What role should listening play in speaker design

[a4eaudio]

Do you use ad-hoc, sighted listening tests to override what you see in measurements?

What does "sighted" refer to when voicing a speaker? The speaker designer designed the speaker, although it may be in an unfinished prototype cabinet, he knows what it looks like because he designed in.

 

[Jonazkur]

if i make speakers to myself then ofc listening is important. But if i made them for anothers then i would probably follow the data more. A well behaved speaker can be used with eq well so its easy to tweak.

 

[TimVG]

And yet... These old guys keep designing speakers that measure, sound, and sell well. It's almost like the keyboard prognosticators are wrong and the professional loudspeaker designers with decades of experience are right.

MoFi 8 and 888 look good. Some of the ELAC stuff though was a big swing and a miss. So much for consistency?

 

[Mort]

What does "sighted" refer to when voicing a speaker? The speaker designer designed the speaker, although it may be in an unfinished prototype cabinet, he knows what it looks like because he designed in.

As opposed to blind. Would that change your answer? You might be avoiding the question.

 

[a4eaudio]

That analogy doesn't really hold up anymore. It's more like, instead of a person throwing the dart, you have a fairly sophisticated robot that you have to program with the correct data.
The dart's trajectory, shape, and weight; air temperature; air movement; the distance to and height of the dartboard; and so on.
If all the data is correct, it will work.

It is quite easy nowadays to design a speaker that measures well. Just pick a target and run it through an optimizer. Why is it that not every speaker measures perfect and sounds great? And in fact, it seems somewhat uncommon to find speakers that measure and sounds great.

 

[Mort]

And in fact, it seems somewhat uncommon to find speakers that measure and sounds great.

Oh come on. That's simply not true.

 

[a4eaudio]

... Some of the ELAC stuff though was a big swing and a miss. So much for consistency?

I'm not sure when AJ left ELAC, but regardless I'm not aware of any of their speakers that haven't sold very well.

 

[a4eaudio]

Oh come on. That's simply not true.

Then why do people get so excited when something like Ascilab or Orbit comes out? They should be a dime, a dozen.

 

[TimVG]

It is quite easy nowadays to design a speaker that measures well. Just pick a target and run it through an optimizer. Why is it that not every speaker measures perfect and sounds great? And in fact, it seems somewhat uncommon to find speakers that measure and sounds great.

Because quite simply few designs allow for such "perfect" behaviour. Measuring a speaker accurately requires a lot of attention to detail as well.

 

[a4eaudio]

As opposed to blind. Would that change your answer? You might be avoiding the question.

When voicing a speaker, the designer may be listening to version A that he modelled and measures great, vs version B that has a 0.50 dB dip between 1kHz and 4kHZ and 0.50 dB higher above 10kHz. Where does "sighted™ or "blind" come into play?

Now, it may be a good idea to have A and B be randomized, as he may have some unconscious bias as to which he thinks SHOULD sound better, but that is a different issue.

 

[a4eaudio]

.... Measuring a speaker accurately requires a lot of attention to detail as well.

A commercial speaker designer can send the prototype to a professional anechoic chamber or a Klippel for practically nothing. Although I'd assume they, or someone on the product development team, are competent and measuring

 

[TimVG]

A commercial speaker designer can send the prototype to a professional anechoic chamber or a Klippel for practically nothing. Although I'd assume they, or someone on the product development team, are competent and measuring

There is quite a bit of difference between measuring a finished speaker and measuring drive units for crossover design. Just ask @RickS
The cost of practically nothing I would also say is an understatement.

 

[Lars Risbo]

In the same way that class D amp design guru Bruno Putzeys says that his new module sounds so and so compared to the old ones. Of course he doesn't believe that himself but for marketing, sales reasons he mentions it.

I dont recall Bruno saying what you state. on the contrary, he has said that the improvements in sound are diminishing returns and the amps are asymptotically approaching perfect. Also, how can you know what he believes?

 

[kimmosto]

The cost of practically nothing I would also say is an understatement.

Weight and size limits in anechoic labs can also be a problem. Small 2-ways are measurable anywhere, but weight of "proper" speaker is usually above 50 kg so no chances e.g. in Aalto University Helsinki.

 

[Sigberg Audio]

A commercial speaker designer can send the prototype to a professional anechoic chamber or a Klippel for practically nothing. Although I'd assume they, or someone on the product development team, are competent and measuring

Maybe 750-1000 euro for the Klippel measurement service. Shipping both ways for potentially heavy products on a pallet. Not nothing.

 

[a4eaudio]

Weight and size limits in anechoic labs can also be a problem. Small 2-ways are measurable anywhere,...

Good point!

 

[kimmosto]

...he has said that the improvements in sound are diminishing returns and the amps are asymptotically approaching perfect.

How about current driving of electro-mechanical transducers? It's kinda logical problem to design perfect voltage amplifiers while current driving can reduce non-linear distortion significantly (above system resonance) especially with active speakers. Of course, possibilities to clean sound with current driving depend on driver's sensitivity and linearity. I have done HD+IMD reduction with series resitance expecially when (compression) driver has too high sensitivity and dynamic headroom, revealing also noise at near field.

 

[kimmosto]

Current-Driving of Loudspeakers

 

[Lars Risbo]

current drive eliminates several distortion mechanisms. one of the exclusive tricks you can do in active speakers.

 

[Lars Risbo]

speaking of distortion: the desire to voice away from flat on axis can be due to distortion. eg making voices harsh and then a BBC like dip may soften it. With low distortion, i think that ruler flat on axis works best.