Transient response.

[dfuller]

The terminology and the mathematics that exist to describe speaker performance are abstracts created to quantify what some perceive as the critical aspects of speaker performance. That being said, they may or may not be an accurate representation of that objective. In my college days, I learned that mathematics is a language that can lie, for example, one can represent a half full glass of water as 1/2F and a half empty glass of water as 1/2E. Mathematically, everyone would agree that 1/2F = 1/2E. But upon solving the equation we get E=F which has no semblance to reality whatsoever. The example is an exaggeration to be sure, but even subtle differences can cause mathematically solid constructs to be false in the real world. What I am saying is that the rule in my audio world is "if it sounds good, it is good" and vise-versa. There is a reason that more Hit records were mastered on the "terrible" NS-10m's than any other monitor, and that reason is that they handle the transients better.

No, those records were not mastered on NS10s. They may have been mixed on them, but definitely not mastered. Nor is that the reason. The reason is that they more accurately represented the average listener's home stereo than the big Augspurger or JBL or UREI mains do, which means, you guessed it, that there was less of a "circle of confusion".

 

[Studio Guy]

My mistake, I meant to say mixed, but I stand by my statement that the transient response is the reason. Home stereo frequency response is so all over the place that no one speaker could ever actually represent them. Perhaps you would enjoy reading more about the NS-10m here https://www.soundonsound.com/reviews/yamaha-ns10-story

 

[dominikz]

In my college days, I learned that mathematics is a language that can lie, for example, one can represent a half full glass of water as 1/2F and a half empty glass of water as 1/2E. Mathematically, everyone would agree that 1/2F = 1/2E. But upon solving the equation we get E=F which has no semblance to reality whatsoever. The example is an exaggeration to be sure, but even subtle differences can cause mathematically solid constructs to be false in the real world.

There is nothing mathematically surprising or dishonest with the 'E=F' result in the context of provided definitions. But I doubt this formulation of the half-full/empty glass problem would pass mathematical scrutiny

Anyway, nothing wrong with using that which floats your boat!

EDIT: Welcome to ASR!

 

[Studio Guy]

I also would like to comment on 'flat frequency response" which seems to be a something of a holy grail for many. I can take one of my flattest studio condenser mics and plug it in to a sound system that has been equalized flat using a spectrum analyzer and when the vocalist speaks into that mic the result is dull and muddy and bears no resemblance to the sound I hear when she sings with the system off. I think we need a better set of analytics to compare speaker performance.

 

[Studio Guy]

There is nothing mathematically surprising or dishonest with the 'E=F' result in the context of provided definitions. But I doubt this formulation of the half-full/empty glass problem would pass mathematical scrutiny

Anyway, nothing wrong with using that which floats your boat!

EDIT: Welcome to ASR!

Thanks for the welcome! I really enjoy discussing these thing with other audiophiles. Perhaps a better example of a solid mathematical construct being wrong in the real world is Einstein's theory of relativity, which has been proven false because the speed of light is NOT constant. Yet the scientists of the world decided (and I'm not making this up) to vary the length of the meter so that the speed of light could remain "constant" and the theory could still be true.

 

[Jim Matthews]

Perhaps a better example of a solid mathematical construct being wrong in the real world is Einstein's theory of relativity, which has been proven false because the speed of light is NOT constant. Yet the scientists of the world decided (and I'm not making this up) to vary the length of the meter so that the speed of light could remain "constant" and the theory could still be true.

Gee. You should be able to provide citations for things you didn't make up.

Please do.

 

[richard12511]

Perhaps a better example of a solid mathematical construct being wrong in the real world is Einstein's theory of relativity, which has been proven false because the speed of light is NOT constant.

Can you cite some specific (scientific) sources for this? Genuinely curious. I know that the "speed" of light differs based on the medium it's passing through, but that is explained by other physics, and it doesn't make what Einstein formulated false.

 

[Studio Guy]

I found it, https://www.sciencenewsforstudents.org/article/sometimes-light-not-so-fast, although it was proven earlier than this . as for the scientists changing the definition of the meter, it was done in 1983, supposedly for the purpose of greater accuracy, but what it actually does is allow them to infintesimally vary the length of the meter to keep the speed of light constant. Here is their statement:n 1983, the meter was given its present definition (partly for greater accuracy) as the distance light travels in a vacuum in 1/299,792,458 of a second. (See Figure 4.) This change defines the speed of light to be exactly 299,792,458 meters per second. The length of the meter will change if the speed of light is someday measured with greater accuracy. You can look it up.

 

[dfuller]

My mistake, I meant to say mixed, but I stand by my statement that the transient response is the reason. Home stereo frequency response is so all over the place that no one speaker could ever actually represent them. Perhaps you would enjoy reading more about the NS-10m here https://www.soundonsound.com/reviews/yamaha-ns10-story

I'm well aware of how NS10s behave, as I've used them many times (much to my dismay). They're a small sealed box with barely any low end and a weirdly tuned crossover (IIRC the designer went for the wrong target). The perceived transient response is a direct result of having barely any bottom end (they start rolling off a bit above 100hz) and the sealed design having less group delay than a bass reflex design.

And yes, home stereo frequency response is incredibly all over the place (hence the whole "circle of confusion" thing). But that's the thing about NS10s - they're a much closer system to your average home stereo system from the 1970s-80s than some massive wall-mounted Augspurgers or JBLs.

 

[Wes]

Time for Some Quantum Gravity

 

[Studio Guy]

Can you cite some specific (scientific) sources for this? Genuinely curious. I know that the "speed" of light differs based on the medium it's passing through, but that is explained by other physics, and it doesn't make what Einstein formulated false.

In his 1972 book; Science at the Crossroads, Proffessor Herbert Dingle, who earl on was a supporter of and a foremost authority on the theory, came to the conclusion that the theory was false and postulated this refutation which has never been successfully answered. "According to the theory, if you have two exactly similar clocks, A and B, and one is moving with respect to the other, they must work at different rates...i.e., one works more slowly than the other. But the theory also requires that you cannot distinguish which clock is the "moving" one; it is equally true to say that A rests while B moves and that B rests while A moves. The question therefore arises: how does one determine, consistently within the theory, which clock works more slowly? Unless this question is answerable, the theory unavoidably requires that A works more slowly than B, and B more slowly than A. Clearly, an impossible theory cannot be true.

 

[Studio Guy]

I'm well aware of how NS10s behave, as I've used them many times (much to my dismay). They're a small sealed box with barely any low end and a weirdly tuned crossover (IIRC the designer went for the wrong target). The perceived transient response is a direct result of having barely any bottom end (they start rolling off a bit above 100hz) and the sealed design having less group delay than a bass reflex design.

And yes, home stereo frequency response is incredibly all over the place (hence the whole "circle of confusion" thing). But that's the thing about NS10s - they're a much closer system to your average home stereo system from the 1970s-80s than some massive wall-mounted Augspurgers or JBLs.

I see you didn't read the Sound on Sound article I linked. so here are some excerpts from it: "
I suspect that the success came from the NS10's only really unusual feature: its iconic white bass/mid driver cone. The cone wasn't just unusual because it was white, of course, but thanks to the way it was manufactured. The vast majority of paper-based speaker cones are pressed from pulp using a mould — partly because moulding gives the designer the ability to specify a curved cone-profile, to enable a degree of tuning of the driver's frequency response and resonant behaviour. A cone with a curved profile will generally become less rigid towards its outer edge, so as frequency increases its effective radiating area and output level reduces. Designers often use this technique to delay the onset of directionality in bass/mid drivers, so allowing a higher crossover frequency than would otherwise be possible.The NS10's bass/mid cone was not pressed but 'curled-up' from flat paper sheet and then glued (look closely at the picture and you can see the join). The cone is straight-sided as a result, and the curl-and-join technique had two consequences for the performance of the NS10 bass/mid driver. First, the straight-sided form generally results in a driver with a rising frequency response, and second, while straight sides maximise rigidity, which would normally result in a cone with a strong 'bell-mode' resonance, the glued join acts as a damper (imagine a bell with a glued sawcut down the side: it won't ring much).

Thanks to its two reactive elements — the mass of the cone/coil and the combined stiffness of the driver suspension and the air in the cabinet — a closed-box speaker displays second-order (12dB per octave) high-pass filter characteristics. A reflex-loaded speaker, on the other hand, thanks to the extra mass element of the slug of air in the port and the slug's own reaction against the air in the box, behaves as a fourth-order filter (24dB per octave). All reactive filters display a delay in their response to an input that increases with their complexity. In-phase movement of the air in the port of a reflex-loaded speaker must occur a half cycle (180-degree phase shift) after movement of the driver cone. This kind of time delay is known technically as group delay; it's actually the phase change with frequency expressed as time.
Group delay is not some imaginary construct that helps acousticians feel important, it's real — and it means, for the reflex-loaded NS10 option, that a bass-guitar fundamental at 60Hz will arrive at the listening position around 9ms after the second harmonic at 120Hz. Put another way, and expressed as a distance, the low fundamentals of the bass guitar (and parts of the drum kit) will sound as if they are nearly four metres behind the rest of the band (you can insert your own bass player gag here). Low-frequency group delay doesn't only influence mix decisions: it also varies widely between speakers and, unlike low frequency level, which can be adjusted via EQ, once its influence on tracking or mix decision has been 'printed' to the mix, it can't be undone.

Generally, the NS10's waterfall performance reveals a speaker that achieves -40dB within 6ms. Most speakers will take twice that long and many, especially those designed to maximise bandwidth, longer still. With just two small resonant features in the waterfall plot up to 3kHz, Nakamura could justifiably consider his design for the NS10 bass-mid driver a success"

I lived through the 70's and 80's and the home stereos of the time put the majority of what passes for a home stereo today to shame. My pioneer cs99a's were great. But that is neither here nor there. The fact is you can't just make the statement that all home stereos had a lack of bass and that's why th NS-10M's were a good tool. The NS-10M will reveal the ugly in your mix, every time. Don't get me wrong, its not a good sounding speaker, but it's a great tool when you're mixing because EVERYTHING sounds good on some big ole studio monitors, but your mistakes will glare out at you from the NS-10's. As a recording engineer, I don't want a monitor that makes mixes sound good. I want one that highlights my mistakes.

 

[Studio Guy]

Time for Some Quantum Gravity

Question, is gravity a particle or a wave? Give an example.

 

[KSTR]

The <40ms CSD quote probably comes from this paper: https://www.semanticscholar.org/paper/The-Yamaha-NS10M:-twenty-years-a-reference-monitor.-Newell-Holland/137bc09b853ae8ae4392e24e8c4b93ec523aeb98

The Waterfall of the NS10 is indeed rather clean but you can take any other decent speaker with trouble-free midrange (when ported then with rear port unless the front port is well damped) and EQ it to the same target and the CSD looks the same. For example, #35 in the paper, the Westlake BBSM-5. A ported one obviously needs to go much lower than the NS-10 in order to be able to EQ it to the 12dB slope for long enough.

Vice versa, when you give the NS10 the response of a ported speaker by adding a 12dB high-pass (subsonic filter) it will look exactly like a true ported one. Often, ported active monitors have subsonic filters as well, some 2nd order, some 4th, yielding 6th and 8th order roll-offs which of course are "slow". Only way this doesn't have much impact is to move the roll-off to 30Hz and preferably even lower. A ported bookshelf mini-monitor with a 50Hz corner and 4th-order subsonic, so 8th order total (like the A5X), will always have lagging "weight" on bassdrums etc.

After all frequency response (mag and phase) <--> transient response still hold and will always hold. Linear Systems Theory cannot be cheated on.

As for CSD Waterfalls, a CSD is just slices of FFT's over time of the impulse with short windows (hence low resolution in the bass). The lower the level in the bass the faster the CSD drops below the "floor" in the plot and lower the order of the bass roll-off the more so as the ridge decays faster.
Comparative decay statements must be made with the passband response normalized (based on 1/2 or 1/1 Oct smoothing so as not to overcorrect the fine grain).
There are better methods to visualize the decay than old-fashioned MLSSA-style CSD. Frequency dependent windowing should be used for the slices and the time axis should be periods. And of course, as mentioned, made on the trend-line normalized response, not the raw response.

 

[Jim Matthews]

In his 1972 book; Science at the Crossroads, Proffessor Herbert Dingle, who earl on was a supporter of and a foremost authority on the theory, came to the conclusion that the theory was false and postulated this refutation which has never been successfully answered.

It was answered in 1971.

GPS and cloud computing are based on the result.
https://en.m.wikipedia.org/wiki/Hafele–Keating_experiment

 

[Studio Guy]

The <40ms CSD quote probably comes from this paper: https://www.semanticscholar.org/paper/The-Yamaha-NS10M:-twenty-years-a-reference-monitor.-Newell-Holland/137bc09b853ae8ae4392e24e8c4b93ec523aeb98

The Waterfall of the NS10 is indeed rather clean but you can take any other decent speaker with trouble-free midrange (when ported then with rear port unless the front port is well damped) and EQ it to the same target and the CSD looks the same. For example, #35 in the paper, the Westlake BBSM-5. A ported one obviously needs to go much lower than the NS-10 in order to be able to EQ it to the 12dB slope for long enough.

Vice versa, when you give the NS10 the response of a ported speaker by adding a 12dB high-pass (subsonic filter) it will look exactly like a true ported one. Often, ported active monitors have subsonic filters as well, some 2nd order, some 4th, yielding 6th and 8th order roll-offs which of course are "slow". Only way this doesn't have much impact is to move the roll-off to 30Hz and preferably even lower. A ported bookshelf mini-monitor with a 50Hz corner and 4th-order subsonic, so 8th order total (like the A5X), will always have lagging "weight" on bassdrums etc.

After all frequency response (mag and phase) <--> transient response still hold and will always hold. Linear Systems Theory cannot be cheated on.

As for CSD Waterfalls, a CSD is just slices of FFT's over time of the impulse with short windows (hence low resolution in the bass). The lower the level in the bass the faster the CSD drops below the "floor" in the plot and lower the order of the bass roll-off the more so as the ridge decays faster.
Comparative decay statements must be made with the passband response normalized (based on 1/2 or 1/1 Oct smoothing so as not to overcorrect the fine grain).
There are better methods to visualize the decay than old-fashioned MLSSA-style CSD. Frequency dependent windowing should be used for the slices and the time axis should be periods. And of course, as mentioned, made on the trend-line normalized response, not the raw response.

To say that if you changed the NS10 it would be like all the other speakers is rather disingenuous. It is what it is. Also, saying that the use of two or more two dimensional mathematical representations that do not contain a time element are the same as one that does is just simply wrong. All musical notes. whether bass guitar kick drum,piano or vocal, begin with an attack that has two components, a percussive higher frequency part and a lower frequency tonal part. One has only to look at the warterfall charts earlier in this thread to know that most of the studio monitors are producing a significantly delayed (60 milliseconds) tonal bass. But to be fair, in frequency response terms, they are delivering PLENTY of it.

 

[Studio Guy]

It was answered in 1971.

GPS and cloud computing are based on the result.
https://en.m.wikipedia.org/wiki/Hafele–Keating_experiment

This link does not even address what Professor Dingle is saying. According to the theory, all motion is relative. The plane, in the relativistic world, is just as correctly stated as being stationary, while the clock on the ground moves under it. In which case the result of the experiment should have been the opposite.
There is no GPS in the southern hemisphere, it doesn't work there. Why? Also, explain just how cloud computing relies on the theory of relativity.

 

[Jim Matthews]

This link does not even address what Professor Dingle is saying. According to the theory, all motion is relative. The plane, in the relativistic world, is just as correctly stated as being stationary, while the clock on the ground moves under it. In which case the result of the experiment should have been the opposite.
There is no GPS in the southern hemisphere, it doesn't work there. Why? Also, explain just how cloud computing relies on the theory of relativity.

Wow.

Check your meds.

 

[KSTR]

Exactly as I had explained. GD at >=50Hz (where it is really musically relevant) is the same for a closed box with 50Hz tuning and ported one with 25Hz tuning. So a low-tuned ported speaker is even faster that the NS10 and it actually delivers bass.

Mr. @Studio Guy, you may well be an expert in your field but in Linear Systems theory (and application) I feel you're a bit out of your element ;-)

 

[Studio Guy]

Wow.

Check your meds.

Well if you think I stated it wrong, perhaps you need a quote from the man himself from an address Albert Einstein gave at Princeton University. "What we mean by relative motion is a general sense is perfectly plain to everyone. If we think of a wagon moving along a street we know that it is possible to speak of the wagon at rest, and the street in motion , just as well as it is to speak of the wagon in motion and the street at rest. That, however, is a very special part of the ideas involved in the principle of Relativity" Most people doggedly believe this drivel because it is presented as "science" without bothering to learn the implications of the stated theory. Scientists have on more than one occasion departed from reality into a montage of mathematical equations which have no relationship to reality.