Fantom Center Channel Question

[Phil_RC_1]

Years ago I had no good place for a center channel speaker so I used to set my Dolby surround decoder to phantom center channel. Pretty simply concept since all channels were multiplexed out of the two stereo channels anyway. I didn't feel the sound was missing anything.

Now with the "Discrete" channel type surround formats and receivers, can they be setup for phantom (or NO) center channel without missing any of the center audio track? Pro's and Con's??

If it helps, I have an Onkyo TX-SR706 which does have the option for "NO" center channel.

TIA, Phil

[Chris D]

Sure, if you simply can not do a center channel, then using a phantom setup is the best you're going to get, and it's not bad. However, if you have the option, then yes, you absolutely want to use a center channel. It's the most critical of all speakers for video watching, and you'll get noticeably better audio quality and especially sound field expansion and sound placement, with a good quality center channel.

[krips]

From what I've read, phantom centers have the following pros/cons:
Pro:
- If would have be using unmatched center, could provide more seemless soundstage
- If using higher-end receiver, should not lose any information passing to the speakers
- Better looking having no center, and less money out of your pocket

Con:
- Less drivers producing more content could possibly reduce dynamics?
- Smaller sweet spot limits the usefulness for those who will have others sitting off axis.

[Phil_RC_1]

I have a center now BUT, I have the same problems that almost all HT installations that I have seen have. My L&R mains are lower then the center or if I put the center under the TV then the mains are higher, either way it's a bit of an unbalanced effect when sounds pan from one side through the center to the other side. I really don't want an MTM laying on its side either! which is theoretically the wrong way to do it, but it seems to be the most popular solution for the center. In the end, I'm just wondering if a phantom is actually a better way to go for most people.

My last receiver was an HK 5.1 and it didn't give me the option of a phantom center. The Onkyo does so I'm currently trying the "No Center" option and I'm liking it so far. In a few day I'll go back to the center and see which I prefer.

Thanx for the advice/opinions, Phil

[David Meek]

One thing that will help with the center channel being too low or high is to angle it up or down so that it points directly at ear height at the listening position. This will minimize any distracting localizing of the soundfield. There are several nice stands available, especially for speakers below the screen.

[1oldguy]

In theory it's fantastic to use say 3 of the same speakers for the front end of a system.But for most people it just isn't practical as ceiling height prevents it.But for those that can why not.

[George Bellefontaine]

One thing that will help with the center channel being too low or high is to angle it up or down so that it points directly at ear height at the listening position.

This is what I do with my center speaker as it sits on a stand below my fixed screen while the L&R are fixed to the wall on each end and a bit higher than the center's stand.

[Chris D]

Sure... unless you have a front projection setup, and use an acoustically transparent screen (which I did in my previous theater) everybody in the world has to deal with the issue of having their center channel either above or below their video display.

Obviously, if it were better to phantom-replicate a center than have a speaker, there would be no need for a center channel at all, and everybody would just use two front speakers with phantom replication. The benefits of more precise sound field placement and the center speaker criticality outweigh the compromise of having to put the speaker above or below the display. Me, if I wasn't able to use an identical speaker for the center, I'd still strongly prefer to match it as best as I could and accept the above/below compromise, than "throw the baby out with the bathwater" and go to the other extreme with no center channel at all.

Again, for those who just simply CAN'T use a center, phantom replication provides a good alternative. In the end, though, it's all about getting the best sound to the owner, and if you personally prefer your setup in ANY given configuration, then go for what you like!

[Phil_RC_1]

The benefits of more precise sound field placement and the center speaker criticality outweigh the compromise of having to put the speaker above or below the display.

That's really my point. The "criticality" of keeping the same apparent height and tonal quality when a speaking scene or action scene pans from side to side. Even if you point the center up or down, it WILL give away that it is mounted high or low and just because it uses the same or similar drivers doesn't mean it has the same tonal quality as the L&R mains. A high quality stereo pair of speakers can project a solid center image even if one is sitting off-center.

At this point, I'm keeping my mind open and still evaluating my setup with the center disabled. In a few days I'll re-enable the center just to see if my first impression of the phantom center was false.

In the end, though, it's all about getting the best sound to the owner, and if you personally prefer your setup in ANY given configuration, then go for what you like!

:B Excellent point and something I think we all can agree on, but this makes a stimulating "theoretical" discussion.

Phil

[Chris D]

That's really my point. The "criticality" of keeping the same apparent height and tonal quality when a speaking scene or action scene pans from side to side. Even if you point the center up or down, it WILL give away that it is mounted high or low and just because it uses the same or similar drivers doesn't mean it has the same tonal quality as the L&R mains. A high quality stereo pair of speakers can project a solid center image even if one is sitting off-center

Well, while we're using the general phrases of "sound placement" and "soundfield" remember that the VAST majority of "sound placement" in multichannel surround sound is is the HORIZONTAL plane, with only a small portion being in the vertical with the height of surround speakers, etc.

Again, if audio engineers at Dolby, etc, got together and said, "HEY, I know how we can fix the compromise of having a center channel above or below the display! Let's just eliminate the center speaker. That will be a better, preferable solution!"

Then there would be no center channels. There never would have been Dolby Pro Logic, and 5.1 surround would only have to be 4.1. In the end, the conclusion is that the smaller compromise of center channel tweeters not being totally co-planar with the mains tweeters, is worth it for the greater benefits of a dedicated center speaker.