cotjones
10+ year member
CarAudio.com Veteran
well i feel like i'm not giving you enough credit for your arguement because are partially right about some things, but you are completely missing the point you are agrueing about something completely different than i am... your argueing about how a longer excursion helps the sub be linear and you are right about that.... but your not paying attention to a couple of facts...
first of all distortion allways exists unless you are in a vacume with all perfect equiptment and no interference of any kind... lower amplication only makes it less audible just as it makes the music less audible... but it's still there....
second (this is a important one)... A VOICE COIL'S ABILITY TO CHANGE ITS CURRENT GETS FASTER AS THE POWER INCREASES... i don't understand how someone who is apperantly so knowledgeable about audio doesn't see this
here's where your point comes in.... as the power increases the sub also gets less linear because in effect every time the sub reaches it's "resting point" it is, in effect, thrown to its excursion point in this part of the phase as the sub goes further and further out from the center the coil loses more and more control makeing it less accurate... the fact is that the 13w7 has the ability to hit full excursion and still sound somewhat decent and have an on the map SQ reading
but as you decrease power transient responce gets better untill you get to 1000watts where sq decreases not having anything to do with to do with excursion or hom the suspension is designed but because the speaker requires a specific amount of power to reach maximum sq now
now a point that you haven't said but i believe you might understand is that the reason sound quality usually doesn't decrease at lower levels is because... as the coil's ability to contribute its "current magnitude-forced transient responce" decreases, motor gains control raising the transient response. but underpowering is different than turning the volume down... jl amps are recommended to put out a specific output voltage and the subs are designed to recieve a certain voltage... this amount of voltage is regulated by the amp to make the change in volume by the source... to not interfere with sound quality and to give a balance of sound(so the volume of the substage increases and decreases at a comparable level to the frontstage) but all of this is set from a reference level predeterimined by the amp input, amp output, sub resistances, sub efficiency, and many other factors, but subs aren't as flexible in application as most people believe.
(((((PAY CLOSE ATTENTION TO THIS PART...))))) a 500/1 will never be able to power a 13w7 and give a flat responce because for you to reach half of the subs input/output potential you must set the amp to full gain... with that said an amplifier works exponentialy multiplying the signal input,
quote edit: i know that is not exactly how it works, it acutually doesn't change how much the amp is amplifying but only how powerfull the input is... but the effect is still the same
heres an example: lets say you want a 13w7 to run at 250 watts at maxium potential this will give you horrible sound quality with a 250/1 because gain is set on maximum... but possibly good sound quality with a 1000/1 set to a level of 25% which should give you about that 250 watts you were lookin for but there is another problem... 25 percent of your system's volume is reaching your "maximum sub potential of 250 watts... solution? smaller substage.... your front stage should be able to keep up with your subs maximum potential at all times, other wise you are forced to underpower your subs... or use some kind of attenuatore on the input of a lager amp to retain the same quality at a lower level... you simply can't underpower your subs (!!!!!!you HAVE to have a amp powerfull enough for at least IDEAL output inorder to retain sound quality at lower levels!!!!!) i say again you can't underpower your subs and get good sound quality!! some of those people who have big subs in their car have big subs that handle less power or they have BIG powerfull amps the fact is ....
the fact is that 2 amps pushing the same power one at 25% one at 100% will not produce the same quality... so yes! the 13W7 REQUIRES 1000watts to have the best sound quality at all volume levels ... if the 13w7 is too loud for your SQ if you want to run 500 watts get the 10 or a lesser series you just can't underpower a sub and get good quality
first of all distortion allways exists unless you are in a vacume with all perfect equiptment and no interference of any kind... lower amplication only makes it less audible just as it makes the music less audible... but it's still there....
second (this is a important one)... A VOICE COIL'S ABILITY TO CHANGE ITS CURRENT GETS FASTER AS THE POWER INCREASES... i don't understand how someone who is apperantly so knowledgeable about audio doesn't see this
here's where your point comes in.... as the power increases the sub also gets less linear because in effect every time the sub reaches it's "resting point" it is, in effect, thrown to its excursion point in this part of the phase as the sub goes further and further out from the center the coil loses more and more control makeing it less accurate... the fact is that the 13w7 has the ability to hit full excursion and still sound somewhat decent and have an on the map SQ reading
but as you decrease power transient responce gets better untill you get to 1000watts where sq decreases not having anything to do with to do with excursion or hom the suspension is designed but because the speaker requires a specific amount of power to reach maximum sq now
now a point that you haven't said but i believe you might understand is that the reason sound quality usually doesn't decrease at lower levels is because... as the coil's ability to contribute its "current magnitude-forced transient responce" decreases, motor gains control raising the transient response. but underpowering is different than turning the volume down... jl amps are recommended to put out a specific output voltage and the subs are designed to recieve a certain voltage... this amount of voltage is regulated by the amp to make the change in volume by the source... to not interfere with sound quality and to give a balance of sound(so the volume of the substage increases and decreases at a comparable level to the frontstage) but all of this is set from a reference level predeterimined by the amp input, amp output, sub resistances, sub efficiency, and many other factors, but subs aren't as flexible in application as most people believe.
(((((PAY CLOSE ATTENTION TO THIS PART...))))) a 500/1 will never be able to power a 13w7 and give a flat responce because for you to reach half of the subs input/output potential you must set the amp to full gain... with that said an amplifier works exponentialy multiplying the signal input,
so a sub that is useing half of its potential but the full potential of the amp will have far more noticeable distortion because if the distortion is at a higher amplitude than the music input, which it almost allways is, the distortion will be amplified more than the music is....turning the gain up raises how much the input is muliplied...
quote edit: i know that is not exactly how it works, it acutually doesn't change how much the amp is amplifying but only how powerfull the input is... but the effect is still the same
heres an example: lets say you want a 13w7 to run at 250 watts at maxium potential this will give you horrible sound quality with a 250/1 because gain is set on maximum... but possibly good sound quality with a 1000/1 set to a level of 25% which should give you about that 250 watts you were lookin for but there is another problem... 25 percent of your system's volume is reaching your "maximum sub potential of 250 watts... solution? smaller substage.... your front stage should be able to keep up with your subs maximum potential at all times, other wise you are forced to underpower your subs... or use some kind of attenuatore on the input of a lager amp to retain the same quality at a lower level... you simply can't underpower your subs (!!!!!!you HAVE to have a amp powerfull enough for at least IDEAL output inorder to retain sound quality at lower levels!!!!!) i say again you can't underpower your subs and get good sound quality!! some of those people who have big subs in their car have big subs that handle less power or they have BIG powerfull amps the fact is ....
the fact is that 2 amps pushing the same power one at 25% one at 100% will not produce the same quality... so yes! the 13W7 REQUIRES 1000watts to have the best sound quality at all volume levels ... if the 13w7 is too loud for your SQ if you want to run 500 watts get the 10 or a lesser series you just can't underpower a sub and get good quality
