[brianpowers27]

I am considering another dipole.  The current dipole sounds great but is a little power hungry

I have the following:
--250$ PE gift cert
bash300 amp
4xrs225-8
2xrs28a
1xrs150s8

I am thinking about putting one emininence 15 alpha in each side (8ohms) and paralleling them to the plate amp. Crossing off at 150hz.  The rs225 could cross to the rs28 at 1400hz.



The one I have in mind is the short one...  I may also consider the outside design.  THe middle design is there for reference.  This is the North/seas design.

[Angaria]

There was some well-documented dipole measurements of the rs225, try google.

Your edge-on orientation of the 15a looks attractive, but it's gonna put you in the dipole null.

Don't push the RS so low.... the 15a sounds fine up to 300Hz imho and it won't be detrimental to male vocals in that range, plus the remaining midrange on the RS should clear up a bit and you'll gain overall sensitivity.That being said, I'd be tempted to go with one of the b&c woofers if you crossing higher and hence don't need the excursion.

[brianpowers27]

There was some well-documented dipole measurements of the rs225, try google.

Your edge-on orientation of the 15a looks attractive, but it's gonna put you in the dipole null.

Don't push the RS so low.... the 15a sounds fine up to 300Hz imho and it won't be detrimental to male vocals in that range, plus the remaining midrange on the RS should clear up a bit and you'll gain overall sensitivity.That being said, I'd be tempted to go with one of the b&c woofers if you crossing higher and hence don't need the excursion.

Those are valid points regarding the xo point.  Part of the reason I was choosing this low figure was so that I could work with the plate amp xo and avoid passive xo components. I may purchase the low end behringer dcx which allows for a stereo 2way + sub.  If I treat the woofers as the sub, I can cross as high as 230hz.

I realize that the alpha 15" is positioned so that the null is 90 dgrees from where it ordinarily is.  I tilted the rs180-rs28 inward .  If the listener is set on axis with the upper frequency baffle, they shouldn't be in a null.  I may need to rotate this plane further to achieve a better power match.

(See Gradient Helsinki loudspeaker.)

[brianpowers27]

After more thought, the power matching might work better by moving the woofer forward and creating more of a u-frame alignment.  The bass null would then point more toward the outside of the speakers. 

[brianpowers27]

This project still lives...

I built the basic mdf test frames.  (Pics to come later)
I am awaiting a bhringer dcx2496.  I will be using the 7.1 channel analog in on my Harman Kardon receiver to power the output of the DCX.

[brianpowers27]

• Received dcx2496 and connected to my 7 channel harman kardon amplifier
• Configured xo for my combo (alpha 15, rs225, mystery tweeter)
• Listening for several days
• Sound is good, profile is low
• OOPs .  The wings on the bass bin are not deep enough to create a deep cardoid response.
• Bass is very extended and loud, even with a 55watt amplifier.  (97db sensitivity helps)
• For the time being, I have the bass bins rotated.  If I rebuild the bins, I will try to get them back to their original orientation.