loud.. the missing equation?

[Etac 10+ year member]

ok, i know xmax, cone area ect.. have a role in how "loud" a speaker is... but waht am i missing? take the btl for example doesnt it have something like 14 mm xmax (didnt look it up going by memory) yet is an spl monster... so what is it that makes it so loud.. bl? moving mass? something else?

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[Trey803 5,000+ posts]

if you mean db's it is all about moving the air which is work done by the cone converting electrical energy into an alternate form of energy ie sound waves. The efficiency of this conversion will dictate spl

 

[azbass 5,000+ posts]

14mm xmax lol

 

[Trey803 5,000+ posts]

the perceived loudness can be changed by alternate positing of the sound waves coming from your speaker. When these reflect off interior walls the sound can have an amplification effect.....or even cancellation effect

 

[Etac 10+ year member]

14mm xmax lol

ok i looked it up, its 16mm, sorry i guess that 2mm is the difference maker? lol

 

[azbass 5,000+ posts]

16?

 

[Etac 10+ year member]

https://ssl.perfora.net/www.ficaraudio.com/sess/utn;jsessionid=1548e2dcb7b4af5/shopdata/0050_Speakers/0010_BTL/product_overview.shopscript

check for yourself

 

[Immacomputer 10+ year member]

Loud is all about effectively coupling a speaker to an enclosure and coupling that system to a vehicle's environment. Some speakers are naturally able to be coupled well with certain enclosure types. Many SPL subs work very well with ported enclosures and can help drive a system into resonance with great efficiency. If you have coupled the sub and enclosure well, coupling to the interior is what makes or breaks getting loud. That's why sometimes nice equipment doesn't do well and other times it does and vice versa.

Also, SPL subs are able to handle loads of power without going into power compression which means more current which leads to a stronger EMF which is more acceleration which will directly be related to output.

Oh, and Xmax is not a figure to really focus on when worrying about how loud something will be. It's not good to look at one or two parameters and leave everything else aside. All factors need to come into play (all T/S parameters, enclosure, and environment) to get an idea of how well a system will work. Xmax is also only a measurement of the linear throw of the driver. Nonlinear does not mean the sub will be moving side to side; nonlinear is based around the flux density of the magnetic field of the motor. When the EMF changes over distance of the coil travel too much, the driver is operating in non linear region and many parameters of the sub will shift as it moves in an out (great way to get distortion).

 

[azbass 5,000+ posts]

maybe im looking at another woofer, but 16mm for that kinda woofer? humph

 

[SSS 18734 5,000+ posts]

it doesn't take high excursion to get loud. The box and the motor are going to dictate that in a SPL setup, especially near tuning.

SPL drivers typically have lower xmax ratings than their SQ counterparts.