Yes it will ring for the reasons you mentioned. Although in any well designed motor the higher orders generally sit very far down. A 500Hz tone would require the 6th harmonic to excite it and there's generally not a lot of that going around, so you'd be safe.
With stuff like this it is usually only the third harmonic that is the offender and mainly for the reason above. If the second harmonic causes an issue, it's usually benign enough to ignore (as in 2nd order distortion is benign), but it's also higher up in frequency so is the first harmonic to be pushed off the radar via usual low pass filtering.
Drivers can produce copious amounts of third order distortion to start with, so if that is only at an acceptable level anyway, any cone resonance amplification of the third harmonic is usually a no go area, ie you have to cross significantly before it. Even if the driver has rather good third order performance, say with the third harmonic products at -55 to -60dB, the resonance can push this up to -35dB, which is clearly not particularly likeable and you definitely need to cross over lower than you would probably like to ensure that it isn't a 'problem'.
The fourth and fifth harmonics tend to be far enough down such that even after they have been amplified by the cone resonance they are still far enough down not to be considered a problem. (Typically at or below 0.1%).
With stuff like this it is usually only the third harmonic that is the offender and mainly for the reason above. If the second harmonic causes an issue, it's usually benign enough to ignore (as in 2nd order distortion is benign), but it's also higher up in frequency so is the first harmonic to be pushed off the radar via usual low pass filtering.
Drivers can produce copious amounts of third order distortion to start with, so if that is only at an acceptable level anyway, any cone resonance amplification of the third harmonic is usually a no go area, ie you have to cross significantly before it. Even if the driver has rather good third order performance, say with the third harmonic products at -55 to -60dB, the resonance can push this up to -35dB, which is clearly not particularly likeable and you definitely need to cross over lower than you would probably like to ensure that it isn't a 'problem'.
The fourth and fifth harmonics tend to be far enough down such that even after they have been amplified by the cone resonance they are still far enough down not to be considered a problem. (Typically at or below 0.1%).
In theory yes. Even someone playing the piccolo, in the same room as the loudspeakers, at 3kHz, would make the 3kHz resonance resonate in sympathy with it.
Haven't seen ceramic on the list (or diamond). They were Accuton's materials I think.
I don't have a favorite per se; just know I don't like metal on principle (not very objective I know).
Right now I have paper/fibre (Jantzen/AR/Hemptones), polypropylene and talc (Dynaudio), Kevlar (Scanspeak) and various textiles (Dynaudio, AR and CSS).
I don't have a favorite per se; just know I don't like metal on principle (not very objective I know).
Right now I have paper/fibre (Jantzen/AR/Hemptones), polypropylene and talc (Dynaudio), Kevlar (Scanspeak) and various textiles (Dynaudio, AR and CSS).
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It's perhaps not entirely fair to lump all drivers into quite specific categories but it essentially boils down to this.
1) Stiff, rigid cones that resonate and ring at a specific frequency and require an xover of at least 1/3 this frequency to work at their best. This includes diamond, all metals and ceramics.
2) Soft, well controlled, well damped cones that do not display the characteristic distortion amplification due to cone resonance of the rigid cones. This means drivers like scan speaks revelator slit paper series, scan speaks fibre glass cones, vifa's TC9, the Satori from SB acoustics, many poly cones etc.
3) Then this group, the composite materials, some weaves/adhesive blends, laminate cones, kevlar, carbon fibre and some paper blends. Anything really that is reasonably stiff but that also posses some decent internal damping. These tend to display ugly resonances, like the metal cones, but at lower frequencies than metal cones. The main difference here is that these cones tend not to amplify the distortion products. You may think this an advantage and it is, but because the resonances usually occur quite a bit lower than metal cones, they can interfere with where you'd want the driver to normally operate. If the driver is well designed it is still usable, but not as flexible as the soft cone and can usually be crossed a bit higher than the metal cone.
Composites tend to be one of my favourite because they can offer a greater range of pistonic operation than soft cones, but without the headache of metal cones.
1) Stiff, rigid cones that resonate and ring at a specific frequency and require an xover of at least 1/3 this frequency to work at their best. This includes diamond, all metals and ceramics.
2) Soft, well controlled, well damped cones that do not display the characteristic distortion amplification due to cone resonance of the rigid cones. This means drivers like scan speaks revelator slit paper series, scan speaks fibre glass cones, vifa's TC9, the Satori from SB acoustics, many poly cones etc.
3) Then this group, the composite materials, some weaves/adhesive blends, laminate cones, kevlar, carbon fibre and some paper blends. Anything really that is reasonably stiff but that also posses some decent internal damping. These tend to display ugly resonances, like the metal cones, but at lower frequencies than metal cones. The main difference here is that these cones tend not to amplify the distortion products. You may think this an advantage and it is, but because the resonances usually occur quite a bit lower than metal cones, they can interfere with where you'd want the driver to normally operate. If the driver is well designed it is still usable, but not as flexible as the soft cone and can usually be crossed a bit higher than the metal cone.
Composites tend to be one of my favourite because they can offer a greater range of pistonic operation than soft cones, but without the headache of metal cones.
I think you have to define what you mean by 'ring' then. Any resonance could be classified as the driver 'ringing' and any 'peak' in the frequency response, no matter how small could also be classified as the cone 'ringing'. Yet I wouldn't describe a well damped poly cone as something that 'rings'.
Not at least something like this.
http://www.tymphany.com/files/HDS-P830874 Rev1_0.pdf
Not at least something like this.
http://www.tymphany.com/files/HDS-P830874 Rev1_0.pdf
Peaks and nulls in FR should not be considered ringing.
Ringing is long decay in the Impulse Response at various frequencies.
Yes, they all decay, when you want to define it as ringing is up to you, some ringing may even desired if you are inclined that way.
The attack, decay, sustain and release of the impulse response along with the harmonic content and overtones will give the driver a unique tonal character.
How static or fluid the driver is is another high concern.
This all needs to be measured anechoically for accuracy.
IR and it's correlate ADSR are measured and presented on paper but the lines are never deciphered in my experience, the deciphering is unilaterally executed in the mind.
Flux density and volume shifting versus time are considerations as well.
Not sure why I'm writing all this.
Ringing is long decay in the Impulse Response at various frequencies.
Yes, they all decay, when you want to define it as ringing is up to you, some ringing may even desired if you are inclined that way.
The attack, decay, sustain and release of the impulse response along with the harmonic content and overtones will give the driver a unique tonal character.
How static or fluid the driver is is another high concern.
This all needs to be measured anechoically for accuracy.
IR and it's correlate ADSR are measured and presented on paper but the lines are never deciphered in my experience, the deciphering is unilaterally executed in the mind.
Flux density and volume shifting versus time are considerations as well.
Not sure why I'm writing all this.
You're saying a software FR equalizer will lessen or remove decay?
An equalizer will lower SPL / volume, less volume in the decay area will result in less decay.
A perfectly flat frequency response still has ringing, SPL and time are not related.
If you lessen the ringing with volume, the ADSR envelope will most likely still be the same, which is what gives paper and Titanium their tonal charaxter.
Aside from harmonic content, overtones and sensation of speed, perhaps,
An equalizer will lower SPL / volume, less volume in the decay area will result in less decay.
A perfectly flat frequency response still has ringing, SPL and time are not related.
If you lessen the ringing with volume, the ADSR envelope will most likely still be the same, which is what gives paper and Titanium their tonal charaxter.
Aside from harmonic content, overtones and sensation of speed, perhaps,
As far as I understand it if you equalise the FR so that the resonance is now flat then the decay time follows too. Like I said, you cannot do anything about harmonics exciting the resonance, but apart from that, for example if you're looking at a CSD diagram, if there's a ridge with a long decay time, if you EQ the FR flat, then the ridge will disappear completely.
A cone resonance, such as those in the SEAS drivers, are just regions where the driver is more efficient at converting energy. If a constant voltage is applied to the driver then a ridge appears at resonance because it is producing more sound energy during resonance than it is when it isn't. As there is more energy present it simply takes longer to dissipate hence the longer decay time.
A cone resonance, such as those in the SEAS drivers, are just regions where the driver is more efficient at converting energy. If a constant voltage is applied to the driver then a ridge appears at resonance because it is producing more sound energy during resonance than it is when it isn't. As there is more energy present it simply takes longer to dissipate hence the longer decay time.
Is this you just simply saying nope or do you have theoretical proof proving otherwise?
It's just that this goes against everything that I've ever read about CSD/FR plots and their relationship to one another.
It is true that you cannot linearise the non-linear part of the problem, such as the harmonic distortion exciting the resonances, but usually these are pretty low down in level that I cannot see them making much of a difference.
5th Element, I'm familiar with CSD and know the ridges you speak of.
If there's a ridge at 6 kHz and you adjust the equalizer to -24 dB SPL at 6 kHz then the ridge will disappear since all sonic content will disappear.
Aside from that, I don't see any relationship between SPL and TIME.
If the driver has decay, then the driver has decay.
If a church has decay due to echoic reflections them you call the Pope and say we need velvet curtains A-SAP.
If there's a ridge at 6 kHz and you adjust the equalizer to -24 dB SPL at 6 kHz then the ridge will disappear since all sonic content will disappear.
Aside from that, I don't see any relationship between SPL and TIME.
If the driver has decay, then the driver has decay.
If a church has decay due to echoic reflections them you call the Pope and say we need velvet curtains A-SAP.
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