Why are single drivers disliked to such an extent by most in this forum?

[IPunchCholla]

not always, for example you can't convincingly emulate different placement of a speaker, quite a lot engineers use single auratone speaker to have a reference of a real mono single source in the middle, not just phantom one. You can't emulate closed box design with bass reflex one, you can't emulate different beam width, you can't make nearfield coaxial monitors sound like a floor standing domestic speakers further away and it's not even a matter of one being better than the other, just different. As far as I know ARC3 only emulates the EQ curves of different speakers, so no nonlinearities are being added, which could be useful if you want to test for example to what extent a low bass would physically excite or distort a small speaker in a given mix.
However it works for some people, for example there's a system controlled by a remote in all Barefoot monitors which changes the overall sound of them to emulate same stuff. I didn't like it when I tried them, as it seemed like just an EQ curve, but it could be usable. Some engineers like Shawn Everett use a multiband compressor plugin just to solo certain bands, it's like soloing subwoofer or a tweeter, to hear what's going on in very specific frequency area but without distractions from the rest of the spectrum.
What I like about referencing is to change the environment all together. So I like to hear mixes in my car because it's boomy (100Hz and around is crucial to get right with it), with road noises drowning the details (so I can hear what's really sticking out), and with skewed stereo field. Or when I'm at home with my laptop, so no bass at all and very close to my face, this also shows a completely different perspective and it's impossible to emulate with software and speakers further away. I have a friend who uses a boombox that sits below the desk and it's playing the other side of the room, he likes to check mixes on it to hear if anything is sticking out, in a way like a passive listener would with music playing in the background.

Thank you! Very insightful.

 

[computer-audiophile]

To mention here one more exotic, which is not a really useful solo full range driver imo, but still covers a really extreme frequency range from about 80 Hz to 40 kHz, that is the Manger transducer. In a studio of the University of Music Karlsruhe I could hear one example once in an auditorium. They use it as monitors hanging from the ceiling. Here it is combined with a bass driver. (My photo is showing one of these monitors) But I can't judge it after this short single experience.

Manger® Sound Transducer — Manger

Manger Audio - Precision in Sound - Thrilling audiophiles worldwide since 45 years with the patented breakthrough technology of the Manger Sound Transducer

mangeraudio.com

 

[Down South]

If you mean the Transar, it was a two-way dipole.

I've actually got a pair of the 'grand heils' and as in the photo it's best to use them outside of any enclosure. I could never seem to find the right woofer to use them with.

 

[computer-audiophile]

For some people, the old ways are still the best ways.

Jim

I think that's what you call a weak argument. In German I would call it a 'Totschlagargument', but I don't know a good translation for it.

 

[tuga]

For some people, the old ways are still the best ways.

Jim

I think that only a tiny minority is actually supportive of single-driver speakers.
Some will build a pair because it's easy, several will buy a pair because of the hype, they're interested in S.E.T. amplification or just for educational purposes.
Ultimately most will recognise the shortcomings and move on to multi-way speakers.

 

[Keith_W]

I think that's what you call a weak argument. In German I would call it a 'Totschlagargument', but I don't know a good translation for it.

According to Google translate, "tot" = "dead, "schlag" = blow. And "Totschlagargument" = "killer argument". In English a "killer argument" is an argument that kills all other arguments, because it is so effective and irrefutable. In German it means the opposite?

 

[computer-audiophile]

In German it means the opposite?

A Totschlagargument is often used to end a discussion or silence the opponent, even though it lacks real substance.
It aims to dominate the discussion without addressing the actual facts or reason and doesn't convince in a logical or persuasive manner but rather relies on manipulation.

 

[Keith_W]

A Totschlagargument is often used to end a discussion or silence the opponent, even though it lacks real substance.
It aims to dominate the discussion without addressing the actual facts or reason and doesn't convince in a logical or persuasive manner but rather relies on manipulation.

I see. You are right, there is no English translation.

 

[computer-audiophile]

Have I mentioned the Ohm-F in this thread before? It just came to mind. Thinking about it for a long time, I can think of more and more fascinating designs of true full-range single driver speakers that have accompanied me on my audio journey.

The old Ohm F was a speaker that could really rock, with a massive bass tone. However, it required a lot of power, preferably around 1000W, which few amplifiers could deliver in its day. I still have fond memories of it.

Image from the internet:

 

[NTK]

It seems I need education. May I ask you to post some links to help me?

I am not too familiar with this technology myself. You can look up Google scholar on bending wave loudspeakers and distributed mode loudspeakers, the technology the Tectonic BMRs are based on.

It also happens that I have a side project to understand and follow the work of Ronald Aarts and Augustus Janssen on modeling a loudspeaker as a flexible spherical cap radiator. They gave the mathematical formulas to simulate the sound radiation of an axisymmetric flexing membrane, which, I believe, can model the operation of the BMR pretty well.

Aarts and Janssen use the radial part of the Zernike polynomials to model the axisymmetric deflections of circular membranes. Below are some illustrations -- the graph below is the first 5. You can see from the Wikipedia page that only the R_2n^0(ρ) polynomials are even (R(ρ) = R(-ρ), and therefore axisymmetric).

Zernike polynomials - Wikipedia

en.wikipedia.org

R_0^0(ρ) = 1 represents the rigid pistonic mode. The other modes give different diaphragm bending shapes in increasing complexity as n increases.

Below are the simulated polar radiation maps of diaphragms oscillating with these deflection shapes using the formulas given by Aarts and Janssen, normalized such that the on-axis maximum response at 1 m is 40 dB (piston radius = 0.032 m, frequency = 8000 Hz). (I have not checked my work thoroughly so there may be mistakes in my calculations.) You can see that the radiation pattern can be modulated by the deflection shape of the diaphragm. Tectonic's idea of the BMR is to apply these properties, with diaphragms constructed to flex in a controlled shape during operation to widen its directivity beyond what a rigid piston can provide. Also, from the mathematical models, you may see the reasoning behind why the BMR diaphragm is flat and has no dust cap.

[Edit] Corrected error. Normalization of the polar directivity plot is for maximum response, not the on-axis response.

 

[sarumbear]

You can look up Google scholar on bending wave loudspeakers and distributed mode loudspeakers, the technology the Tectonic BMRs are based on.

According to Tectonic they are using the technology used in NXT speakers. The technology is different to standard electromagnetic drivers only in diaphragm structure. Tectronic merged standard piston action with BMR method using a mechanical crossover system; they could to that because other than the differences in dispersion pattern they have the same efficiency as standard electromagnetic drivers as the energy conversion method is the same.

Tectonic Audio Labs

www.tectonicaudiolabs.com

 

[computer-audiophile]

The vintage SABA Greencone tweeter I have often used is also described as a bending wave design. The membrane is fixed in the middle with a brass screw and the voice coil starts in a radius a little further out, so that the membrane does not move piston-like as usual.

Photo taken from troelsgravesen

 

[sarumbear]

The vintage SABA Greencone tweeter I have often used is also described as a bending wave design. The membrane is fixed in the middle with a brass screw and the voice coil starts in a radius a little further out, so that the membrane does not move piston-like as usual.

Photo taken from troelsgravesen

View attachment 288794

Interesting device. However, it is still an electromagnetic driver using the same energy conversion method, hence have the same low efficiency.

 

[mhardy6647]

I thought Totschlag was sort of the German equivalent of the most direct meaning of
coup de grâce.

The precision of German compound nouns can be thrilling.

 

[computer-audiophile]

I thought Totschlag was sort of the German equivalent of the most direct meaning of
coup de grâce.

The precision of German compound nouns can be thrilling.

As I just read in an interview of T.C. Boyle, he says, "Translating my books into German makes them a third longer."

 

[dguillor]

DML's and BMR's, they use a sort of "exciter" on a panel/diaphragm. I am not well-informed on how they produce sound, but they promise a directivity wider than "standard" designs with the same diameter.

My experience is that a DML speaker has to be considerably larger for the same low frequency.

 

[Petrushka]

According to Google translate, "tot" = "dead, "schlag" = blow. And "Totschlagargument" = "killer argument". In English a "killer argument" is an argument that kills all other arguments, because it is so effective and irrefutable. In German it means the opposite?

It means argument killer.

 

[JiiPee]

Audium from Germany has a rather interesting speaker line based on a fullrange driver and an integrated downward firing subwoofer. Their smallest tower model has a 3" fullrange driver and a 6" x 9" subwoofer, and their largest model has a 4" fullrange driver and an 11" subwoofer. Besides in 4 different sizes the speakers come in four different concepts: a passive one, active subwoofer + passive fullrange driver, fully active with integrated DSP, and active wireless with integrated streamer.

Here is the frequency response measured by the German magazine "STEREO" for the smallest active tower model. It does look quite decent, and of course with integrated DSP one can play with it. It has fairly limited SPL capabilities though, but I guess that's where the bigger models with bigger drivers and amps improve things.

 

[hex168]

What would qualify as extreme nearfield for you?

Sorry I did not see this post at the time. Maybe within half a meter; whatever distance is needed to achieve a low-distortion output at a high enough level for the user. Another factor is the ratio of direct to reflected sound, which needs to be high so that the difference in frequency response between on and off axis is less important. I remember a design from the 1970's of an fiberglass egg-shaped chair, upholstered inside, with a full-range driver for the left and right channel built in. It worked well. I wish I could remember who made it.

 

[kemmler3D]

It does look quite decent,

On-axis looks decent, off-axis starts beaming at 5khz... not ideal really, but might sound OK in-room anyway since it has a rising response on-axis.