Erin’s Audio Corner posted his long awaited video on center channel comb filtering a few weeks ago. It’s best to watch the video in its entirety to understand what that means. TL;DR, horizontally arranged drivers of the same size tend to promote comb filtering effects, where sound has amplitude peaks and valleys caused by constructive and disruptive interference. (The vertical effect doesn’t bother us because our ears are horizontally arranged).

He talks about the most common center channel configurations (M = midrange driver, T = tweeter, W = woofer, C = coaxial tweeter with midrange): MTM, MMTMM, WMTMW, WCW, WTTW, WTMW.

https://youtu.be/GZrdsxrcpBw

This topic has been around for decades. Audioholics noted this issue a long time ago:

https://www.audioholics.com/loudspeaker-design/center-channel-speaker

https://www.audioholics.com/loudspeaker-design/comb-filtering

On the other hand, Alan Lofft thought this as inaudible beyond listening to pink noise:

https://www.axiomaudio.com/blog/comb-filtering-popular-misconceptions/

Erin measured up to a 5 dB difference at the seating position, a very noticeable effect. My own center channel, an Angstrom Modular Six, has the worst configuration (TMT) possible for comb filtering, and I can clearly hear the artifacts when listening to pink noise. Here’s the thing: I don’t notice it on music or dialog at all. In fact, it’s a good timbre match for the M5HP mains once I dial away the lifted top end that all my Angstroms have (though it runs out of steam if I push it beyond 75 dB).

So I’m siding with Alan for now. What’s your experience with your center channel setup?

Last edited by Hambrabi; 02/21/22 04:17 PM. Reason: Forgot to add YouTube link
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