Kbd speaker thoughts

[mashaffer]

I am looking to build a speaker system to use with my Yamaha Kbd mostly out of parts I have on hand. For power I have a Peavey XR-600G mixer amp (200W for main mix and monitor).

The drivers I have are
- 15" 8ohm from Wurlitzer organ (fs 45, Qts 0.3 Vas 12 ft^3)
- 6x9" FR from the same organ along with the 2nd order crossover that crossed between those two speakers.
- 16ohm FR with whizzer from the synth on the Wurlitzer organ (fs 86, Qts 1.0)
- two 16ohm AlNiCo speakers from a Baldwin organ. (unmeasured but seem to be designed for OB)

The system will be used for small venues (less than 100 people typically).

My first idea was to use the 15 and 6x9 with the existing crossover but the simulations indicate that the only way to get reasonable bass response would be a very large EBS box or a TL. In fact the TL should provide outstanding results but the size is just a bit much for what I am trying to do so I am considering a couple of other ideas.

Number one on the list is to use one of the Baldwin 12s open backed with a supplemental Piezo tweeter and use the 15" in a ripole configuration. I would probably include a second order passive low pass on the "sub" based on actual response measurements (necessarily crude measurement). This layout should be of very manageable size and cover the range I need as long as I get some of the fs lowering of the ripole.

My thought on the passive LP is to start rolling it in right where the rise from the first "pipe" resonance begins in hopes of flattening that first peak and rolling off enough to make subsequent peaks immaterial.

I could use the 10" dual cone instead of the twelve for simplicity sake but I kinda wanted to save that driver for a HT OB center channel. Also the piezo would get more of the highest harmonics.

I could bi amp using the power amp for the monitor circuit on the sub but I kind of wanted to have that amp available for use as a monitor for vocals. My hope is that the passive crossover would work since the 12" would draw only half the power due to its higher imp. If there is still a slight imbalance I could probably pull it into line with the graphic EQ on the amp.

Any thoughts? Am I way off base here?