resonance requires time to decay. Whether this is audible is not initially relevant in "high-end" audio (some audiophiles especially like silk domes and there you have "controlled" resonances all over the place).

Part of the advantage of the big domes is their radiating area is quite high for their diameter, but the breakup modes are still usually way outside the passband - even for a fabric dome, we're talking ~4.5k or so which is well above where you'd start rolling it off with a typical tweeter.

 

[Randolf]

Hi, I'm very new to this forum but this kinda caught my attention, I'm actually playing around with something like this with 6 2 inch tectonic BMR's and a tweeter in a 3d printed "Baffle"

Thanks for pointing out the Monacor Raduno DIY Kit tested in german Klang+Ton 1/2011 magazine (https://hifitest.de/shop/de/klang-ton/245-klang-und-ton-1-2011-epaper.html). Since I frequently read Klang+Ton I checked out the data. It is a 4 way partially active design utilizing:

3x Monacor SPH-8M woofer
6x Monacor SPX-20M midrange 2" inverted dome
1x Carpower DT-284S tweeter dome

Crossover points: below 100Hz, 290Hz, 3kHz

The 6 midrange drives are attached by parallel wiring the 2 sets of 3 drives wired in series. The crossover network is pretty complex (especially for the tweeter since the closely located midrange drivers cause some trouble) and in addition a Monacor SAM-2 active modul is used.

The midrange and tweeter drivers are aranged on 10mm MDF handmade ring. So again it is a combination of multiple midrange drivers around a single tweeter.

Published Frequency response:

 

[gnarly]

Some of the issues could be solved with different drivers, spacing and active filtering

Yep, I'm sure they could be improved on...and do doubt with some issues solved..

The thing I can't see getting around, is simply how to get drivers to tight pack together so 1/4WL coupling occurs, through the freq spectrum.
Best illustration of that l goal I've seen is this...snipped from a TDanley patent.

I think it would take this kind of mess, along with the perfectly right drivers for each ring...not to mention correct spot-on xovers and processing.
Did I say before, just say NO to ring radiators ...lol

 

[Head_Unit]

So is this a good idea?...Are there any other manufactures or DIYs doing something similar?

It's an idea, and not a new one.* As I just posted in another thread, arrays of tweeter and even midranges are nothing new at all. Maybe nobody has done the giant one with a tweeter in between clusters of more tweeters above and below. To your "cost effectiveness" question I would *think* a good horn would be superior however it will surely sound different.

The thing about loudspeakers that I've learned over a couple decades of design work is that
- They are all quite inaccurate especially compared to electronics
- So every speaker, great or even "crappy" will emphasize something that pops out at you. Therefore most any design will sound good on some music.

 

[ctrl]

It's closer to 5-7 usually, from what I can see. Regardless... you're still looking at ~7-10 drivers for an equivalent radiating area as a relatively small midrange

Tekton uses SBAcoustic dome tweeter which provides several different tweeter with 10cm² Sd - see the link in the previous post or here and here.
In the Tekton speaker models with "circular arrays" are 6-14 tweeter used. So dome area isn't a real problem as long as the crossover frequency is chosen sensibly.

Part of the advantage of the big domes is their radiating area is quite high for their diameter, but the breakup modes are still usually way outside the passband - even for a fabric dome, we're talking ~4.5k or so which is well above where you'd start rolling it off with a typical tweeter.

I agree with your statement for stiff materials like Al or Be domes, sorry but for slik domes it might be wrong. Easy to show, using the measurements of the Bliesma midrange drivers (identical except for dome material):

Source: HifiCompass

The Al and Be midrange domes run practically parallel to each other up to 6kHz, the difference in SPL is due to different dome weights.
The silk dome is completely different, above 2kHz there is probably no more piston-like behavior.

As mentioned in the post you quoted, there is another resonance in the usable range of the midrange domes (and even more so of all midrange woofers) - all kinds of surround resonances.
Of course the Bliesma midrange drivers are SOTA, but even there you can see the fundamental resonance (half-wave)*** at 700Hz and the multiple at 1.4kHz in the diagram.

Don't get me wrong, I don't say that this is clearly audible, but one can find arguments for the use of a midrange array with 2-2.5'' midrange driver.


*** midrange driver Sd is 50cm², so radius is about 4cm and thus the circumference at 25cm. This means that the half-wave for the first surround resonance is around 700Hz.

 

[CinamonRolls]

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.

Will you please explain why it would be difficult with a horn. Curious to know where the project would run into constraints. Also wondering what advantages this has over the horn.

Thanks

 

[Duke]

.

Will you please explain why it would be difficult with a horn. Curious to know where the project would run into constraints.

Production cost is the hurdle that keeps me from building what I would consider to be a decent horn speaker in the same size/performance/price category as the Tekton "Perfect Set" speaker that I linked to.

This is the closest I ever came, fourteen years ago, and it was almost a thousand dollars/pair more expensive even then:

The Rhythm Prisms

The Rhythm Prisms

www.audiocircle.com

Also wondering what advantages this has over the horn.

Without knowing enough specifics of how the circular tweeter array performs, I couldn't reliably compare it with a good horn.

 

[Penelinfi]

Maybe you could use one of the many faceplateless tweeters or 1-1.5" full range drivers around?

 

[CinamonRolls]

Production cost is the hurdle that keeps me from building what I would consider to be a decent horn speaker in the same size/performance/price category as the Tekton "Perfect Set" speaker that I linked to.

This is the closest I ever came, fourteen years ago, and it was almost a thousand dollars/pair more expensive even then:

The Rhythm Prisms

The Rhythm Prisms

www.audiocircle.com

Without knowing enough specifics of how the circular tweeter array performs, I couldn't reliably compare it with a good horn.

In that thread you said, "One application I want to explore is home theater without a center channel. I think the RPs would work quite well in phantom center mode, which might be quite attractive if one isn't using a screen that the center channel can be hidden behind."

Did you ever explore that and how successful do you think it was?

 

[Duke]

In that thread you said, "One application I want to explore is home theater without a center channel. I think the RPs would work quite well in phantom center mode, which might be quite attractive if one isn't using a screen that the center channel can be hidden behind."

Did you ever explore that and how successful do you think it was?

Imo it usually works and works well for most people even from well-off-centerline seats. But if someone has a significant hearing imbalance (one ear hears significantly better than the other), then having a dedicated center-channel speaker would usually be better.

Imo there are two worthwhile advantages to using two controlled-pattern speakers in phantom center mode set up for time/intensity trading: No potential timbral discrepancy due to a different-sounding center channel speaker; and, greater soundstage depth than with a dedicated center channel. Admittedly these two attributes would matter far more for music videos than for movies, where one would probably not be noticing such things.

I had at least two customers sell their fairly expensive center channel speakers because they preferred not to use them. One of them recently me told me he had a friend over to watch a movie on his home theater system. The friend works for a company associated with the home audio industry but I didn't catch the company's name. Anyway they watched whatever movie, and when it was over my customer activated the motor to retract the ceiling-mounted screen. As the screen was retracting higher and higher his friend was bug-eyed searching the now-exposed wall in a moment of cognitive dissonance: There was NO center channel speaker hidden behind the screen, which was NOT what he expected!

Here's a photo, the speakers are actually a follow-on to the Rhythm Prism but the basic idea is the same (same drivers, bigger and nicer box, plus a rear-firing tweeter):