jbl 2235 design help

[slider908]

hi
i recently purchased 2 jbl 2235h and need help designing a box for they i plan on making 2 identical boxes.

first of all i notice the qts is 0.25 why is this weren't they designed as a sealed system woofer.

i want a sealed box that gives be the most extension but isn't underdamped is this possibe so the system Q is over 0.55. what is a good value for hi-fi usage. is there anyway of enlarging a cabinet enclosure. (you can downsize but stuffing it)

also i have a pair of me-120 woofers the ones from the K2-5800. can any one estimate the T/s parameters from the me-150. it appears jbl didn't do full T/S parameter run as they wern't intended for mass usage
what would be and ideal box for them as well.

do any of you know where i can purchase a 15hz high pass infrasonic filter or get custom made crossovers or a place with a bigger selection than partsexpress. if not where can i learn to start building them even though i prefer not to?

all posts are welcomed i need all the help i can get so please post

thanks for all the help,
john

 

[gonefishin]

slider...no experience with the 2235 myself...but Mike Bates over at AA has some experience owning and building with this woofer. My want to give him a try?



good luck!

 

[Robh3606]

Go to the Lansing Site

www.audioheritage.org

and do a search in the forum. There is lots of information for building boxes and tunning for this woofer.

Rob2

 

[mikee.e]

im using winisd pros jbl2235 ,proly correct specs.

DO NOT use sealed box unless you want tiny output!however it would sound nice...until you turn it up for reference high SPL and it may distort due to being many db down at 40hz...

Woofer EBP
Fs/Qes=71.9.well into ported box range.

-3db @70hz sealed box.

150L tuned to 31hz
or
200L tuned to 25

id go 150L tuned to 31hz,then you have nice efficiency!

my jbl2226h is tuned to 33hz,175L its down from its 97db efficiency,(runs of 10watts til i get 240watt)loudly!

where i can purchase a 15hz high pass infrasonic filter or get custom made crossovers or a place with a bigger selection than partsexpress.

im sure theres MANY electronics kit places u can get subsonic filters! i live in NZ and i can order one from Jaycar.co.nz i think....

a subsonic filter is just a high pass 12db/octave or 24db.octave .

http://www.sound.westhost.com/
Try there! u can order PCBS off him i think..quality stuff i reckon)not that i have any(

Cheers!

 

[mikee.e]

all those box sizes are for ONE woofer..i dont complicate things by using 2 woofers (and then forgetting haha) and i prefer 2 seperate 200L boxes than one 400!

cheers

 

[mikee.e]

and Group delay,forgot it! its supposed to be in the little square of blank space in the pic above

the low tuned one ofcourse has less GD in normal musical frequencies..making it sound more closer to sealed box quality

 

[slider908]

thanks for all the suggestions mikee i will take those into consideration