point me to low $ midwoofer for 1st order 2 way

[kifeinthesink]

I need an inexpensive midwoofer to match with 27tdfc that has a nice smooth curve and will allow me to use first order xo. Im going to fiddle around with some simple xo's. Think vifa p13 kind of thing except $30 give or take abit. I'll probably use it ported but maybe sealed.

[kifeinthesink]

any reason why this might not work. Curves look pretty amazing. Seems abit to good to be true though.

peerless 831990

data sheet

[Roger Hill]

The Peerless will work, but I don't like the upper end for a true 1st order crossover (I mean a first order acoustic slope). I think you would be happier with this one:

http://www.gr-research.com/drivers/m130.htm

which has good response to above 10kHz and greater sensitivity also. At $26.95 it is within your budget parameters.

Roger Hill

[kifeinthesink]

excellent. When Im done I can use them for dennis murphys design with that driver and the 27tdfc. Might pick up the peerless too since they're only 10 bucks

[Roger Hill]

A couple of suggestions for how to do first order crossover: First, do a preliminary first order crossover with a cross point at about 2500 Hz. You'll need only an inductor for the woofer and a capacitor for the tweeter BUT: to the tweeter circuit, add a shunt inductor of about 2 mH between the tweet and capacitor for protection. This will greatly attenuate the tweeter response below 1 kHz. Tweak to get a good match to the 6 dB slopes for both the woof and tweet. a match within a few dB over two octaves each side of cross point is your goal. Mount the woofer in the box, seal the tweeter hole, and make a simple "L" shaped baffle for the tweeter, open backed is fine since the tweeters are sealed. Turn the woofer box upside down, set the tweeter on it and slide the tweeter back and forth until you get flat response. This will tell you how far behind the woofer the tweeter has to be to get the "acoustic centers" aligned. Make a new baffle with the proper offsets between the woofer and tweeter, mount the drivers and start dealing with all the bumps, wiggles, diffraction, etc. Now, you are ready to start the hard work of getting the speaker "right". One trick that is helpful in getting the high end of the mid woof right is to use an inductor in series with an RL parallel circuit for the mid-woof crossover topology........one of those things that just helped in getting a first order slope in previous project. Once you have listened to a transient perfect system, you won't want to listen to anything else.

Roger Hill