What role should listening play in speaker design

[Everett T]

Which speakers have you designed?

Other than a couple of DIY speakers? I was speaking about my experience from being around other designers and my opinion on the question asked more than anything. Also, their should have been a "would" used in this sentence "These are genres I use to finalize the speakers", it was well into the am when I replied.

 

[kemmler3D]

I'm hearing something, but I can't trust my hearing. I've got to trust the curves. And that's what kills me. 'Just trust the curves.' No, I'm not going to trust your curves."

I think this is an interesting thought but I don't really agree with it.

If you hear something, and you're a professional on his level, you should immediately have one or two hypotheses as to the cause. If it's not showing up in one curve, you would start checking other curves.

If it's not worth identifying the cause, is it worth fixing?

 

[SigbergAudio]

My only issue I have is that:

1. "You don't know what source is supposed to be." that's nonsense. The source is the source, whether the source was compromised or not, the source is the starting point and is the truth in sound reproduction. If you are going to question the source material and then try to compensate for what you believe is right, that is by definition the circle of confusion. Which is why every control room should have a linear in room response such that creating the source material is mixed and mastered in one standard and the playback is also in the same standard. So this is absolutely nonsense what AJ is saying.

"The source is the source". What does that mean in the context of tuning a loudspeaker?

1. He can't trust the measurements because of the inherited flaws due to the complexity, then why not just do a better job with the measurements? If it's costs, that's fair. Unfortunately, starting a new business is not cheap and for those companies who invested upfront, they get to reap the benefits.

"Why not just do a better job with measurements".

With respect, I'm always a bit baffled by people who readily throws critique about how others in a subject or industry that is not their own does their job. Somehow assuming whatever they're doing can be improved by "just" doing so and so.

 

[kemmler3D]

With respect, I'm always a bit baffled by people who readily throws critique about how others in a subject or industry that is not their own does their job. Somehow assuming whatever they're doing can be improved by "just" doing so and so

I can agree with this. Doing a proper set of speaker measurements takes hours, even with the Klippel it takes a long time. You can make changes and listen to them WAY faster than you can measure results.

I'm fully in the measurements camp. but boy would it take a long time to design a speaker if you did a full set for every change...

 

[Keith_W]

1. "You don't know what source is supposed to be." that's nonsense. The source is the source, whether the source was compromised or not, the source is the starting point and is the truth in sound reproduction. If you are going to question the source material and then try to compensate for what you believe is right, that is by definition the circle of confusion. Which is why every control room should have a linear in room response such that creating the source material is mixed and mastered in one standard and the playback is also in the same standard. So this is absolutely nonsense what AJ is saying.

I agree with you. But it's probably closer to say that the source (i.e. recordings) likely follow a normal distribution curve of tonal tilts with the mean being absolute neutrality. The problem is that there is no objective standard for neutrality for recordings. If this AJ guy happens to have a selection of recordings in the upper 25% that leans bright, and he adjusts his speakers to restore neutrality, that will mean that the speakers will sound too dark for the remaining 75% of recordings.

The ONLY source that can be GUARANTEED to be neutral are test signals. I have heard so many REW sweeps that I can tell from listening to the sweeps alone what the tonal balance is likely to be (I use that as a pickup line for women I meet in bars).

 

[PristineSound]

"The source is the source". What does that mean in the context of tuning a loudspeaker?

Good point, I would like to ask AJ what he means by not trusting what the source ought to be. Frankly, I don't know why he even brought this topic up.

You are essentially asking me what is the point of me bringing this up? I wonder the same why AJ brought it up.

My point is, the source is the source, there is no discussion here as it pertains to speaker design as you mentioned. So need AJ to tell us why he needed to bring this up.

"Why not just do a better job with measurements".

With respect, I'm always a bit baffled by people who readily throws critique about how others in a subject or industry that is not their own does their job. Somehow assuming whatever they're doing can be improved by "just" doing so and so.

I respect that. But you didn't quote everything I said though: "If it's costs, that's fair. Unfortunately, starting a new business is not cheap and for those companies who invested upfront, they get to reap the benefits."

 

[SigbergAudio]

My point is, the source is the source, there is no discussion here as it pertains to speaker design as you mentioned.

You still didn't explain what your point is by saying "the source is the source".

The concept of "the source is the source" or a term like "linear" is easy to talk about when we discuss electronics. What comes in should come out, right?

With loudspeakers this suddenly is not so simple. Which it seems like we find it convenient to ignore in some of these discussions. A speaker does not live in a void in the same way as an electronic component like a DAC or a streamer does. It is part of a complex system made up of the speaker, the room and the listener. As anyone who has ever seen an in-room measurement can testament to, the result is never linear. Further, we even know that we don't WANT it to be linear, as a flat response in-room does not portray an accurate representation of the original tonality.

Through all of this, there's no true way to know "what it should sound like" when listening to a produced track. The "correct" sound of the source is to some extent unknown. I have no idea if this is what AJ alluded to.

TL;DR: This is way more complicated/complex than many of you are making it out to be in these discussions.

 

[PristineSound]

You still didn't explain what your point is by saying "the source is the source".

The concept of "the source is the source" or a term like "linear" is easy to talk about when we discuss electronics. What comes in should come out, right?

With loudspeakers this suddenly is not so simple. Which it seems like we find it convenient to ignore in some of these discussions. A speaker does not live in a void in the same way as an electronic component like a DAC or a streamer does. It is part of a complex system made up of the speaker, the room and the listener. As anyone who has ever seen an in-room measurement can testament to, the result is never linear. Further, we even know that we don't WANT it to be linear, as a flat response in-room does not portray an accurate representation of the original tonality.

Through all of this, there's no true way to know "what it should sound like" when listening to a produced track. The "correct" sound of the source is to some extent unknown. I have no idea if this is what AJ alluded to.

TL;DR: This is way more complicated/complex than many of you are making it out to be in these discussions.

Ok, let me ask you this in return: if I don't know how the source "correct" sound ought to be, then what makes you think anyone's interpretation and decision of how the source should sound like? In other words, just because no one knows how the "correct" sound is as you are saying, does that mean a speaker designer gets to decide?

 

[TimVG]

I'm fully in the measurements camp. but boy would it take a long time to design a speaker if you did a full set for every change..

No thanks!

Better to measure the drivers seperately and use simulation. Verify the measurements at a number of angles with an active test filter and if the results match.. you're good to go. If not, improve your measurements

 

[RickS]

After some member questions, decided I needed to get some first-hand experience with the interview video in the OP. Overall, I thought AJ was credible but perhaps avoiding answers that might taint him in some way. Thought he would make a good politician. When asked about Dr. Toole, he would only say he worked for him in the past.

The interviewer clearly had an agenda. He asked about reviewers who only measure the gear (implying speakers)? Are there really any? AJ disavowed rather than pushing back. He asked about how distortion could be bad when musicians utilize it? AJ initially pushed back strongly to only later allow for some who like euphonic distortion.

My real eye opener was not here, but JJ's AES presentation on hearing. How our hearing decline really starts in our 20s. So really do struggle with aging speaker designers that claim how important listening is but somehow still want you to trust their hearing. Am willing to accept the value of experience but it cannot offset the reality of age-compromised hearing loss.

 

[Audionaut]

I have heard so many REW sweeps that I can tell from listening to the sweeps alone what the tonal balance is likely to be (I use that as a pickup line for women I meet in bars).

That's incredibly impressive, Keith. What's your success rate at bars?

what makes you think anyone's interpretation and decision of how the source should sound like?

As Keith already mentioned, it’s best to use a clearly defined signal for testing and level setting. As objective as possible—so no concerts, no musical pieces, no shattering glass, no church bells—even though such sound examples can be impressive and interesting if all listeners are equally familiar with them and can evaluate them consistently.

No, the most useful options are completely objective test tones that produce a defined signal. For identifying resonances and testing your own hearing, a frequency generator is ideal—one that allows you to play any frequency at the same level in 1 Hz increments.

For leveling and measurement, I use defined logarithmic sweeps in REW and ARTA across various frequency bands, and my personal reference signal for subjective evaluation is pink noise, whose energy roughly corresponds to human perception. I listen to this on every system, every pair of headphones, and every speaker, and in my opinion, it is excellent for identifying coloration, but also faulty radiation.

 

[mns3dhm]

It's certainly worth noting that this thread has generated 16 pages of responses in short order, so ASR members are actively engaged. Speaker design and development is an iterative process although we as end users seldom know how many design prototypes (real or CAD) or iterations a speaker went through before the design is finalized and production begins. Once physical prototypes can be evaluated the designer may decide to experiment with driver, crossover, or cabinet materials and listen to the results out of curiosity or to confirm the measurements and listening experience are the same. If the designer's ears are telling them one thing and the measurements tell a different story, then I would expect another iteration of prototyping would be necessary.

 

[RickS]

It's certainly worth noting that this thread has generated 16 pages of responses in short order, so ASR members are actively engaged. Speaker design and development is an iterative process although we as end users seldom know how many design prototypes (real or CAD) or iterations a speaker went through before the design is finalized and production begins. Once physical prototypes can be evaluated the designer may decide to experiment with driver, crossover, or cabinet materials and listen to the results out of curiosity or to confirm the measurements and listening experience are the same. If the designer's ears are telling them one thing and the measurements tell a different story, then I would expect another iteration of prototyping would be necessary.

Only if the designer owns the company or is a smaller operation, they may get the luxury of iterating. If a larger, contemporary operation, every day a speaker is not shipping is lost revenue. A speaker designer better be able to justify a need for iterating to management or it is going to ship with its “flaws”! Time to market is a really key driver in many product development jobs.

 

[Newman]

TL;DR: This is way more complicated/complex than many of you are making it out to be in these discussions.

Here is an uncomplicated question and issue: how old are you?

cheers

 

[PristineSound]

Only if the designer owns the company or is a smaller operation, they may get the luxury of iterating. If a larger, contemporary operation, every day a speaker is not shipping is lost revenue. A speaker designer better be able to justify a need for iterating to management or it is going to ship with its “flaws”!

When I was a teenager, I used to work at a regional electronic chain store. I have a love/hate relationship with speakers. The profit margin is typically 40% to 50%, the highest of any HiFi equipment, which is why I loved it, because of the commission and when I needed to buy, I pay half off. I hated it now because I don't get to buy at store cost, and speakers typically has to sell for about 5x the cost of manufacturing it to be profitable. So that means, we the consumer are paying the dealer, the salesmen, the distributor on top of the speaker manufacturer.

Because of this, I prefer to buy from manufacturers who only sell direct. I will use Ascend Acoustic and Philharmonic as examples; they invested heavily in R&D and manufacturing. . .and still able to sell at an affordable price. Every time I see a manufacturer who sells direct, I applaud, every time I see a manufacturer converts to a dealer network, I cringe.

 

[kemmler3D]

Only if the designer owns the company or is a smaller operation, they may get the luxury of iterating. If a larger, contemporary operation, every day a speaker is not shipping is lost revenue. A speaker designer better be able to justify a need for iterating to management or it is going to ship with its “flaws”! Time to market is a really key driver in many product development jobs.

Can confirm. Most likely you start with a performance target based on a competitive assessment or consumer research, if you are lucky, and once the prototype hits the performance target, you go to mass production as soon as possible. An owner-designer is really the only person who starts with the brief of "come up with the best speaker you can with XYZ constraint". It's more likely that you are told "The buyer at Best Buy wants a competitor to XYZ but cheaper, we ship in 3 months." You do what you can to reach the performance target or beyond, but you probably can't add to BOM cost to exceed the performance target.

 

[SigbergAudio]

Here is an uncomplicated question and issue: how old are you?

cheers

I was born in 1978. So I'm old enough to start to lose track, but that should make me 48ish?

 

[SigbergAudio]

Ok, let me ask you this in return: if I don't know how the source "correct" sound ought to be, then what makes you think anyone's interpretation and decision of how the source should sound like? In other words, just because no one knows how the "correct" sound is as you are saying, does that mean a speaker designer gets to decide?

I would suggest the designer of a product gets to decide most everything about that product, yes.

 

[goat76]

Ok, let me ask you this in return: if I don't know how the source "correct" sound ought to be, then what makes you think anyone's interpretation and decision of how the source should sound like? In other words, just because no one knows how the "correct" sound is as you are saying, does that mean a speaker designer gets to decide?

Why would anyone not use well-known reference materials in a case like developing a loudspeaker?

I'm pretty sure AJ is developing his loudspeakers using all the necessary measurements, and after that, he probably listens to them using well-known reference material, songs that he has heard on many great loudspeakers over the years, and therefore has a pretty good sense of whether it sounds overly bright, too dense, lacks body, is recessed, or sounds too way forward. Things like that.

When I set up my speakers, I start by letting the REW measurements dictate the EQ filters. After that, I listened to all my favorite reference tracks for weeks, reference tracks I've been listening to for the last 30 years or so, which I have a pretty good idea of how they sound on other great audio systems. This is the period when I fine-tune the EQ settings and the overall balance, until all my reference tracks sound as I've heard them and how I know they should sound. I suspect this approach is fairly similar to how AJ fine-tunes his loudspeakers, as it's actually not that hard to hear if something doesn't sound quite right when using well-known reference material.

 

[PristineSound]

I would suggest the designer of a product gets to decide most everything about that product, yes.

I thought I was clear on your design method, but now I'm not so sure now.

If you feel that the designer gets to decide what is "correct" in face of uncertainty in the accuracy of measurements, then I think that is where many here are in disagreement, including myself. . .at least for expensive, reference level speakers.

For few hundred dollar speakers, I would be ok with that the designer getting to decide what is "correct" or not.

Anyway, this conversation goes on and on. But I think we know where each other stand in terms of opinion and this thread is a great conversation.