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OlderMongrel
01-23-2012, 10:38 PM
Hi all, not much time tonight, but I thought I'd share something on this, maybe append more complete build info later.

This is based on Johnny's suggestion for a cheap, hi-sens system w/ buyout drivers:

10" woof 299-284 (http://www.parts-express.com/pe/showdetl.cfm?Partnumber=299-284&FTR=299-284) (2 per side)
6.5" sealed back buyout mid 289-126 (http://www.parts-express.com/pe/showdetl.cfm?Partnumber=289-126&FTR=289-126)
Pyle horn tweet 272-104 (http://www.parts-express.com/pe/showdetl.cfm?Partnumber=272-104&FTR=272-104)

This is not the tweet Johnny suggested, which would be this:
Foster buyout horn 279-102 (http://www.parts-express.com/pe/showdetl.cfm?Partnumber=279-102&FTR=foster%20horn) I ordered a couple of these, too, and will fiddle at some point.

This is a WWMT. Crossover diagram attached. Four parts per side, 2 coils and 2 caps, B1 all the way. Boxes are old vented sub boxes, about 21" x 17" x 47", works out to about 7 ft3 net. Tuned to 36. This is low for these woofs but room gain seems to even it out. Maybe I will call this "RNC" (red-neck compensation) meaning you tune it to sound best with the bass turned up all the way. If these things end up going to someone else, I bet that will happen. I modeled the XO in Jeff's PCD (thanks, Jeff!). I wanted to use XO stuff I already had (poor assortment), got lucky and was actually able to do it with minor value changes. Some tweaking will no doubt come.

I've played several tracks. The best party track so far is The Burning Sword of Capua and the tracks that follow from Triumvirate's "Spartacus". I took a deep breath and put on some good stuff, Keith Jarrett playing Haydn, some Stacey Kent, Steely Dan, Grandes Heures Liturgiques (Notre Dame organ and choral). It all sounds good. I won't yet elaborate on the weaknesses I heard, but they're very minor considering $40 in drivers for both sides. No fatigue so far. Probably just that the honeymoon hasn't worn off yet.

John

rudyjakubin
01-23-2012, 10:46 PM
No resistor in the tweeter ckt???

Pyle tweeter not to spec???

OlderMongrel
01-23-2012, 10:57 PM
I just crossed it really high. Might need to go a bit higher, or use some resistance, but so far not inclined to.

John

GIS_PHAN
01-24-2012, 09:27 AM
Fun stuff, hope the logo makes it to the speakers!

How does that midrange sound in your build?

OlderMongrel
01-24-2012, 09:58 PM
Fun stuff, hope the logo makes it to the speakers!

How does that midrange sound in your build?

The mid is the weakest point. With this XO, it's not doing much. Inverting polarity yields response that is somewhat different, but you'd not know from the curves what had changed. I might try 2 in series (ordered 4 so I could play) or other options. This will be a fun project to play with.

In some respects the best performance using drivers noted in my OP might be a 2-way with the woofs and the Foster horns. One review of the Fosters notes that with the low end peak, you can cross electrically at about 3k and get about 1.5k net. This models pretty well in PCD, even better active, which I can experiment with as well.

John