dc270
Now Off the Reservation
Can you direct me to Wayne P's crossover? Thanks for your information here- maybe there is wave guide hope for my "Z's" after all!
DC
Zilch's AK Design Collaborative - Econowave Speaker
- Thread starter Zilch
- Start date
Can you direct me to Wayne P's crossover? Thanks for your information here- maybe there is wave guide hope for my "Z's" after all!
DC
Russellc
Addicted Member
Great info! So for the Hi Eff. version, R1= 6 ohms, R2= 40 ohms, and C3= 1.5 uf. Cant wait for the Low Eff. version, I'll order the parts and put DE 250 on the QSC horn and report results.
Thanks for the info, much appreciated!:yes:
russellc
Bauhausler
Rational Subjectivist
When you say using the Ewave compensation, did the crossover also include the C/L HP components, or just the RC/R compensation parts?
Don't know if the site will allow me to upload images yet, but the standard efficiency components I worked up yesterday are R1 = 16 Ohms, R2 = 16 Ohms, and C3 = 0.47. You only have to change one resistor. That's not final, of course, just what my preliminary measurements indicate. I believe it's fair to call the QSC a waveguide.
I'm using the stock highpass; I'm reluctant to alter that, initially, at least.
Just the fundamental one: in detail, each driver/waveguide combination is different, and requires different compensation. Once that is done, and only then, is it possible to compare the actual sonic performance....
350087/6924=50.5614
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Russellc
Addicted Member
The original. They're running with 2206H as LF, and the crossover measures 1.8 kHz.
It could go lower, but I've got to optimize the lowpass for that woofer, first; it's summing well, but the midrange is a couple of dB "forward."
Skywave wants to know how low. Answer is, I don't know. Geddes uses DE-250 way lower, despite the B&C recommendation of 1.6 kHz minimum. The waveguide is a factor in this also -- Augerpro's polars suggest it's losing pattern control in this region, so a complex of competing factors must be balanced to arrive at an "optimum" blend. We'll know more once he gets measurements on his completed system. :yes:
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Russellc
Addicted Member
Go to the Pi site and scroll down a ways, you'll see a post talking about the new 4PI crossover. Or just send Wayne a message and he'll forward it to you, get his crossover document while you are at it. That 3PI looks interesting, using the AE 12 incher and B&C DE 250.........
Russellc
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Russellc
Addicted Member
No more than a lowpass filter would. I believe we know what the foam plug does; it would appear to be transparent in that range....
:yes:
Russellc
Addicted Member
Just a thought, I understand he gets them to crossover around 900 hz.
Only picture (courtesy of Zilch) I've seen of one of his crossovers had at least 3 notch filters to tame it, maybe they help?
Russellc
hhibrownsbac
Super Member
Try looking in post 4894, i dont know if hes updated it at all but I was using this one with a DE250 and 2225H and was real happy with it while I had it up and running.
He uses a different HF comp scheme, but one notch @ 4.5 kHz will get this combo into +/- 1 dB territory. It's kinda academic 'til the system is in a cab, but I may work on that a bit, anyway.
If you swapped in 16 Ohms, we're listening to the same thing right now.... :thmbsp:
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JBL inverse-polarity woofers, invert the connections after verifying with a battery that they remain inverse on the external input terminals. I've outsmarted myself a couple of times by reversing them internally and not sticking a label on the outside saying so.
Tweeter is connected standard eWave polarity.... :yes:
Tweeter is connected standard eWave polarity.... :yes:
skywave-rider
Slumming in Akihabara
I like the PE knockdown trapezoidal cab Bauhausier found.
Anyone care to speculate on whether or not the recessed baffle will be a diffraction issue? My theory is no...because the lip is too small for the woofer's frequency range to interact with; and the waveguide will limit the pattern to avoid the edge.
Or maybe I should just double up the baffle and build it out? But I got no skills...
Zilch or Russell, do you have dimensions for the QSC guide? I want to see if it will fit.
Thanks for the graphs and pics you guys.
Anyone care to speculate on whether or not the recessed baffle will be a diffraction issue? My theory is no...because the lip is too small for the woofer's frequency range to interact with; and the waveguide will limit the pattern to avoid the edge.
Or maybe I should just double up the baffle and build it out? But I got no skills...
Zilch or Russell, do you have dimensions for the QSC guide? I want to see if it will fit.
Thanks for the graphs and pics you guys.
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14" x 10".
As you suggest, it looks like the front baffle could be moved forward, if desired. A PE or window screen grille could fit nicely in a smaller recess. I'm also thinking rear mount the woofer and slide the waveguide down to minimize the C/C distance. It's looking like it will all fit.
What're we talking here:
Cabs - $128
DE250s - $250
Waveguides - $22
XOs - $100
Total - $500 plus woofers.
It'll work, but it ain't "Econo...."
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skywave-rider
Slumming in Akihabara
Some airtight trim in front of the stop to bring the baffle forward...maybe not too hard to do. That will make a gap, but I think that will look good. I will make the baffle removable....Zilch...sold!
1st iteration: JBL 123A1s which are on hand, sealed.
If that sucks, Eminence Kappa 12s ported.
1st iteration: JBL 123A1s which are on hand, sealed.
If that sucks, Eminence Kappa 12s ported.
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skywave-rider
Slumming in Akihabara
What're we talking here:
Cabs - $128
DE250s - $250
Waveguides - $22
XOs - $100
Total - $500 plus woofers.
It'll work, but it ain't "Econo...."
True. Hard to beat the EWaveguide/Selenium driver for bang-for-buck. That's a lot of bang.