Sub for 4406?

[speakerdave]

A great woofer for this job would have been the 2203. It is no longer available, of course, but JBL has a modern woofer which is like an improved version of the 2203-the 252G. See Giskard's graphs comparing the two in 2.5 cu. ft. boxes on this thread:

http://audioheritage.csdco.com/vbull...highlight=252g

David

[Figge]

I'd be cuttin' wood on that one if I had a pair of those sittin' around....

[johnaec]

A 12" 128H might make a good little sub. There's one on eBay right now:
http://cgi.ebay.com/ws/eBayISAPI.dll...MEWA%3AIT&rd=1

John

[Guido]

I went this way for my 4313B


http://audioheritage.csdco.com/vbull...highlight=2203

[Zilch]

128H, in a 4th order bandpass box. Front chamber 1.0 cubic feet, rear chamber 1.5 cubic feet. Front chamber tuning, 55 Hz.

Only problem, is that there's SO MUCH volume displacement possible, getting a port in there is the challenge.

C'mon, Gordon, we KNOW you can do it for us. You're mighty clever with those slotted-port designs.

One for LE14A, and one for 128H, please....

[Lotsa LE14A out there need "application."]

[GordonW]

Problem is, to get enough port area (8" diameter tube, minimum!), you're talking about a port that's between 3.5 and 4 FEET LONG. Once you get into that length (which is greater than a quarter-wave at 70 Hz), it starts acting as an ORGAN PIPE, rather than a lumped Hemholtz tuning mass.

Definitely would need to be a PR... in the 128H bandpass box design above, my suggestion would be to use a 15" PR, with about 13.25 ounces of total cone mass, to tune the front 1 ft^3 chamber. Something with some fairly serious excursion, too... like an Adire or Stryke Audio 15" unit. You'd want at least 3-4 liters of volume displacement...

Regards,
Gordon.

[Zilch]

Gordon, I've just modeled a single 128H in 4th-order bandpass as you describe, and it's good like you say.

BUT, I'm getting more reasonable vents: 3" dia. at 3.307" long, and 4" dia. at 7.213" long, either of which would fit.

It'll take 79 Watts without compromise, and the full 100 Watts with concomitant distortion below 30 Hz, is all.

Something I'm missing there?

F3's are 30 and 100 Hz....

[Gonna try it isobaric, now.]