Line Array Speaker vs Point Source Speaker

That's quite a compliment Duke!

How do line arrays deal with "comb filtering", or is it not an issue?

Hce4, comb filtering in the vertical plane is dealt with by having the inter-driver spacing small in relation to the wavelengths produced, and/or using drivers that inherently have limited vertical dispersion anyway and therefore little or no overlap vertical overlap (like the full-height ribbons in the modules that make up the Dali Megailne).

In the horizontal plane, we want the inter-driver spacing as small a possible in relation to a wavelength at the crossover frequency. A steep crossover also helps to prevent lobing in the horizonatal plane by narrowing the frequency region covered by two drivers.

Some prosound line arrays have slot-loaded compression drivers flanked by a pair of midwoofers. The slot loading of the compression driver gives it a narrow horizontal footprint but wide horizontal coverage, along with narrow vertical dispersion (which minimizes vertical comb filtering) in a format that allows a fairly low crossover frequency so that the flanking midwoofers don't beam too badly in the horizontal plane in the crossover region. With the right crossover, it should be possible to avoid any deep nulls in the horizontal plane within the coverage angle of the array.

Duke

That's high praise for Soundlabs when it comes from your keyboard, Duke. One thing I've learned to appreciate from my line arrays (which you've listened to in my home)is their preservation of dynamics and detail at low listening volumes. It's counter to the oft-given kudos for high volume listening performance that arrays generally receive. The addition of outboard subs which can be dialed in for low volume output complementary to the arrays makes for one of the most satisfying low listening volume setups for me. Wife and neighbors agree!