Is it possible to cover the whole spectrum, high SPL, low distortion with a 2-way?

I can't say anything here in general.
There are speakers with (very!) high sensitivity but a teeny weeny voicecoil and no cone excursion.
Which will (audible) go much quicker into compression, in fact they are even developed that way for that reason.
I assumed we were talking about drivers made for reproduction. Is the driver you mention, that goes quickly into compression, made for reproduction? I would not want that driver for reproduction. Your example looks like a guitar amp speaker.
 
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In my humble opinion - as recently reaffirmed - efficiency (lack of signal loss) is perhaps the single most determinant factor for the final sound quality.
high sensitivity does not equal low distortion. Think of a motor with a shrunk linear stroke: higher sensitivity but elevated distortion is the result.

The only common factors I can think of this late hour are high Sd which has its pros and cons and/or using super high saturation steel to increase the B field in the gap. Reducing Mms is a mixed bag since the driver gets less mass controlled and more sensitive to the non linear suspension.

As we have shown, it is perfectly possible to do ultra low distortion with low sensitivity. According to Hofmann’s Iron Law this results in small boxes that go deep.

Nothing wrong with high sensitivity and that can be done with low distortion also. We have no philosophy favouring. low sensitivity. We just only have 24 hours a day like everyone else. let’s see what the future brings.
efficiency is not any better than sensitivity as indicator of linearity
 
I can see why you are confused. I didn't ask the question correctly, the 2nd time after clarifying my use of "direct energy" that is, direct sound...

The part that mattered was that I am pointing to the omnidirectional part of the spectrum for each source

Source A; 4" 1m 50hz 86db
Source B; 18" 1m 50hz 86db
Source C; 24" 1m 50hz 86db

All are omnidirectional at this frequency, I believe. Will the larger radiation sources deliver higher Direct Sound levels, to the 1m listening point, in a room, is the question?

@gedlee
The best way to get more direct sound from an omnidirectional source is to stay away from room boundaries.
 
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I can see why you are confused. I didn't ask the question correctly, the 2nd time after clarifying my use of "direct energy" that is, direct sound...

The part that mattered was that I am pointing to the omnidirectional part of the spectrum for each source

Source A; 4" 1m 50hz 86db
Source B; 18" 1m 50hz 86db
Source C; 24" 1m 50hz 86db

All are omnidirectional at this frequency, I believe. Will the larger radiation sources deliver higher Direct Sound levels, to the 1m listening point, in a room, is the question?

@gedlee
Ok my question is still flawed... I try again

Will the larger radiation sources deliver higher direct sound vs indirect sound, in a room, when all source examples are playing in the omni spectrum, like in the above scenario of;
Source A; 4" 1m 50hz 86db
Source B; 18" 1m 50hz 86db
Source C; 24" 1m 50hz 86db

Spl being a sum of both direct and indirect

I'm almost certain its true. As we increase radiation area, less velocity is required from the driver to achieve volume velocity. There is more volume...more volume of direct sound
 
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I assumed we were talking about drivers made for reproduction. Is the driver you mention, that goes quickly into compression, made for reproduction? I would not want that driver for reproduction. Your example looks like a guitar amp speaker.
I understand that you don't want such a driver, me neither, but some people actually do, even for "reproduction" (which is a VERY vague word actually).

Anyway, my point was pure from a general perspective, that one can not just make a general statement about sensitivity in this context if the other parameters are not known.
As said before, it's not (always) a good parameter for how "good" a driver is.

High sensitivity is just a result of certain parameters of a speaker.
Which could result in a poor "reproduction delivery" if it's not done well, or good "reproduction delivery" when done well.
Or to be more reasonable, it doesn't necessarily means better performance/reproduction.
There are just to many other variables into play.

To say something about it, one has to look at all these other parameters as well.
When all things are equal (which is NEVER the case), and proper low frequency output isn't the goal, only than it could be an indication for better sound quality.

As a mentioned before, (and were the quoted text refers to), it all depends on context.
 
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I understand that you don't want such a driver, me neither, but some people actually do, even for "reproduction" (which is a VERY vague word actually).

Anyway, my point was pure from a general perspective, that one can not just make a general statement about sensitivity in this context if the other parameters are not known.
As said before, it's not (always) a good parameter for how "good" a driver is.

High sensitivity is just a result of certain parameters of a speaker.
Which could result in a poor "reproduction delivery" if it's not done well, or good "reproduction delivery" when done well.
Or to be more reasonable, it doesn't necessarily means better performance/reproduction.
There are just to many other variables into play.
The word reproduction is not vague. I did qualify my statement in post 10,989 - "To me, the thrill of higher sensitivity is lower compression. It's not the only parameter, but more heat = more compression." Of course there are other considerations. No single parameter guaranties better performance. I want it all. I'm a whole package kind of guy. 🙂
 
Ok my question is still flawed... I try again

Will the larger radiation sources deliver higher direct sound vs indirect sound, in a room, when all source examples are playing in the omni spectrum, like in the above scenario of;
Source A; 4" 1m 50hz 86db
Source B; 18" 1m 50hz 86db
Source C; 24" 1m 50hz 86db

Spl being a sum of both direct and indirect

I'm almost certain its true. As we increase radiation area, less velocity is required from the driver to achieve volume velocity. There is more volume...more volume of direct sound
OK. I'll take a stab at this. Assuming all sources are omnidirectional, the largest sources may appear more 'direct' because they are larger. A 24" driver at one meter is close to nearfield. The images in the nearfield will appear larger. Similar attributes could be said about close miking vs far miking, or listening to line sources vs point sources.

Multi-way speakers can take on strange image size reproduction if the drivers and/or layout are mismatched, There are a lot of ways to distort a sound image - some that people like.

I think the useful goal is to try to reproduce the intention of the recording in all cases. That is difficult.
 
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I think maintaining linear SPL across the spectrum at a person's volume preference is super important to SQ....
And I think in reality, volume preference is often heavily influenced by what our system can actually put out while staying linear.......
I mean who doesn't turn down the volume when it starts sounding stressed? Would you necessarily turn it down if it stayed clear and clean, louder?

When a speaker maintains linearity across the spectrum, including headroom for dynamic range and transients...it greatly adds to clarity and a sense of realism (to my ears).

When i run the numbers on what it takes to do that, I find that even at moderate volume, it takes more than is often acknowledged, ....possibly because folks seem to be OK with the idea "it will work for home audio levels". I think that idea often costs SQ.
I don't think there is anything to disagree with in what you really think, only with what you originally said 🙂

I have had and still have a system that does not really have enough excursion to go super loud without pushing the limits but it is never the bass that makes me want to turn it down, it's usually the change in mid and treble tonality at high volumes that makes me cringe. I am yet to find a tuning that works across the board level wise. I have two RSS390 15" subs that I have had for ages sitting in boxes that I will eventually use somehow but the desire to push it on quickly isn't there based on what I already hear.
 
I don't think there is anything to disagree with in what you really think, only with what you originally said 🙂
Without looking back carefully , I don't know of anything i said that i think was off target.
I know the idea of saying to avoid dsp to boost a sealed sub's low end response is counter to what folks do, and what is generally accepted as working fine. Probably does work fine for the most part.
I still think there's a better way. But so what, just my 2c......
I have had and still have a system that does not really have enough excursion to go super loud without pushing the limits but it is never the bass that makes me want to turn it down, it's usually the change in mid and treble tonality at high volumes that makes me cringe. I am yet to find a tuning that works across the board level wise. I have two RSS390 15" subs that I have had for ages sitting in boxes that I will eventually use somehow but the desire to push it on quickly isn't there based on what I already hear.

A well known phenom when doing prosound system check, is to play a track at an excellent sounding, super clean, high SPL...... smiles everywhere. 🙂
And then cut the subs off....everybody immediately makes faces or puts finger in their ears. 🙁
Then cut the low-mids/mids too, and folks run to get away, from ears hurting....😡
But the highs are still at the same original SPL. Why does it hurt?

Seems clear that tonality's balance is definitely a stress/fatigue factor. (and certainly a SQ factor)

Ime, if the low end can't keep up linearly with volume increase, sound goes to shite...and get's harsh.
I think such might be the biggest issue with home audio..
 
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high sensitivity does not equal low distortion. Think of a motor with a shrunk linear stroke: higher sensitivity but elevated distortion is the result.

The only common factors I can think of this late hour are high Sd which has its pros and cons and/or using super high saturation steel to increase the B field in the gap. Reducing Mms is a mixed bag since the driver gets less mass controlled and more sensitive to the non linear suspension.

As we have shown, it is perfectly possible to do ultra low distortion with low sensitivity. According to Hofmann’s Iron Law this results in small boxes that go deep.

Nothing wrong with high sensitivity and that can be done with low distortion also. We have no philosophy favouring. low sensitivity. We just only have 24 hours a day like everyone else. let’s see what the future brings.
ok, I talked about nonlinear distortion.

Room reflections, standing waves, baffle diffraction etc are linear effects (linear distortion). I will stay out of that can of worms for now😉

efficiency is not any better than sensitivity as indicator of linearity
Good points!
Reducing Mms should not be an end in itself, but should be weighed against other driver characteristics.

"... it is perfectly possible to do ultra low distortion with low sensitivity. According to Hofmann’s Iron Law this results in small boxes that go deep."
Sometimes, such small airpumps work surprisingly well, like the custom 6" (with in-house machined aluminum cone) in the YG Acoustics Cairn

Purifi drivers are undoubtedly SOTA in every respect, though small, relatively inefficient and above all: expensive.

This 12" does not measure as well as the Purifi PTT6.5, but good enough and is also 10 dB more sensitive.

1666914605791.png


You can buy 4 of these woofers + a pair of matching - also well-tested, compression drivers to build a set of 97-100 dB speakers... for less than the price of a single Purifi PTT6.5.
Low extension of that system is roughly equivalent to a Purifi-based 2-way monitor, but the listening experience will be completely different.
 
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Without looking back carefully , I don't know of anything i said that i think was off target.
Have a look and you should be able to see it, certainly there was a lot of confusion caused by some of your comments and I wouldn't have made a number of posts if what you said seemed right to me, I think it is all clear enough now not to worry about.
Seems clear that tonality's balance is definitely a stress/fatigue factor. (and certainly a SQ factor)
Absolutely, I don't find it to be a fixed quantity but more of a ratio, like in your example where if you cut the bass the treble sounds way too loud even though it hasn't changed. I find too much bass is obvious to me, there is a defined point when it just sounds wrong.

For a system that needs to play a wide range of SPL's some form of dynamic EQ seems necessary. The frequency balance you perceive varies at different levels making it impossible to have that balance the same at all levels without some form of dynamic EQ.

This is the reason why calibrated levels in mixing and mastering makes a lot of sense to me.
 
Hi mark100,

Without looking back carefully , I don't know of anything i said that i think was off target.
I do not have to look back, apart from for a reference to the exact posts, because the following statements did not agree with my understanding. To wit:

This is a quote form your post 10,928 (emphasis supplied):
If a sealed box's very low end is extended by increased excursion via EQ, the EQ invariably negates the sealed's natural low-order rolloff.
Transfers/achieved acoustic high-pass, head towards the same as vented, so might as well go vented.....
And from post 10,941 (emphasis supplied):
Bottom line imo, is both vented subs and EQing sealed subs to an equivalent response lead to same end, an extra two orders of so of phase rotation / group delay, vs straight sealed.
Do you still stand behind these statements?

Please do not misunderstand me, I am a proponent of sealed enclosures, I am just trying to understand your argument vis-a-vis the subsequent rebuttals.

Kindest regards,

M
 
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Really? What in such a system is causing it to sound differently balanced at different levels? Diffraction is one for which perception changes with level.
Diffraction could play a role but I think most of it is down to how your ears perceive the frequency balance at different levels. Something tuned carefully at a reference SPL sounds quite different 20 dB louder or 20dB softer. For me louder is the bigger problem. I generally prefer an overall down sloping in room response at anything up to about the 83dB mark but above that I tend to prefer the flat to 1K and then downslope after, I do not like that much at lower levels.

Mitch Barnett has spoken about it to
"As a former recording/mixing engineer, I use industry guidelines from the ITU and EBU to set up my speakers in an equilateral triangle, speakers toed in, on axis, pointing directly at my ears. I also calibrate my listening level, so when I am performing critical listening, I monitor at ~83 dB SPL, C weighting, slow integration, using a calibrated sound level meter. Bob Katz’s article that I linked, provides an excellent overview of the process and why. Most recording/mixing/mastering engineers use the same equilateral triangle setup and monitor level calibration for producing the art. I use the same approach for reproducing the art. For levels below 83 dB SPL, JRiver’s dynamic loudness control is engaged. Remember folks, our ears frequency response changes with signal level."
 
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I understand the role that the equal-loudness curves play in day to day life, and the desire to reproduce at the original level.. but that point is often overstated in my opinion. I've made the mistake myself. I feel that speakers which change with level within their normal range may have a linear distortion or room related issue.
 
We all have our opinions based on whatever created them. I'm not trying to convince anyone of anything but for me this has been a consistent issue across a wide range of speakers. The solution has been quite simple but awkward.

If you have something other than your experience vs mine I am all ears.