Fostex Horn - TB Drivers ??

[mjq]

I have a pair of Fostex FE103 back horns with blown drivers, and a pair of Tangband W4-656S drivers.
I'm trying to figure out if these horns can be made to work for the W4-656 drivers...

FE103 / W4-656S
---------------------
Qts - 0.36 / 0.35
Vas (L) - 6.9 / 5.2
Fs - 79.5 / 65.0
Xmax (mm) - 0.3 / 3.0
Qms - 2.87 / 2.08
Qes - 0.40 / 0.42
SPL - 89 / 87
BL - 4.42 / 5.40

It looks like the specs are reasonable close with the Vas being the biggest difference (I think) as far as horn loading is concerned...
Is it be possible to change the back chamber for the horn to tune it to the Tangband ??
and if so, how ??

Thanks,
Jason

 

[RAW]

http://audio-resolution.com/zhorn/
Check out Toms web site.He uses thew4-657s .
Email him he will answer questions.