Hello all,

After months of planning, I finally cut some MDF and took some measurements.

My project is something really new for me. It's an OB / vented woofer hybrid, with a hybrid crossover: passive on the mids and highs, and active between those two and the woofers.

The OB is an MTM with two RS-150s 8's and an unbaffled Neo3 PDR. The vented woofer module has 2 RS-150s,

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Those are a couple of SketchUp modules I drew before cutting wood, in order to have an idea about their size, etc.

After cutting wood and doing stuff, today I began measuring them.

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There are a couple of things:

1) The panels are slightly larger than the final versions (by 2 cms)
2) The panels are slightly wider and with different offsets side by side (by 4 cms)

Everything else is as it should be - the woofers and tweeters are recessed, etc.

I only measured the upper OB module.

Here are the measurements I got from 0, 15, 30, 45, 60 degrees from the woofers.

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I have an issue here. At 1,600 Hz.

When I try to design a crossover at 1.9 - 2.0 KHz, the optimal points for my drivers, the 1,600 Hz (dipole peak? Is that it?) shows its ugly face as a bump in the overall frequency response. Ack.

It's nasty.

My questions are: is it avoidable? How can I avoid it? Going to a wider baffle? Narrower? Must I play around with the crossover points?

Any help will definitely be greatly appreciated!