Superscooper 18 Discussion/Scoop Design

bitzo wrote: Lev, I follow exatcly your advice. Not copyed the staip design.
I modeled each section in a dynamical way, like cubo12 script. So I can change depth, height, width, distance from baffle to rear baggle, baffle lenght, rearbaffle lenght, panel under baffle and it's angle, panel in front of the rear panel and and it's angle.
Dynamic script as well, hardcore trigonometry and I can customize regarding driver. And this is the sim, tbx100 loaded.

Well, that's a start.. smiley32
Getting that 103db point at 45hz would be next objective..
Please try modelling with PD1850/PD186..

post this params please Sd, Bl, Cms, Rms, fs, Le, Re

levyte357 wrote: match throat/compression ratio to driver,

thats the bit im on about from part a to b on pic, is this the bit that compresses and how do you work out the compresion ratio to driver.

bitzo wrote: post this params please Sd, Bl, Cms, Rms, fs, Le, Re

post script, would like to have a look at....... smiley17 i understand if youy dont want to, it takes hours to do complicated scrips with akabak.

bitzo wrote: post this params please Sd, Bl, Cms, Rms, fs, Le, Re

[attachment=0:x14c3fec]<!-- ia0 -->small_chmbr_drivers.jpg<!-- ia0 -->[/attachment:x14c3fec]

sorry but le is not listed...

bee wrote:

levyte357 wrote: match throat/compression ratio to driver,

thats the bit im on about from part a to b on pic, is this the bit that compresses and how do you work out the compresion ratio to driver.

There is a formula for this, but how well it works regarding scoops is a different question..

Maybe EBP or qts is a guide, but then PD186 and Fane 18XB break these rules.. smiley29

bitzo wrote: sorry but le is not listed...

For some reason in my HR data I have

PD1850 Le = 2.50
PD186 Le = 2.49

This are two hypothetical variations of "same" scoop cabinet. (same cahmber/throat/mouth)

"A" version is 18" derivative from JBL 4520 layout; ASS style, reflection type fold (bit with negative "expansion" @ LEV smiley2 ) , overall slower expansion rate (in theory better suit for deeper bass)

"B" is 18" derivative from JBL 4530 layout; "purist" style, proper constant expansion, ~constant/expanding area fold, overall higher expansion rate (here theory suggests bit higher SPL and a bit more usable bandwidth)




I have not built any of those (friend of mine have two version "B" and he is more than happy .. but unfortunately have nothing to compare with.. soooo do not ask me)

levyte357 wrote: Well, that's a start.. smiley32
Getting that 103db point at 45hz would be next objective..
Please try modelling with PD1850/PD186..

done with pd1850 but pretty deeper.


Imho, the A version is so much solid then B version, only in the modded section for sure. The experiment could be obtain the same "solidity" with pure expansion. So.... we can find if this is an expansion issue or a construction one.