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Are speakers the Achilles heal in sound reproduction?

QMuse

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#41
Well, elcaps do distort with increasing voltage across their terminals (as when used in filters like those crossovers), as has been shown by Douglas Self. But certainly much less than the speaker they feed.

And what about coils with a non air core (e.g. ferrit core)? AFAIK they start to distort when the core is driven into saturation. The designer of the crossover has to make sure that this does not happen below specced power.
Although it is not that critical as one might think, IMO elcaps and non air cores should have no place in crossovers of high quality speakers. Unfortuntaely these days you can find them even in Revel F208 crossover.
 

thewas_

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#42
Once you apply EQ to passive speakers to correct their FR and phase response active technology doesn't sound that superior anymore.
From technical/theoretical point of view its not the same as for example you almost never have perfectly symmetric LR crossovers with passive designs and always have the additional distortions of the passive RLC elements.
https://www.grimmaudio.com/site/assets/files/1088/speakers.pdf
Practically though few can and implement very good passive loudspeakers with almost no audible problems in comparison.
 

QMuse

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#43
From technical/theoretical point of view its not the same as for example you almost never have perfectly symmetric LR crossovers with passive designs and always have the additional distortions of the passive RLC elements.
You don't need "perfectly" symmetric LR crossover, you need to have it inaudibly assymetric, and that is not that hard to achieve.

Additional distortion of the passive RLC elements? You lost me there. My opinion is inline with what @SIY said in his post:

"If the passive components don't individually distort, putting them together won't suddenly make them do so. Linear superposition."

Can you post a link to any measurements supporting your opinion that distortion of passive RLC elements matters?
 

A800

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#44
Room > speakers.
 

tuga

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#46
Vinyl cartridges are transducers so they also qualify as an Achilles heel. But vinyl players are flawed in other areas too.
 

thewas_

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#49
You don't need "perfectly" symmetric LR crossover, you need to have it inaudibly assymetric, and that is not that hard to achieve.
Well, where is the limit of perfection? :D If you want a perfect radiation pattern they must symmetric and have the form for a example of LR which the least passive loudspeakers have. How much deviation is audible or acceptable is a matter of subjectivity till tests in those direction are performed.

Additional distortion of the passive RLC elements? You lost me there. My opinion is inline with what @SIY said in his post:

"If the passive components don't individually distort, putting them together won't suddenly make them do so. Linear superposition."

Can you post a link to any measurements supporting your opinion that distortion of passive RLC elements matters?
Here are some that few seconds of googling gave, you can find much more if you want
http://www.aes.org/e-lib/browse.cfm?elib=14630
http://www.aes.org/e-lib/browse.cfm?elib=15294 (related to class-D amp output inductors but the mechanism is similar)
https://www.audioholics.com/loudspe...er-crossover-part-ii-measurements-conclusions
https://hificompass.com/en/projects/experiment/test-couple-iron-core-inductors
https://linearaudio.nl/sites/linearaudio.net/files/Bateman EW 08 2003 distortion v time v bias.pdf
https://www.diyaudio.com/forums/solid-state/5107-capacitor-distortion.html
http://stephan.win31.de/capdist.htm
 
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DWPress

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#50
Actually, I'd have to say they are indeed the "Achillies Heal" and anyone who disagrees can trade me right now their Revels, Magies or whatever for a nice vintage set of late 80's boom box speakers. :p

Bottom line, get the best sounding transducers you can afford for your predicted average dB level and listening environment first and then later sourcing the rest of your kit is far less painful and more revealing when you do. I wish I could say I was smart enough to do this from the beginning but it's alway the first advice I offer if asked. A crappy amp and source will still sound far better on a good speaker than an excellent amp and DAC will on aforementioned boom box speaker!
 

QMuse

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#51
Well, where is the limit of perfection? :D If you want a perfect radiation pattern they must symmetric and have the form for a example of LR which the least passive loudspeakers have. How much deviation is audible or acceptable is a matter of subjectivity till tests in those direction are performed.


Here are some that few seconds of googling gave, you can find much more if you want
http://www.aes.org/e-lib/browse.cfm?elib=14630
http://www.aes.org/e-lib/browse.cfm?elib=15294 (related to class-D amp output inductors but the mechanism is similar)
https://www.audioholics.com/loudspe...er-crossover-part-ii-measurements-conclusions
https://hificompass.com/en/projects/experiment/test-couple-iron-core-inductors
https://linearaudio.nl/sites/linearaudio.net/files/Bateman EW 08 2003 distortion v time v bias.pdf
https://www.diyaudio.com/forums/solid-state/5107-capacitor-distortion.html
http://stephan.win31.de/capdist.htm
I have taken time to read the 1st AES paper you qoted. While authors do describe a mechanism that can lead to non-linear distortion in capacitors due to the force betweeen plates causing compression in insulation layer which leads to altering the distance between plates thus altering the capacitance, unfortunately they didn't make ANY measurement to demonstrate the order of magnitude such effect has on todays capacitors used in XO networks. So, while in theory this sounds interesting I cannot really assign any practical value to this research.

Personally, I don't believe this impact to be of any consequence. Just try to imagine what effect would fluctuation in capacitance have in RF oscillators and similar electronics. @SIY , @DonH56 what is your opinion on this?
 
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amirm

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#52
In the process of building my dummy load to test amplifiers, typical power resistors limit SINAD to about 105 dB. They modulate the voltage drop across them due to complex interactions of heat and physical characteristics of the resistor. So you can assume that kind of distortion limit in speaker crossovers.
 

A800

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#53
Let me offer my version. :)

Below 300 Hz or so: room > speakers
Between 300 and 600 Hz or so: room=speakers
Above 600 Hz or so: speakers > room
Sounds reasonable.
 

QMuse

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#56
In the process of building my dummy load to test amplifiers, typical power resistors limit SINAD to about 105 dB. They modulate the voltage drop across them due to complex interactions of heat and physical characteristics of the resistor. So you can assume that kind of distortion limit in speaker crossovers.
Or maybe even slightly better as the power resistor you used for dummy load may be less precise and more prone to distortion than resistors used in crossover networks.
 

Blumlein 88

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#57
Actually, I'd have to say they are indeed the "Achillies Heal" and anyone who disagrees can trade me right now their Revels, Magies or whatever for a nice vintage set of late 80's boom box speakers. :p

Bottom line, get the best sounding transducers you can afford for your predicted average dB level and listening environment first and then later sourcing the rest of your kit is far less painful and more revealing when you do. I wish I could say I was smart enough to do this from the beginning but it's alway the first advice I offer if asked. A crappy amp and source will still sound far better on a good speaker than an excellent amp and DAC will on aforementioned boom box speaker!
This gets to the crux of it. The speakers will make the most difference in the sound you get. The room might or might not (ask about a metal 11ft square room). The speakers are a limiting factor, and the one that varies the most in terms of audible differences.

NOTE:I'm ignoring microphones and recordings at the other end of things, as we don't have any control over that other than don't listen to crappy recordings.

Everything between microphones and speakers can be audibly transparent (it isn't always, but can be). The transducers at each end aren't, and speakers vary more than microphones.
 

thewas_

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#58
Personally, I don't believe this impact to be of any consequence.
Again in a good design using properly dimensioned inductivities and foil capacitors their distortions will be so low that they will be masked by most loudspeakers distortions but that doesn't mean this will be always the case though as sometimes small iron cores and electrolytic caps are used.
Anyway this discussion was about the general and theoretical advantages of active vs. passive loudspeakers.
 
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