same excursion rate but louder??

[Hayden]

How can this be? I have a good 12” sub comparing it to say an mtx thunder 9500 or similar hi end sub. Forget the wattage at the moment if I crank my 12” to say 1 inch peak to peak and crank the 9500 to the same excursion rate why is the 9500 massively louder? What am I missing here? Is it because it has the physical power to push the cone? I know the wattage matters too but it’s something to do with the technical data I don’t understand.
If any one could help.
Thanks

[richie00boy]

Wattage is irrelevant, all that matters is the excursion and cone area. It's just that some speakers will requires more or less watts for the same movement. If you are testing with a sine wave of single frequency there should not be any difference if the speakers are similar cone area and moving the same.

If you are testing with music and determining excursion by eye, there is your problem.

[Hayden]

I still don’t understand there must be other explanation. I have a 12” running right now that has more xmax and the same cone area of the digital design sub 10” which scored 169db alone but no way is it louder? I understand about cone area. If Wattage is irrelevant why do db drag competitors have thousands and thousands of watts going?

[djQUAN]

bear in mind the enclosure type also plays a big part.

if your 12" is in a sealed box and the 10" in a ported box. then there's no contest.

another is how well the enclosure is implemented. a good subwoofer in an enclosure design that is not suited for this driver will make it sound like crap. while a budget sub in a well designed box will outperform most off the shelf subs.

[Toast_Master]

From what I gather they have thousounds of watts going because High excersion woofers are usually unsensitive and need extra power to get to the same exercion as a lower excursion woofer with a higher sensivity

and

normally spl subs are crossed over high and tuned high so no harmful uneeded spl-less low frequency gets through, so all the power is used on a frequency that is easy to make loud like 40 Hz and up

also 10 Hz going 1" excursion will sound and basiclly produce nothing in spl terms, but say 50 Hz going 1" excursion and whoa, youll have bloody loud boomy bass,

lol I know most of you know that, but this is my first input to a info post

[badman]

If you're just judging visually, you're not really being accurate. Test tones and measurement are the only way to accurately judge if you're really getting more SPL from equivalent excursion. And if you are, then the louder driver is distorting more, the distortion components don't require nearly so much excursion to achieve higher SPLs as they're greater in frequency and require less displacement accordingly.

[Rademakers]

Sensitivity on the louder driver might just be higher.

Wkr Johan

[richie00boy]

Sensitivity is just a measure of electrical input vs SPL output. If two cones of identical area are moving the same distance in the same kind of box, then even if the difference in sensitivty between them is 10dB, in the bass end the sound will be the same for a specific low frequency, it's just that one will require much less power.

As I said before, are you testing with music or sine wave, and how are you determining excursion? These are vitally important.

[Rademakers]

I don't think you have enough information to rule out a difference based upon sensitivity or not

Wkr Johan

[hifiger]

Originally posted by richie00boy
Sensitivity is just a measure of electrical input vs SPL output. If two cones of identical area are moving the same distance in the same kind of box, then even if the difference in sensitivty between them is 10dB, in the bass end the sound will be the same for a specific low frequency, it's just that one will require much less power.

This is True.
The sensitiviy only shows how much power is needed to reach a given spl at a certain frequency.
If the speakers are being measured by xmax with sine waves, then the only thing that would chance the percived spl would be distortion, which many people associate with bass.
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