I am planning on building a pair of the 25hz tapped horns. Will I need to delay my main speakers for proper integration and best SQ? I am not a fan o digital delays, finding them too audible in my very revealing system. Thanks for any input especially from those using the horns.
This is what I think everyone interesed in subwoofers should read: http://www.gedlee.com/downloads/rooms%20and%20sources_norm.pdf There is no timing issue in a "normal" listening room. We are listening to the room modes (resonances) that are essentially impossible to absorb with any WAF. Also look up Dipole, Ripole and H-Frame for some real ear openers! http://www.linkwitzlab.com http://www.hometheatershack.com/forums/diy-subwoofers-general-discussion/7806-ripole-test-sub-build.html
Phase and delay aren't the same thing (though related). You will want to adjust at least polarity (if not phase) to get the best combination. Not necessarily 'matching', but whatever combo gives the smoothest result. The room is a big resonator, you aren't going to time any sub frequency impulse responses in it, but you do want to deal with the phases of everything to contributes that all the modes.
Actually the polarity, phase or whatever one wants to call it, is required only when the eyes instead of the ears decide speaker and subwoofer placement. The cancellation between the main speakers and subwoofers only applies when they are close to one another. As far as frequencies below the rooms ability to create a standing wave, we have an interesting effect called compression. That is why we have bass in an automobile. When the windows are closed, we are in a more or less pressurized chamber and that pressure has a direct effect on the eardrums. Open the window and the bass is reduced to the standing wave. The same applies in a listening room. If you have a smallish room, use a big woofer and leave the doors/windows shut........
With 2 TH subs try a flanking configuration. I've tried TQWPs and placed these in the back with sealed or ported in front. Still experimenting. IME, delay will only be somehow effective and/or predictable if the phase tracking of your mains and sub complement each other. However, this is further complicated by room acoustics. That said, on some recordings proper integration result in better soundstaging/imaging. Instrument timbre from drums, brass, piano. Portrayal of recorded space. There seems to be a lot of space/depth/width/locational information. Bass will tend to be softer or rounded. Then again, I might be "hearing things" 'cause this effect happens sometimes even when bass is recorded in mono.