Hello again, I was wondering if someone had a link that would help me find out the amount of cone extention I will be placing on my four inch mids at a cross frequency of 300hz. I am using the Peerless four inch mid/woofer HDS PPB. Is there a simple formula for fig. for this? I am using two and wiring in parallel so my rotel anp will see about a four ohm load. The driver I am using says it has a linear excursion of +or- three mm, thats about all the info I can find on this driver on this parameter.
I'm sure this is dependant on volume level, I do listen to movies at reference levels, and like my music pretty much the same. Crossover is 24db per and electronic.
Thanks,
dallaire

Thanks,
dallaire
Yes, the RMS cone amplitude for a given sound pressure p in free space is
x=p*4*pi*r/(Sd*w²*rho0)
r is the distance at which p is measured, w=2*pi*f, rho0=1.2 kg/m³
p can be derived from sound pressure level as p=pref*10^(Lp/20)
where pref=20 µPa, Lp is the sound pressure level in dB.
So, for example, if the Lp=94 dB, r=1 m, f=300 Hz and Sd=100 cm², then
p=2e-5*10^(94/20)=1 Pa
x=1*4*pi*1/(0.01*(2*pi*300)²*1.2)=0.294 mm
x=p*4*pi*r/(Sd*w²*rho0)
r is the distance at which p is measured, w=2*pi*f, rho0=1.2 kg/m³
p can be derived from sound pressure level as p=pref*10^(Lp/20)
where pref=20 µPa, Lp is the sound pressure level in dB.
So, for example, if the Lp=94 dB, r=1 m, f=300 Hz and Sd=100 cm², then
p=2e-5*10^(94/20)=1 Pa
x=1*4*pi*1/(0.01*(2*pi*300)²*1.2)=0.294 mm
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.