how do you know your pushing your subs to the limits? I remember thrashing my W3, but there werent any signs of smoke, funky noises from sub or a distorted sound..

so what are the signs?

You can usually hear the bass sounding a bit different to normal, slightly strained perhaps. Although most of the time unless you're overpowering the sub by a fair bit or haven't got a subsonic filter then it's more likely to be the amp distorting, especially with impedance rise meaning your amp is doing 200W instead of 500W! For example with my sub (Cerwin Vega Vega124) at it's rated power in the recommended box with plenty of port area the sub only just exceeds half of its peak to peak excursion limit (21mm excursion from a sub capacble of 19mm one way (38mm p2p).

Hmmmm what if its due to the headunit? I remember my line driver indicating a clipped signal at -6DB when volume was 'pushed' hard...

Im sure its from the HU, the only way i suppose you could measure the amp clipping is with an scope right?

They make a horrible noise when they hit the bumop stops LOL

Ben

you can tell - there is a difference in tone.

still tryna find the limits of my sub! il tell you when i've found em! :p

They make a horrible noise when they hit the bumop stops LOL

Ben
Hehe its a wonderful noise :clown: EddyPs XXX I think it was, free air, ******** the bump stops, moo ha ha

The smell of burning VCs is quite a nice one too

M:B

There are 2 methods of comprehensively destroying a sub, by reaching it's thermal limits, or mechanical limits...

Thermal limits, mean your pushing too power through the sub, causing the voice coils to heat up... only a certain percentage of power throw through a speaker is converted to sound, a good chunk of it is converted to heat, a byproducts related to efficiency. A speakers design aids the dissipation of heat, by having the motion apply a cooling factor to the VCs. If more power is pushed through the sub, and more heat created than the design can dissipate, the coils will get hotter and hotter, often causing the glue on the former to heat up, giving that distinclive smell ;)

Further abuse will eventually reach a point where voice coils are irrecoverably damaged, making the sub unusable


A sub can also be destroyed by reaching mechanical limits, and a sub surpassing the limits of its suspension, causing damage to the surround, having the VC former bouncing off the backplate, or tearing a spider. Mechanical limits are very much dependant on box design... very large ported designs offer less air support, causing a sub to over-excurt at a lower supplied power than for example, a small sealed box.

Over-excursion is even more of a consideration in some modern subs, such as the Orion HCCA2, where in the right box, thermal limits surpass physical limits

It's worth noticing that, in nearly all circumstances you will hear audible distortion before you reach either physical or thermal limits of a driver

Blade you really are a on fact-giving mission these last few days! I like it a lot :)

M:B

Clack, clack, clack.....:D

Blade you really are a on fact-giving mission these last few days! I like it a lot :)

M:B

It's just nice to have a proper SPL/Streetbass forum to put this stuff :)

You reputation whore Rich!!!!

My W3 makes a nasty noise if you turn it up too loud whilst it bounces off the backplate :twisted:

I just found that both subs I killed kicked up a hell of a stink before all the sound output stopped completely. At the time I thought I'd picked up a carrier bag or something on the engine blook and the smell was coming from outside the car via the blowers. The second one started to smell and I just though f*ck it and turned it up :)