little guidance

I bought 4 of Apex jr's 6" Cerwin Vega speakers to build a set of M T M's. I was using Win ISD to design a box for them and I have been coming up with a really large enclosure design. It's calculating almost 10 cubic feet! I guess maybe I need some help using WinISD.

The only spec he has not provided is XMass so I just left it out. WinISD still calculated without it. Is that a critical measurment for this software to work?

Here are the specs he gives.

Cerwin-Vega 6" 16 ohm woofer good for MTM system $5.00ea.

Fs 58.48, Vas 20.05 l, Qts 0.8872, Qes 1.1012, Qms 4.5655, Re 14.88 ohms, Rm 0.739 ohms, Le 0.2540 mH, Spl 87.45 dB @ 1W/1M, cone area 0.0133m^2


Any help with a design would be appriciated. At $5 each I just coulden't resist. Maybe it was a bad choice of driver.

WinISD is giving you accurate enough numbers, with the large size due primarily to the high Qts, which BTW is too high for a standard vented design, making either sealed, aperiodic, or OB the obvious choices for a MTM, though you could do them as isobaric to reduce the cab size for a TM.

Anyway, since they will need a sub regardless, ~aperiodic would be my choice to get a good blend to it around 80 Hz and keep the cab size reasonable, so I recommend a MTM TL.

Yes, simulated response through WinISD.

I agree, this driver has a high Qts rather adapted to a sealed enclosure.

If you want them to operate fullrange, maybe this driver isn't the most adapted.

Try simulating a transmission line using Martin's worksheets

Various Transmission Line contours (TQWT, TL, straight pipe...) can fit the widest range of driver possible I think, so it may be worth a try !