Center Channel vs bookshelf as a center

It'll work for certain purposes but a dedicated center channel speaker is better for most applications.

One of the original purposes for surround sound was for music and it was recommended that all 5 speakers be the same for optimum sound with multichannel SACD or DVD-Audio. That's impractical for most people who have home theater systems with a TV. It also doesn't work as well for movies where most of the sound for dialogue is centered in the center speaker that needs to have width to better blend seamlessly with the main front speakers.

If I didn't have a center channel speaker that's designed to perform as one I'd be fine with an LSiM 703, but wouldn't want to keep the system that way. I've seen bookshelf speakers tilted on the side to serve as a center speaker, but the drivers aren't really oriented to serve that purpose. Some may be happy with it, but in my experiments it just didn't work well.

I am using a 703 as my center channel and its tweeter and midrange are at the same height as the tweeter and midrange on my left and right 705s. While 3 identical vertical speakers are the ideal, 3 speakers with the same tweeters and midrange, all vertical and at the same height come very close to that ideal.

The "width" of the horizontal center channel speakers causes "beaming" and limits the horizontal dispersion of the sound from that speaker, thus compromising the frequency responses for anyone sitting other than in the middle of the room. It makes it hard for the 3 front speakers to blend together to form a seamless sound field, when one has a different off-axis response. The only advantage of the horizontal center channel speakers is that they often fit better in a cabinet or under a TV, or the WAF. No other speaker in a home theater is horizontal and there is a good reason for that. The physics of sound are the same for all speakers and the center channel is no different.

The two drivers in a horizontal center channel help with bass response, but if you are using a subwoofer, then that may not be necessary. Having 2 woofers, however makes things worse for off axis response as they cause beaming or narrowing of the off axis response and at various positions in the room they either reinforce or interfere with each other (combing).

My 703 works well as a center channel and has no problem playing at fairly high levels as my subwoofers handle the low bass. While I could have simply used 3 703s up front, I liked the 705 towers rather than 703s on stands for the left and right. Since, in my setup, the tweeters and midrange drivers are all at the same level, AND subwoofers handle the deep base, this setup is just as good as 3 towers.

Coralinus wrote: »

Right now I have 705 towers, 703 surrounds and 704c center. Its a nice set up but the room is large with several seating positions off axis. We have twelve people living here currently and so its hard for everyone to sit on axis. I just keep wondering if it could be better with a change to either to a 703 (as I have room vertically), or if a 706c would be a good choice with the two 6.5" drivers. I probably don't have room for another tower.

As you can see from the link I posted, even the $2500 horizontal W(T/M)W center had better smoothness of its horizontal frequency response when measured in a vertical position.

https://www.audioholics.com/loudspeaker-design/vertical-vs-horizontal-speaker-designs/conclusion-rankings-and-evaluation.html



So, the 703 could work just fine but you give up some dynamic range to the dual woofer center channel designs and towers. Either a 705 tower or 706c mounted vertical would be the best option. LOL!. Not always practical for all but possible for some.





While it's nice to talk about the theory, you already have the 703's. Just temporarily run one as a center and see how you like it compared to the 704c. There you go!