Regarding the topic, there are three parameters that go hand by hand, those are Qts, Fs and Mms.
First regarding Qts vs Qts alone (would rather say Qes and BL but let's stay on topic), there should be no difference in the playing bands of the respective drivers. Especially in the piston action region, a driver playing in a properly aligned enclosure should make no difference with another driver with the same alignment.
This is provided that all drivers are crossed over before the end of their normal operating range.
But regarding the woofer in a two way system, the stronger motor will provide better sound as it will have better midrange and impulse performance.
The penalty in the low frequencies is remedied with low Fs and big moving mass. In this case Qms participates as the balancing parameter for Qes and BL thus forming useable Qts parameter. It is quite often to have Qms of 12 or even more in a strong motor PA driver, this provided that I personally am not capable to distinguish Qms 3.5 from 13.5 is a clear telltale.
It is completely possible for a 0.24 Qts 25 Hz Fs driver to achieve F3 of 24 Hz provided that it is 8 inches and it has the appropriate Fs and moving mass...
For me the other sure sign for balanced parameters is the sensitivity provided that Xmax is within normal (not too big), 89 to 93 db/w would mean that tel low Qts driver has an appropriately heavy cone and low Fs thus it will extend low and will be "fast" at high frequencies.
The "speed" at high frequencies is entirely cone dependant and here I will disagree with the light rigid cone concept. Even diamond and titanium cones have breach up frequencies.
I would rather relay on a thicker and heavier cone exhibiting gradual breackup thus improving BL vs Mms ratio with frequency.
My 5 cents.
Best Regards!
First regarding Qts vs Qts alone (would rather say Qes and BL but let's stay on topic), there should be no difference in the playing bands of the respective drivers. Especially in the piston action region, a driver playing in a properly aligned enclosure should make no difference with another driver with the same alignment.
This is provided that all drivers are crossed over before the end of their normal operating range.
But regarding the woofer in a two way system, the stronger motor will provide better sound as it will have better midrange and impulse performance.
The penalty in the low frequencies is remedied with low Fs and big moving mass. In this case Qms participates as the balancing parameter for Qes and BL thus forming useable Qts parameter. It is quite often to have Qms of 12 or even more in a strong motor PA driver, this provided that I personally am not capable to distinguish Qms 3.5 from 13.5 is a clear telltale.
It is completely possible for a 0.24 Qts 25 Hz Fs driver to achieve F3 of 24 Hz provided that it is 8 inches and it has the appropriate Fs and moving mass...
For me the other sure sign for balanced parameters is the sensitivity provided that Xmax is within normal (not too big), 89 to 93 db/w would mean that tel low Qts driver has an appropriately heavy cone and low Fs thus it will extend low and will be "fast" at high frequencies.
The "speed" at high frequencies is entirely cone dependant and here I will disagree with the light rigid cone concept. Even diamond and titanium cones have breach up frequencies.
I would rather relay on a thicker and heavier cone exhibiting gradual breackup thus improving BL vs Mms ratio with frequency.
My 5 cents.
Best Regards!
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Yes, the low tuning frequency pushes all port induced artefacts lower where their magnitude becomes irrelevant while leaving the useable frequencies with minimum group delay and flat impedance response.
Speaking of tuning frequency, one advantage and one disadvantage of low Q drivers come to mind.
It is advantageous to work with low Qts driver and vented enclosure since the required port length for the same frequency will be relatively shorter than the one of a system utilising higher Qts driver. Hence much lower maximal and overal group delay. (for instance port d 75 mm by 25mm long can give Fb 20-25 Hz in a >100L system with Qts 0.22 fs 23 Hz 12 inch driver)
The disadvantage is that lower Qts drivers exhibit much higher impedance peaks at resonance, at Fc for sealed enclosures and below and above Fb for bass reflex enclosures.
Speaking of tuning frequency, one advantage and one disadvantage of low Q drivers come to mind.
It is advantageous to work with low Qts driver and vented enclosure since the required port length for the same frequency will be relatively shorter than the one of a system utilising higher Qts driver. Hence much lower maximal and overal group delay. (for instance port d 75 mm by 25mm long can give Fb 20-25 Hz in a >100L system with Qts 0.22 fs 23 Hz 12 inch driver)
The disadvantage is that lower Qts drivers exhibit much higher impedance peaks at resonance, at Fc for sealed enclosures and below and above Fb for bass reflex enclosures.
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