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Posted By: jtmccoy phantom center channel - 12/09/04 07:07 PM
Hey all,

Slowly moving up from 2.1 to 5.1 and just pulled the trigger on a pair of QS4's. I'll have to wait just a few more months before I get the spare change to buy a VP100, so I was wondering, will 4.1 still sound pretty decent in the meantime? Has anyone else used this configuration? What's the main thing that I'll be missing?

Thanks,
JT
Posted By: Capn_Pickard Re: phantom center channel - 12/09/04 07:19 PM
It will sound just fine in the meantime, so long as you are seated in the prime listening position. If you are seated in between the front left and rigth speakers, the stereo image of the front pari should yeild a phantom center, where the voices seem to come from in between the speakers. However, if you move to one side or the other, the effect will collapse. That said, its not the end of the world.

With a 5.1 system, the problem is obviously solved by rooting the center channel in the middle, meaning that there will be better off center imaging of the voices when not listening from the prime position.

I usually always have my center on when watching TV. But a few night ago, I was fooling around with the DSPs on my receiver. A couple of them utilize a phantom center channel. Admittedly, I was fooled by this, and actually had to walk up to the TV and put my ear against the speaker to see whether it was playing or not.

Like I said, you won't be missing any sound, per se, but the effect will collapse once you leave the prime position. I think that you made a good choice by getting the surroudns before the center, if you had to choose. The surroudn effects are harder to "fake" than a center effect. That said, many posters here will tell you (and I agree with them) that the center is ultinately the most important piece of the puzzle, as so much movie information is fed to that speaker. But as far as dazzle, wow and fun factors go, the surrounds will really get your heart pumping. Worry about the other stuff later.
Posted By: dmn23 Re: phantom center channel - 12/09/04 07:51 PM
I think Kcarlile has been using this setup for quite a while, hasn't he?
Posted By: pmbuko Re: phantom center channel - 12/09/04 09:00 PM
Not exactly. Through some sort of creative wiring scheme, he pipes the center channnel signal through his TV speakers.
Posted By: Ken.C Re: phantom center channel - 12/09/04 09:18 PM
Here's what I do. I switch the TV speakers to mono, plug in the cable from the center out to the left TV analog in. Then I turn up the TV a whole lot and also boost the output on the reciever to around +6. It kind of works. I also have it crossed at 120 Hz to the sub (for the center channel alone). I do NOT listen to music this way!
Posted By: mwc Re: phantom center channel - 12/09/04 09:19 PM
Do an Axiom search for phantom going back at least two weeks. You'll find opinions on using no center.

You won't miss a thing as long as you are in/near the sweet spot. The only advantage I can see to a dedicated center is that it anchors dialog to the screen for those sitting off axis. The disadvantage is that, IMO, center speakers never sound exactly the same, particularly in timbre and soundstage scale, as the LR mains.
Posted By: mwc Re: phantom center channel - 12/09/04 09:40 PM
In reply to:

That said, many posters here will tell you (and I agree with them) that the center is ultinately the most important piece of the puzzle, as so much movie information is fed to that speaker




Which is why it is so important to either get the best match for the LR mains (exact same speaker would be the ideal albeit not practical) or go phantom to ensure that the center material exactly matches the sound from the mains. If there is no concern about (far) off-axis listening (out of the sweet spot) a center is an added expense that most can do without.

Obviously, if one has a huge room with lots of folks sitting near the side walls then a dedicated center becomes essential.
Posted By: Ken.C Re: phantom center channel - 12/09/04 09:45 PM
I have a fairly small room, but I was not at all satisfied with the phantom center. Maybe I just didn't have the speakers placed well, but it seemed very lacking to me. Hence, my solution from hell.
Posted By: pmbuko Re: phantom center channel - 12/09/04 10:13 PM
temporary solution from hell, right Ken?
Posted By: Ken.C Re: phantom center channel - 12/09/04 10:31 PM
Yes. I think Jen is willing, but the wallet is weak. We still need to settle on where it will go... (how's that behind TV stand going, Mark?)
Posted By: mwc Re: phantom center channel - 12/10/04 01:06 AM
What was it lacking?
Posted By: Ken.C Re: phantom center channel - 12/10/04 01:08 AM
I probably wasn't in the sweet spot, but it sounded to me like the sound was coming very clearly from the L and R speakers, not the middle of the TV. I don't have this problem when I use surround processing on CDs and only listen in 4.1. It's also been awhile since I've tried it.

Actually, it was the lack of a center channel that led me to these forums! I tried watching T2 Ultimate Edition in 2.1, and I could barely hear the dialog. My first post was about whether I should get an Axiom center or some other brand... and I still don't have one!
Posted By: bridgman Re: phantom center channel - 12/10/04 03:01 AM
As long as your receiver can accept a "NONE" option for the center channel and route the center signal to the L + R mains you're not going to miss much. I ran that way for quite a while, then single M2 center for a while, finally settled on a VP100 mostly because of the shielding.

I did find that the dialog was a bit more clear with a center, even with M60s as mains, but the difference is pretty small.

As everyone has said, the other benefit of a center speaker is that you can sit a bit to the left and right of the sweet spot and still hear voices coming from the right place on the screen. Without a center speaker if you sit to the left the voices are going to sound like they're coming from the left edge of the screen.

Anyways, don't sweat it. 4.1 is gonna sound way better than 2.1, and you'll still have 5.1 to look forward to...
Posted By: jtmccoy Re: phantom center channel - 12/10/04 03:37 AM
Sweeeeeeet. Thanks for the replies guys. One of you said that the phantom center works better the closer your mains are to each other. Based on that logic, then, wouldn't adding a center also help expand your soundstage, because you would be able to spread your mains a little further out?
Posted By: alan Re: phantom center channel - 12/10/04 02:23 PM
Hi jt,

You got it. That indeed is another virtue of using a center, to avoid the "hole-in-the-middle" effect when the main speakers are widely spaced, and to minimize the collapse of the stereo image when listening off-axis to the left or right.

In the 1930s, Bell Telephone acoustical/electrical engineers experimenting with multi-channel live transmission (over telephone cables) of concerts by the Philadelphia Orchestra concluded that a "minimum" of three channels--left, center, and right--were necessary to realistically portray the stereo soundstage of the orchestra.

Recording technology at the time was not up to the task (only mono was possible), but engineers even then recognized the serious limitations of mono or two channels (stereo).

Regards,
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