Can anyone tell me how subwoofers work? Like I know all their parts and how they work etc… basically….but the only thing I can’t get my head around is this. I know there’s a lot of factors like T/S parameters, box, room etc… involved BUT so many people are telling me that to get loud is “mostly” the factors of sd and xmax correct? You have a specific sd of a speaker and to get louder you feed it more power causing the speaker to move more for more displacement OR you have a speaker running at say 1inch peak to peak and to get lounder you can increase the sd BUT here’s the thing if it’s all about “displacement” is which some people tell me then why is a $2000 SPL sub way way louder than a generic cheap $200 sub…them both having the same sd and xmax thus having the same displacement. I know people are saying well you feed the SPL sub 5000Wrms and the cheap sub 300wrms….but I’m thinking how does that extra energy from the SPL sub convert into audio being having the same displacement?
Dam confused here hahaha 😕
Cheers guys
Dam confused here hahaha 😕
Cheers guys
a lot of it has to do with manufacturers measuring xmax differently.
Voice Coil Length - Height of the Magnetic Gap) / 2
70% bl
maybe more that I don't know about...
there is also mechanical excursion limits. xmax, for oversimplification because I don't feel like moving to a keyboard from my phone, is the maximum LINEAR excursion. there is an xmech that some manufacturers quote, especially the spl oriented ones, that now comes into play. which is how far the woofer can actually travel before bottoming out.
this is just one of the reasons.
wattage is also usually also a thermal rating not a rating before the vc bottoms out.
You should download winisd and add your favorite drivers to it and compare the outputs at different frequencies in different enclosures I think you would learn a lot from that.
Voice Coil Length - Height of the Magnetic Gap) / 2
70% bl
maybe more that I don't know about...
there is also mechanical excursion limits. xmax, for oversimplification because I don't feel like moving to a keyboard from my phone, is the maximum LINEAR excursion. there is an xmech that some manufacturers quote, especially the spl oriented ones, that now comes into play. which is how far the woofer can actually travel before bottoming out.
this is just one of the reasons.
wattage is also usually also a thermal rating not a rating before the vc bottoms out.
You should download winisd and add your favorite drivers to it and compare the outputs at different frequencies in different enclosures I think you would learn a lot from that.
@skydeaner thankyou for your reply I'm always keen to learn more!!! I do have that program haha haven’t used it for ages.
I’m just so curious as I see a lot of systems that are loud but lack sd and xmax then you have systems that have long throw subs with more sd that are nowhere near as loud, I know it’s all about the box, the room and the T/S parameters, etc…. hitting the sweet spot but surely the movement and sd plays a massive part in the situation??
I see loud drivers with small xmax like as much as a PA driver which is very small compared to some other drivers that can move inches and still be with in their parameters but not be as loud.
I was originally thinking the cone was like throwing a foam ball vs a lead ball, both moving the same distance and both having the same velocity but obviously the lead ball will have a ton more kinetic energy stored in it verses the foam ball thus the lead ball will inflict more damage when hitting something, like the cone has more energy to transfer it into sound waves somehow maybe …… BUT I think my theory is incorrect haha
I’m just so curious as I see a lot of systems that are loud but lack sd and xmax then you have systems that have long throw subs with more sd that are nowhere near as loud, I know it’s all about the box, the room and the T/S parameters, etc…. hitting the sweet spot but surely the movement and sd plays a massive part in the situation??
I see loud drivers with small xmax like as much as a PA driver which is very small compared to some other drivers that can move inches and still be with in their parameters but not be as loud.
I was originally thinking the cone was like throwing a foam ball vs a lead ball, both moving the same distance and both having the same velocity but obviously the lead ball will have a ton more kinetic energy stored in it verses the foam ball thus the lead ball will inflict more damage when hitting something, like the cone has more energy to transfer it into sound waves somehow maybe …… BUT I think my theory is incorrect haha
those PA drivers will not Play as deep.
seriously check out the xmax graphs for different power loads in win isd again.
I see what you are thinking. and someone correct me if I'm wrong but any given transducer with the same sd with the cone moving the same amount of air is going to have the same output potential. like you said box design plays a huge role too though. differing amounts of moving mass aren't going to effect anything except efficiency I think.
The big thing is lower program watt drivers will meet their thermal limits at higher frequency long before they reach xmech.
That 5000 watt driver may have the exact same output at 20hz as the 300 watt driver as it will be excursion limited long before it gets to 5000 watts. But at 45-50 hz the 300 watt coil will burn up even if the driver is only sweeping 5mm worth of air if you throw 1000w on it. and the 5000w woofer will be able to reach its excursion limit at that higher frequency because it has the power handling to do it.
every halving of frequency requires double the excursion roughly to reproduce the sound.
again these are super over simplifications as excursion is also completely dependent on enclosure and if in a vented enclosure the cone will move the least at tuning frequency and had a steep steep increase in move t at any frequency below. And the extra sound you are not seeing from the cone movement comes from the port and enclosure itself due to the box being a helmholtz resonator.
that's a fun Google lemme tell ya.
seriously check out the xmax graphs for different power loads in win isd again.
I see what you are thinking. and someone correct me if I'm wrong but any given transducer with the same sd with the cone moving the same amount of air is going to have the same output potential. like you said box design plays a huge role too though. differing amounts of moving mass aren't going to effect anything except efficiency I think.
The big thing is lower program watt drivers will meet their thermal limits at higher frequency long before they reach xmech.
That 5000 watt driver may have the exact same output at 20hz as the 300 watt driver as it will be excursion limited long before it gets to 5000 watts. But at 45-50 hz the 300 watt coil will burn up even if the driver is only sweeping 5mm worth of air if you throw 1000w on it. and the 5000w woofer will be able to reach its excursion limit at that higher frequency because it has the power handling to do it.
every halving of frequency requires double the excursion roughly to reproduce the sound.
again these are super over simplifications as excursion is also completely dependent on enclosure and if in a vented enclosure the cone will move the least at tuning frequency and had a steep steep increase in move t at any frequency below. And the extra sound you are not seeing from the cone movement comes from the port and enclosure itself due to the box being a helmholtz resonator.
that's a fun Google lemme tell ya.