Spice speaker models

[vossie]

Hi,

Could you guys please explain to me how to create a spice model for a speaker driver?

R3 is the measured DC impedance of the coil. L2 is the measured coil inductance. C2, L3 and R4 is the problem.

...or am I missing it more than I think?

Please help.😕

 

[mr_push_pull]

Funny you should ask, because I was going to post the exact same question before I saw yours.
What I've found in my researches:
http://www.silcom.com/~aludwig/Sysdes/Thiel_small_analysis.htm

Lces = (Bl^2) * Cms
Res = (Bl^2) / Rms
Cms = Mms / (Bl^2)

Now, what I don't know is how to compute Cms, Rms and Mms from Qms, Qes, Sd, Vas and Fs. For now I'm using BassBox to compute them for me (it has that "Compute All" button), but some formulas would be nice. I wasn't able to find something usable on the web.

 

[mr_push_pull]

Also, check out this page http://users.ece.gatech.edu/~mleach/

In this paper at page 4 is the equivalent transfer function of a loadspeaker.

And finally the exact formulas we were looking for:

Res = Qms / Qes * Re
Lces = Re / (2 * pi * Fs * Qes)
Cmes = Qes / (2 * pi * Fs * Re)

 

[vossie]

Thanks Mr_push_pull - I'm still digesting all of this.

 

[Konrad]

http://www.mainz.ac.nz/loudspeakerdesign/eqcircuit.html#
http://www.egbeck.de/mass3.htm
http://users.ece.gatech.edu/~mleach/papers/vcinduc.pdf

I recomend som searces like:
MEMS Technology Using an Accelerometer to Make an Active Subwoofer_files
Classical Feedback Control.htm

And other like here in forum with MFB and servo sub

 

[vossie]

Thanks a lot guys, this helps much!🙂

 

[Konrad]

Well i found this , and so far as i've seen it seems GOOD! : http://www.arcavia.com/kyle/Equations/index.html

 

[catapult]

Here's one more from Seigfeid Linkwitz's site.

http://www.linkwitzlab.com/thor-design.htm