Andrey B wrote:
weight x force = energy - it's simple physics
That's odd, never seen a sub woofer that moved the magnet.
I would look for sub woofers that have good peak-to-peak excursion, like my old boston acoustics, 2 inches peak to peak.
The further the speaker can move the more it can compress the air am i rite?
- Your not-so-local, untrained, uncertified, backyard mechanic. But my @!#$ runs
and what pushes the cone?
Andrey B wrote:and what pushes the cone?
A motor.
Ok here goes.
The magnet holds a certain amount of potential energy in the form of magnetic charge.
A power amplifier uses power from the battery and engine to amplify a small signal recieved from the source unit.
That power enters the conductor of the coil, inducing a magnetic charge. The amount of force the
motor can put out is completely dependent on both the magnet and the coil.
(People often put big magnets on shitty speaker to make them look better, when the coil can't handle the amount of potential the magnet can complement.)
The impedance of the coil, the quality of the copper, the cooling mechanisms (to keep impedance low), the compliance of the surround the compliance of the spider, the size of the coil, the SHAPE of the cone (imagine sticking your arm out the window of a moving car and comparing how a cupped hand interacts with moving air vs a flat hand.) the rigidity of the cone, the weight of the cone, the size of the cone.
Do I have to go on?
bradsk88 wrote:
That power enters the conductor of the coil, inducing a magnetic charge. The amount of force the motor can put out is completely dependent on both the magnet and the coil.
there you said it, and as we all know the bigger (therefore heavier) the magnet is the higher the electromagnetic charge is hence more force is induced by the motor
buddy, you completely missed the point of this thread
well obviously the coil has to be able to handle the power, duuhhh that's kind of a given )
let's take 2 subs for example
rf 3 that can handle 500 watts rms and say sundown sa12 that can also handle around the same amount of power
and feed them equally the same amount of power, around 500 watts
now the magnet on p3 weighs 20 lb (give or take) while SA's magnet weighs only about 12-15 lb
which COIL would be able to exert more power?
Andrey B wrote:buddy, you completely missed the point of this thread
well obviously the coil has to be able to handle the power, duuhhh that's kind of a given )
let's take 2 subs for example
rf 3 that can handle 500 watts rms and say sundown sa12 that can also handle around the same amount of power
and feed them equally the same amount of power, around 500 watts
now the magnet on p3 weighs 20 lb (give or take) while SA's magnet weighs only about 12-15 lb
which COIL would be able to exert more power?
The one with the bigger, better quality, better cooled coil.
You're throwing out the phrase "simple physics"
I'm sure then, that you understand that the magnet is
potential energy. And all it provides the "limit" of power that the motor can produce. The only reason the cone moves in the first place is because the coil is being charged and
pushing against the potential of the magnet.
If the magnet were creating the power, then explain to me why a subwoofer isn't always at 90º when the stereo is off.
And since I fear you don't understand what "90º" means.
i never denied the fact that the size/quality/cooling of the coil plays an important role in energy distribution from magnet ..
and like i said that's not even the point of this
say you have a 4 '' coil hyper cooled and made from polyimide which is being energized by a 2 lb magnet or
you have a 3'' coil naturally cooled, made from 1145 aluminum which is being pushed by a 20 lb magnet
which coil would produce a higher output given that both coils receive the same amount of power?
sorry, both magnets receive the same amount of 'potential energy'... not coils..
subwoofers do what they are told, they dont output anything without proper power and enclosure, end of story. you could have the greatest subwoofer ever made, and still only making wistle noises without the proper enclosure and the proper install.
an sa-12 weighs more then 20 lbs
if you want i can take a pic of the motor with the coil gap and awesome cooling...
click sig for my car audio videos
Anton Miller (PPC) wrote:subwoofers do what they are told, they dont output anything without proper power and enclosure, end of story. you could have the greatest subwoofer ever made, and still only making wistle noises without the proper enclosure and the proper install.
that's the man, couldn't agree with enclosure/install part more!
Andrey B wrote:i never denied the fact that the size/quality/cooling of the coil plays an important role in energy distribution from magnet ..
and like i said that's not even the point of this
say you have a 4 '' coil hyper cooled and made from polyimide which is being energized by a 2 lb magnet or
you have a 3'' coil naturally cooled, made from 1145 aluminum which is being pushed by a 20 lb magnet
which coil would produce a higher output given that both coils receive the same amount of power?
Alright. As long as you agree that big magnet does not necessarily mean better sub.
It's a difficult comparison to make, because two subs having different magnets but very similar coils almost never happens.
It's sort of like how a gas tank is chosen after a truck is designed, rather than a truck being designed around a gas tank. (Gas tank being the magnet in this case.)
Andrey B wrote:sorry, both magnets receive the same amount of 'potential energy'... not coils..
Splitting hairs here, but the coils recieve kinetic energy.
alright, fine , i guess you win here because i can't argue with the fact that kinetic > potential, after all a big chunk of potential energy is lost or emitted as heat anyways
but still you can't deny the fact the magnet size plays a big role too if you're looking for big power distribution and efficiency
a magnet size plays a role when paired with other componets. basing the quality of a speakers just based off of the weight is not smart at all is basically what were saying. as mentioned. lower quality companies place bigger magnets on subs. placed there componets in bigger amp heatsinks to make it look more powerful. i remember opening up one amp and finding the board and componets only took up half the amp shell. the other half was empty and just made to look like a big powerful am.
http://www.flickr.com/photos/sndsgood/ https://www.facebook.com/#!/Square1Photography
I still bet the Sundown's BL is greater than your P3's BL. There's a bunch of other factors (qts, qms, etc...) that even though the SA may have a smaller magnet, it's much more efficient and will have a flatter response and a better bandwidth than your P3.
