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Do high-efficiency speakers really have better 'dynamics'?

tuga

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Good post!

Agreed. As someone who records lots of sound (and I've been in recorded bands) I know what you mean.

Actually, one of the cool things about listening to the live instruments in the open park is that it's effectively sort of "anechoic" - especially if you aren't too far away. That's what was so interesting as there was no immediate reflective room surfaces to boost the sound at all, and yet those instrumental images were so big and full even without room boost.

And so true about the distant recording effect. Lots of audiophile recordings to me sound listless when they eschew closer micing.

I love vivid instrumental timbre, so I like to be close to live sound sources, and I'm fine with close micing for recordings.

Ultimately, as you say, all things considered it's amazing how good recordings can often sound. It's all tricks and illusion, so I am happy doing my part at home to add tricks to make things sound more convincing to me.

Close mic’ing picks up a lot of mechanical noises which are not audible from even the closest seats in the audience (of unamplified recitals and concerts).
It also changes the timbre of acoustic instruments somewhat because of the way they radiate at different frequencies.
Finally imaging and soundstage sounds a lot less realistic to my ears in multi-track recordings.

Ultimately it’s a matter of taste but for example I find Reference Recordings hyper realistic in an unnatural way.
 

MakeMineVinyl

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Close mic’ing picks up a lot of mechanical noises which are not audible from even the closest seats in the audience (of unamplified recitals and concerts).
It also changes the timbre of acoustic instruments somewhat because of the way they radiate at different frequencies.
Finally imaging and soundstage sounds a lot less realistic to my ears in multi-track recordings.

Ultimately it’s a matter of taste but for example I find Reference Recordings hyper realistic in an unnatural way.
The Robert Shaw and the Atlanta Symphony recording of the Mozart Requiem on Telarc is a recording which technically is probably more uncolored than usual, but the result is it sounds so much in the mud and lifeless that it's almost unlistenable. This recording needed microphones which had more of a tilt up in the high frequencies to bring it to life.
 

mhardy6647

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Very nice stuff. I like it. I have a sweet spot for those components.
First order is fine if you are not stressing the drivers too much. And in home listening, you are definitely driving those drivers nowhere close to their max SPL.
Nope, not stressing them much at all...
:cool:
 

richard12511

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And this is why I like exchanging personal impressions of how things sound.

Not everyone wants the same thing, but you can find some like-minded people who share an appreciation for similar characteristics in a sound system, who are "listening for what you are listening for, caring about what you care about" and so it can actually be fruitful to exchange notes like this.

Where I live we are inundated with live music - live bands of all sorts, from electric to folk to lots of jazz combos, are playing almost every day, on the streets, in the parks etc. Today I was in our nearby park and a jazz band was playing, standards like from Miles Davis etc. Drums, electric guitar, stand up bass, trombone, sax.

Like I usually do I closed my eyes to listen (and at different distances, and from various angles - in front of the band, the side, behind) and took in "what do these live instruments sound like?" As usual the first impression is "BIG." With lots of acoustic power. Everything sounds like the big, actual sized instruments they are. Even drum cymbals sound like the big discs they are when struck, with lots of richness, rather than the tiny, reductive little bursts of high frequency that stand in for cymbals in most hi fi systems. Sax and trombone were clear and dense, rich and rounded - not lazer-like image outlines, slightly diffuse in their image outlines, but full and dense, solid.

Drums had that dynamic aliveness you just don't get through hi-fi systems, snare sounded large and thick with a sense of "it's right there" texture.

Back to drum cymbals, I was struck reading Jonathan Valin's TAS review of MBL speakers, where he remarked: "Through the X’s, cymbals have something you rarely if ever hear with domes and membranes—a disc-like roundedness that makes them sound three-dimensional, just as they do in life."

I almost yelled out YES!!!

I'll never forget doing the rounds at a CES show, listening for any system that could sound close to real. None did. All sounded like cones and tweeters. Then I entered the MBL room, first time, a jazz piece was playing and the first thing that jumped out was the sound of cymbals.
They actually sounded, just as JV expressed. It was the first time I'd ever truly heard drum cymbals sound to me like real drum cymbals - big, thick, round, disc-like. My own MBL speakers, though smaller, did this as well.

These are the types of characteristics I seek in my own hi-fi experience, and what I push my own system toward as much as possible. I do it through choice of speakers, amplification, source, and playing with acoustics in my room (I can change around the liveness/deadness of any area in the room.

When I came home I cranked up my system, played similar music and closed my eyes and I'll be darned if it didn't have a lot of the qualities I'd just heard in the live music. Not true "live" sound of course, but enough of the character to allow me to slip in to an illusion of a performance.

BTW, the "texture" thing is one reason I sometimes prefer vinyl records (and my tube amps). It may be a bit of added distortion, but whatever it is, drum skins and snares on some vinyl can have more of that cut-through-the-air texture that I recognize and heard today from real drums.

I played some good drum recordings on digital first, but it was some of the drums on vinyl that had my brain click and say "now THAT has the gestalt of real drums!"

Anyway, some of us have found a similar "gestalt" coming from those Devore speakers. What some will immediately perceive as going off-neutral, another may perceive as reminding him a bit more of "live." For me, the combination of "texture" richness and the "heft" of sounds through those speakers do that.

I honestly don't know if the Devore sound would, for me, be cloying or tiring over time though, not having lived with a pair. I hope to try them out some day.

Drums are a tough one. Vast majority of speakers can't handle dynamics like that. My JTRs are the only ones I own that probably can(134dB max), but I'll still never get to hear it, as no recording has it. I get why it makes sense to compress that sound in the recording, but it does mean I'll likely never hear true drum dynamics at home.

I find live "images" kinda all over the place. In a concert hall, they're usually huge(due to the high ratio of reflected/direct sound). Speakers like the big MBLs might be closest to approximating the correct ratio, so I could see where their center image might be closest to "real". Other real life images are tiny, though. A good example is a person singing/playing guitar in a park(almost no reflections), so a very narrow dispersion speaker comes closest to matching the correct ratio of direct to indirect sound to produce that image. The ratio of direct/indirect sound very much depends on both the room and the instrument. Most real instruments disperse their energy more narrowly as frequency increases, so a speaker that does best on average is probably something in between. What that beam width is, I'm still trying to figure that out. I think I moving more towards having one of each(separate systems) rather than having the absolute best of one particular dispersion type. I think my beam-width preference changes based on genre, as well as whether or not I'm sitting strictly in the sweet spot, or moving around.
 

tuga

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The Robert Shaw and the Atlanta Symphony recording of the Mozart Requiem on Telarc is a recording which technically is probably more uncolored than usual, but the result is it sounds so much in the mud and lifeless that it's almost unlistenable. This recording needed microphones which had more of a tilt up in the high frequencies to bring it to life.

I don't know that particular Telarc recording but mic-pair distant mic'ed orchestral does sometimes sound a bit dark and muddled; such recordings would benefit from an accent mic or two, or a two-main plus two-ambience approach.
 

gnarly

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My big picture take on 'high dynamics', is that it simply requires high linear acoustic output throughout spectrum.
Output that satisfies the average SPL desired, and also the peak headroom needed to reproduce all peak signal components.

The often unspoken key condition is 'throughout the spectrum'.......
It takes driver displacement or horn loading for the low end, no getting around it imho.
It also takes surprisingly more high end peak capability than I'd expect.
And of course it takes an amp (or amps) that has sufficient balls to drive it all....(especially if the system is passive).


Ime, the icing on a high-dynamic capable rig, that strongly adds to the "jump factor", is spot-on time alignment.
By that i mean smooth flattish phase....again with the key condition 'throughout the spectrum'.

Where transients that are supposed to splash/clash/sing together, do so.

For me, high dynamic SPL, smooth flat phase, is an awesome thing to hear.
I love it so much, all my system builds are portable enough to be set up for outdoor listening, where it's easy to hear the benefits.
Scratch easy to hear....glorious to hear describes it better.
 

Tom Danley

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Rms causing loss of low-level detail is a hypothesis that can be originated from the idea that the mechanical resistance to movement sort of jams the movement of the cone, like stiction friction - needs a certain amount of force to make it move at all.

If this was the case, it would show up in distortion measurements. Distortion would show a massive increase at low spl levels - which, at least I have never seen on any driver, regardless of what Rms they claim to have seen from the specifications.

Low-level or low-spl detail and resolution is determined by linear properties, like frequency response, including resonances and radiation pattern. Speakers that sound good on very loud volume tend to sound better at low volume as well, simply because the radiation pattern of those speakers gives better attenuation of early reflections.
Hi
You are quite correct, static friction (or hysteresis) has an increasing effect with decreasing signal level while resistance is a damping force acting on velocity.

Since one can't easily measure " how accurate" reproduction is with music, there may well be "clues" to what's going on if one considers the known things that govern ones understanding a series of random words under adverse conditions.

In fact, the process of measuring speech intelligibility itself shows something (I think).
There is a language independent method of measuring / predicting speech intelligibility called STi and STIpa.
It uses (if i recall correctly) 7 frequencies in the voice range and measures the Modulation Transfer Function in each band and then processes a resulting number.
In commercial sound, for safety warning systems reaching a minimum level of intelligibility can be a legal requirement now.

The explanation for modulation transfer function in optics works pretty well for the audio process

https://www.edmundoptics.com/knowle...introduction-to-modulation-transfer-function/

Here, high resolution means the sound is totally on and totally off and low resolution means there is sound where there shouldn't be.

The more the details are blurred by sound that shouldn't be there at that moment in time, the less able one is to understand random words in a large scale and the more the original stereo image is corrupted with late and conflicting information imparted AFTER the recording in the living room scale.

In the mid 70's, i worked at a small amplifier company called Grommes for a few years and Al the engineer believed that high efficiency speakers were better because of the efficiency. It was because if one had a 1% efficient speaker, 99% of the energy was lost in various mechanical and electrical losses, few of which are linear. On the other hand, a 25% efficient horn means only 3/4 of the energy is lost to those things so there is a lot less room for distortion.

I think what we have is a situation where many things enter into what we hear at any given time and what we hear is through a learned system that takes the goofy stuff one see's with "in ear" responses and turns that into our 3d audio experience.
Our hearing is also information seeking (and discards noise) and it's not something you can turn off. But if one listens to a measurement mic with good headphones (defeating the 3d hearing process) one can usually hear sonic warts in loudspeakers you never noticed before.
Best
Tom Danley
 

mocenigo

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I am speculating here but what about narrow directionality in horns causing a high direct:reflected ratiio? Regarding inreased dynamics, having a damping wall behind traditional speakers opened my ears to a new level. (I do not have this today due to estethics though.)

If depends on the type of horn. If you use a CD waveguide you can have a nice wide dispersion.
 

mocenigo

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I don't think crossover components would have much to do with it.
Heavy crossovers, with a lot of compensation cells (like those designed by Tony Gee), will sap current reducing sensitivity further.
Personally, I don't so much get a sense of increased 'dynamics' with horns - I would say that horns give a better sense of immediacy i.e. that the performers are present in the room compared to other speaker types, which tend to sound sort of 'distant' or 'detached' comparatively.

Many classic horns are quite directive, giving the effect of being between giant headphones. The sound is very forward. More modern waveguides have a more laid back sound, approaching that of non-horn loaded dynamic drivers, with advantages in terms of better directivity control (and also lower high order modes).
 
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tuga

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I don't think crossover components would have much to do with it.

Personally, I don't so much get a sense of increased 'dynamics' with horns - I would say that horns give a better sense of immediacy i.e. that the performers are present in the room compared to other speaker types, which tend to sound sort of 'distant' or 'detached' comparatively.

What you call "immediacy" I call "realism" or "liveness" and someone else quoted Holt describing it as "jump factor". And perhaps for that's what some people mean when they use the word "dynamics".

In my view, perceived "dynamics" require high low-level signal resolution, low distortion at high levels, "snappy" response to transients (hard to characterise) and minimal interaction with the room both above and below Schroeder (for fast decay, sharp imaging and good intelligibility).
 

Plcamp

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Is there a correlation between high efficiency speakers and the settle time seen on waterfall charts? Ie are higher efficiency speakers moving less mass, having less stored energy, settling quicker and that is what makes “dynamics” better?
 

Tom Danley

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If depends on the type of horn. If you use a CD waveguide you can have a nice wide dispersion.
If one considers the MTF explanation for optical systems, it is in fact the corruption or reduction in the difference between on and off portions which harm resolution. For voice intelligibility (which seems to be where our ears are most suited) the Hopkins / Stryker rule of thumb for intelligibility was use the fewest sources, with the greatest directivity, aimed at the ears and not the walls.
While one can measure and predict intelligibility now with tools like STI and STIpa measurements, these are also based on the MTF measurements but in sound.

Fwiw, a CD horn is one where the angular dispersion is more consistent over a wider frequency range than the curved wall types.
On axis, this doesn't matter as what you hear (assuming the same frequency response etc) is the same but the CD horn projects the highs to a wider angle and so is more suited for a larger seating area.
On the other hand, the more truly it is CD, the less focusing of the highs on axis and so the response must be eq'd to be flat.
The issue is even the best compression drivers have a power response which rolls off at a few KHz and with a true CD horn, that is the frequency response.
Both types can reduce the room contribution and can make the "near field" zone larger (where the direct sound is much greater than the reflected sound).
Tom
 

MakeMineVinyl

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Many classic horns are quite directive, giving the effect of being between giant headphones. The sound is very forward. More modern waveguides have a more laid back sound, approaching that of non-horn loaded dynamic drivers, with advantages in terms of better directivity control (and also lower high order modes).
The 'giant headphone' effect is exactly what I have gone for. The proof that I achieved that is that binaural recordings work just as well over these speakers as over headphones. However the sound is not 'very forward' - this problem is something I worked on for years to eliminate. Wide dispersion is something I specifically don't want or need. I want to hear the recording, not the room.
 

gnarly

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If one considers the MTF explanation for optical systems, it is in fact the corruption or reduction in the difference between on and off portions which harm resolution. For voice intelligibility (which seems to be where our ears are most suited) the Hopkins / Stryker rule of thumb for intelligibility was use the fewest sources, with the greatest directivity, aimed at the ears and not the walls.
While one can measure and predict intelligibility now with tools like STI and STIpa measurements, these are also based on the MTF measurements but in sound.

Fwiw, a CD horn is one where the angular dispersion is more consistent over a wider frequency range than the curved wall types.
On axis, this doesn't matter as what you hear (assuming the same frequency response etc) is the same but the CD horn projects the highs to a wider angle and so is more suited for a larger seating area.
On the other hand, the more truly it is CD, the less focusing of the highs on axis and so the response must be eq'd to be flat.
The issue is even the best compression drivers have a power response which rolls off at a few KHz and with a true CD horn, that is the frequency response.
Both types can reduce the room contribution and can make the "near field" zone larger (where the direct sound is much greater than the reflected sound).
Tom

Hi,
I've been struggling to find measurements that can explain differences in clarity with some of my DIY MEH/synergy speaker builds.

Mag and phase transfer function traces are all closely flat on axis, and very similar off axis.
THD differences seem minor at most. I've been studying how to make dual-tone and mutli-tone measurements, to try to see if IMD can explain the clarity differences. But that's all i've come with, and so far it hasn't been productive.

Your posts on STI and STIpa measurements have sent me to the Smaart manual, with the idea this may be a good measurement avenue, if i can make such measurements. Seems like MTF measurements might be telling.
Particularly so, since the clarity improvements have been most noticeable with vocals. Backing vocals (that i often didn't realize were there, doubly so.
I've also noticed with the clarity increase, sound seems both quieter and louder at the same time...more dynamic....if that makes any sense. (Critical listening is outdoors.)


My question is, do you think STI or STIpa, could produce measurements to help explain such clarity differences, when measurements are made outdoors as quasi-anechoically as possible?

Thank you, Mark
 

Tom Danley

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Hi,
I've been struggling to find measurements that can explain differences in clarity with some of my DIY MEH/synergy speaker builds.

Mag and phase transfer function traces are all closely flat on axis, and very similar off axis.
THD differences seem minor at most. I've been studying how to make dual-tone and mutli-tone measurements, to try to see if IMD can explain the clarity differences. But that's all i've come with, and so far it hasn't been productive.

Your posts on STI and STIpa measurements have sent me to the Smaart manual, with the idea this may be a good measurement avenue, if i can make such measurements. Seems like MTF measurements might be telling.
Particularly so, since the clarity improvements have been most noticeable with vocals. Backing vocals (that i often didn't realize were there, doubly so.
I've also noticed with the clarity increase, sound seems both quieter and louder at the same time...more dynamic....if that makes any sense. (Critical listening is outdoors.)


My question is, do you think STI or STIpa, could produce measurements to help explain such clarity differences, when measurements are made outdoors as quasi-anechoically as possible?

Thank you, Mark
Hi
It might but some years ago i had the opportunity to ask Sander, the fellow who was presenting about STIpa if it could apply to music reproduction system. His answer was noncommittal and emphasized that a reduction in intelligibility can be from many things like the microphone and everything else including the room, loudspeakers, their directivity and locations.

Personally I believe since our hearing appears to be fine tuned around locating the voice, that they are touching on something related to quality, at least within the voice range where the STIpa measurement operates.

I do know that taking a STIpa measurement directly in front of a loudspeaker, even that it is rarely ever a 1 and as soon as you move farther, it goes down

Winkiedinkiepedia has a decent blurb on it.

https://en.wikipedia.org/wiki/Speech_transmission_index

ARTA does have a Modulation Transfer Function measurement but the display would only be useful comparing one case vs another as there is no library of standard MTF's for other speakers etc. For A vs B, it would be fine.
A generation loss test also brings out the flaws in a way they stand out and also makes a nice side by side comparative tool.
Best,
Tom
 

kyle_neuron

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One thing to be aware of is that in recent years, the STI and STIpa metrics are subject of quite heavy debate and calls for review or major revision.

As a general rule, I find that systems which perform well by that metric also perform well in other areas, but I can also see how you can get a high STIpa score but also sound terrible for music - see many, many airports or similar.

The MTF values obtained are as much an aspect of the installation; room, placement, aiming, and the like as they are a speaker. I do remember the guys at the Roland Garros stadium repeating their test processes, as they simply didn’t believe that one of your boxes scored so highly, though :)

There are various ‘reproduction quality’ quantifying research attempts out there, but I don’t think many of them are even approaching the stage of ‘accepted consensus’. There’s a really interesting one for bass reproduction, but the algorithm or toolkit seems to be closed off as yet; that might be due to it needing more work, of course. It’s used in the Kolbrek & Dunker horn book for some analysis, and a few other papers I’ve come across.

It was one of my first choices for thesis topic, but the pandemic, plus concerns about the ethics board approval from the university for exposure of listeners to high sound levels put paid to that…
 

gnarly

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Hi
It might but some years ago i had the opportunity to ask Sander, the fellow who was presenting about STIpa if it could apply to music reproduction system. His answer was noncommittal and emphasized that a reduction in intelligibility can be from many things like the microphone and everything else including the room, loudspeakers, their directivity and locations.

Personally I believe since our hearing appears to be fine tuned around locating the voice, that they are touching on something related to quality, at least within the voice range where the STIpa measurement operates.

I do know that taking a STIpa measurement directly in front of a loudspeaker, even that it is rarely ever a 1 and as soon as you move farther, it goes down

Winkiedinkiepedia has a decent blurb on it.

https://en.wikipedia.org/wiki/Speech_transmission_index

ARTA does have a Modulation Transfer Function measurement but the display would only be useful comparing one case vs another as there is no library of standard MTF's for other speakers etc. For A vs B, it would be fine.
A generation loss test also brings out the flaws in a way they stand out and also makes a nice side by side comparative tool.
Best,
Tom
Thank you for your kind reply,

I'm going to explore STIpa a bit, because it seems to me vocal clarity in recordings is maybe the best indicator i have for speaker building progress.
I may really like the sound.... tonality and dynamics....., of building & tuning efforts, but how do i even know tonality is accurate?
Whereas, the more i can understand vocals, and hear backing vocals with distinction, i feel like i must be doing something right.
(and can always adjust tonality to taste).

The ARTA and Smaart manuals, along with the link you gave, let me see it will be a while before i understand how to make STIpa measurements properly, and what they are saying. Seems like i need to understand them well enough to keep ambient noise, reflections, and reverb out, but keep speaker distortion in, for the purpose of speaker building.

It would be nice if there were a MTF data bass of other speakers. If A vs B shows repeatable differences that seem to tie to audible reality, I'll be very happy. Not really expecting much, just hopeful.


Thx for the reminder about generation loss recordings. Maybe someday i'll get something that's not drunk after 4 rounds !
Best indeed, Mark
 

gnarly

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One thing to be aware of is that in recent years, the STI and STIpa metrics are subject of quite heavy debate and calls for review or major revision.

As a general rule, I find that systems which perform well by that metric also perform well in other areas, but I can also see how you can get a high STIpa score but also sound terrible for music - see many, many airports or similar.

The MTF values obtained are as much an aspect of the installation; room, placement, aiming, and the like as they are a speaker. I do remember the guys at the Roland Garros stadium repeating their test processes, as they simply didn’t believe that one of your boxes scored so highly, though :)

There are various ‘reproduction quality’ quantifying research attempts out there, but I don’t think many of them are even approaching the stage of ‘accepted consensus’. There’s a really interesting one for bass reproduction, but the algorithm or toolkit seems to be closed off as yet; that might be due to it needing more work, of course. It’s used in the Kolbrek & Dunker horn book for some analysis, and a few other papers I’ve come across.

It was one of my first choices for thesis topic, but the pandemic, plus concerns about the ethics board approval from the university for exposure of listeners to high sound levels put paid to that…
Hi,

I can already glimpse how STI and STpa metrics are a subject of heavy debate. Lot's going on huh? Between unamplified vs amplified, with noise vs without, male vs female....how much bandwidth gets into the measurements and what weighting...all for starters...yikes!

The idea of 'reproduction quality' metrics is fascinating i think. It's like artificial hearing being told 'what to listen for', and then give an evaluation.
Like you say... i'm not holding my breath for an accepted consensus on 'what to listen for' lol

and thx, mark
 

Tom Danley

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One thing to be aware of is that in recent years, the STI and STIpa metrics are subject of quite heavy debate and calls for review or major revision.

As a general rule, I find that systems which perform well by that metric also perform well in other areas, but I can also see how you can get a high STIpa score but also sound terrible for music - see many, many airports or similar.

The MTF values obtained are as much an aspect of the installation; room, placement, aiming, and the like as they are a speaker. I do remember the guys at the Roland Garros stadium repeating their test processes, as they simply didn’t believe that one of your boxes scored so highly, though :)

There are various ‘reproduction quality’ quantifying research attempts out there, but I don’t think many of them are even approaching the stage of ‘accepted consensus’. There’s a really interesting one for bass reproduction, but the algorithm or toolkit seems to be closed off as yet; that might be due to it needing more work, of course. It’s used in the Kolbrek & Dunker horn book for some analysis, and a few other papers I’ve come across.

It was one of my first choices for thesis topic, but the pandemic, plus concerns about the ethics board approval from the university for exposure of listeners to high sound levels put paid to that…
Hi Kyle
I am not surprised, even if it were 100% on target, involving it as legal requirement makes it complicated right off the bat.

I think your right, what i recall is that the process used 7 voice range frequency bands where the MTF was measured and weighted to get "a number".
It's the Modulation Transfer Function at the heart of STIpa etc that may be useful, at least comparing one speaker against another.
This would involve measuring over a much wider bandwidth and to measure "only the speaker" perhaps on a short tower so you have enough space to let the inverse square attenuate the reflections.


Looking at the display for MTF in ARTA, it appears that lets say 500Hz, its a measure of how deep the "on vs off" periods are, as the modulation frequency or rate is increased.
Best,
Tom Danley
 

carewser

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Yes, although having a wide frequency response probably helps as well
 
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