Dipole surrounds

[Twisted85]

Hi,

I need surround speakers for my HT and I thought I could make those out of drivers I aldready have lying around. I would also like to try dipole surrounds as I a have never really enjoyed directional surrounds.

I'm planning of using two Peerless 2" FR drivers connected in series, one out of phase, and one 5,25" peerless bass driver on a sealed enclosure.

Fullrange Driver
Midbass Driver

Rough Scetch

I've done some conventional 2-way speakers and dealt with baffle-step compensation, but I'm not sure about this case as it will work as a dipole on higher frequencys, and it will be placed right agains a wall.

If the box would be measured in a anechoic room, the bass driver baffle step would set around 400-500Hz depending of the final box measurements. This is also my intended crossover point.

How should I deal with the bafflestep as the bass driver will be placed less than 20cm off the wall? The bass driver sensitivity is rated 87dB and the FR drivers are only 82dB (and will be connected in series), so I'm really wondering how would the overall balance work out. Is the sensitivity difference too much without any attenuation to the bass driver?