Axiom Home Page Forums General Discussion Home Theater Center channel comb filtering

If you have a closed room that is perfectly treated and all speakers are correctly time aligned, and subwoofers are equidistant to mains, and phase and time aligned at the crossover, it may be something to worry about… During intent listening of pink noise while rocking your head back and forth!

At the end of the day, I trust an Axiom product to do its job without fear of design neglect. All horizontal centers, even the best ones, are compromises. If worry is beyond abatement, choose a matched speaker with an AT screen.

I think for CV and Mojo to experience center channel content adequately they need an LFR as a center channel, and a db boost to it vs LR channels, as is the case when a mono signal sums to create a phantom center vocalist. For matched LCRs the center channel should be louder than an auto setup routine would decide.

A point source center speaker vs LFR L/R would no doubt sound unnatural. Integration of the front soundstage would break during pans in content. I would assume the effect would be like a star collaping into a black hole and then exploding again. (Hyperbole of course!)

For 1 or 2 listeners, it makes no financial sense to make this investment. Cheaper way is to use a large QRD diffuser on the front wall behingpd the center channel. Again, an AT screen is needed for this to perform correctly.

My take is non issue in practical applications. Millions are happy with soundbars. “Combfilters R Us”

I think I'd agree with that ...

My biggest question is the behind the screen QRD filter with LFRs (my use case). Would it effect their widened image in 2 channel? I'm hoping it's not an issue.

It's an experiment ...

Mojo, what size screen and how far apart are you're speakers that you can identify the pan so precisely?

Two issues come to mind:

• if the speaker spacing is much more than the width of the screen then the dialog does not come from where the image is when far right or left. A pan across the screen is unnaturally wide ... it's unsetting ... it actually sweeps though the screen as you watch the actor walk 1/2, 1/3, or 1/4 the distance.
• if the screen is small and the speakers are on either side ... then to detect a change in angle becomes difficult.

12' apart. MLP 14'. 5' screen. Backs of LFRs 2.5 feet away from front wall. LCD screen hanging on the wall.

My impression is that when audio comes from on-screen objects, that audio is localized in the center - most of the time. I've noticed in wide angle shots, sometimes there's an explosion away from center and for a critical listener like me, I do see the audio-visual discord but it doesn't bother me.

The best way I can describe it is that the centre image fills the area of my 5' screen. It really does sound like the image source is at the screen center and expands from that point. The 160 did that but it was less diffuse, more focused, less natural. And not always, but quite often, I hear voices to just right or left of centre. For example, when two people are sitting at a table talking to each other. I never heard that from a physical centre speaker.

I don't find the pseudo center image wanting. Volume is ideal. With the 160v4, it was too focused relative to what I have now and sometimes I had to bump up the center gain. Not nearly as much as with the 150v2 though. I have never found the pseudo center image to be too quiet even in older movies.

Well, I think it's fair to call this a non-issue.

I'm disappointed that EAC, Audioholics, and ASR ought to be on the front lines of sweeping away audio myths, but are just perpetuating another set of myths to a newer generation who doesn't know any better. I'm sure I'd enjoy a Dutch & Dutch 8C, Genelec 8361A, or Revel Salon 2's in my living room too, but I think they grossly overstate the increase in marginal utility because Erin and Amir have the bias that if it doesn't rock 105 dB, then it's a compromised design. (I live in a duplex, so that's not a performance target I value)

The only place I get reliable information nowadays is from Andrew's Axiom Audio YouTube channel. I sort of laughed when I rewatched the video on DAC's and he was trying to subtly hint that they're excess unless you're streaming from a computer. He walks that fine line of trying not to offend the hard core audiophile, but I don't even think that's Axiom's target market. If it were, their marketing would look more like Bryston's.

I've tried this with two difference screens with my LFRs about 12' apart.
With my 27" monitor (was using it to setup the 8805). Playing a movie on a 2' wide screen and having the sound stage at 12' was disturbing. Then I hung an old 46" TV which made the setup almost viewable but not realistic if the sound was not somewhat centered.

I wouldnt hold anything against Amir or Erin. They are doing their best and their work is invaluable!!

They just dont or cant present audio as a holistic approach. Honestly, their content would not be as digestible if all factors were covered with as much oversight. Too much to sift through.

I should make an opinion thread with my ranked factors of sound reproduction. Frequency response would not rank as high as I used to believe. My DIY towers are junk by Amirs standards. Junk! Lol.

Honestly ...
if you started in with it's possible to hear this but in most cases you won't notice it ...
Your mail box will fill with all the people who will tell you they would notice (probably with a few words rating your intelligence )
But you can say that you never noticed it ... then they will be ok with it because you just have a hearing problem

I've been in this hobby for 3 decades. The more I research, the more I think the future of home audio is wireless sound bar systems. I did an experiment to see the minimum width a 3 channel bar had to be to be perceived as a soundstage rather than a mono point source from my 8 foot seating position. It's 40 inches, and a neutral frequency response goes a long way in making it a viable alternative.