that dreaded center speaker

H

herbu

Audioholic Samurai
why would it sound great in phantom but sound bad in the center.
also, i dont know how the distance between speakers can have any effect at all on sound quality if the sound emanates from only one speaker? ie center channel vocals can come from center only or be downmixed to the mains for a phantom center. nothing in between.
Did you read Swerd's explanation above?
I'm beginning to wonder if you might protest a bit too much to be legitimately looking for an answer to your question.
 
B

big O

Junior Audioholic
i read it and it unfortunately didnt make sense to me.

he said that comb filtering is why the center sounds bad and the phantom sounds good? how can you have comb filtering if the sound(vocals) is coming only coming from one discrete speaker?

also, i didnt undertand how comb filtering would be a problem when the setup that sounds best is the phantom center and this would be the one that could have comb filtering artifacts?

very confusing line of thinking to me. unless maybe the vocals in the center is not discrete to the center speaker?
 
3db

3db

Audioholic Slumlord
the poor atom doth suffer much disrespect. it may not be the greatest speaker but it is very good imo for what it is. also,why would it sound great in phantom but sound bad in the center.
also, i dont know how the distance between speakers can have any effect at all on sound quality if the sound emanates from only one speaker? ie center channel vocals can come from center only or be downmixed to the mains for a phantom center. nothing in between.

btw, great to hear your center channel sounds great. perchance have you tried it in phantom mode to see how it compares?
Once for about three monthes when we were trying to sell the house. I had to dismantle the top of the cabinet (see pic) that then housed my primary system. Because the listening area was so narrow, I didn't miss the center channel at all.

upload_2015-7-18_9-4-51.jpeg
 
Swerd

Swerd

Audioholic Warlord
i read it and it unfortunately didnt make sense to me.

he said that comb filtering is why the center sounds bad and the phantom sounds good? how can you have comb filtering if the sound(vocals) is coming only coming from one discrete speaker?
A quick definition: A comb filter, in signal processing, adds a delayed version of a signal to itself, causing constructive (additions) and destructive (cancellations) interference. The frequency response curve of a comb filter consists of a series of regularly spaced spikes, giving the appearance of a comb.
https://en.wikipedia.org/wiki/Comb_filter

Sound occurs in waves. All waves have peaks & valleys. Imagine two side-by-side speakers producing the same sound, separated by a few feet. If you are not sitting exactly the same distance from both speakers, there is a good chance that for some frequency, the sound from one speaker will arrive at the listening position out of phase with sound from the other speaker. Sound from one speaker will arrive at as a wave peak, and the same sound from the other will arrive as a valley. They will cancel each other. Frequencies close enough to that will arrive nearly out of phase, resulting in partial cancellation. And yes, there will also be frequencies where addition not cancellation occurs. Those will be twice a loud. The overall result will be an uneven sound across the critical mid range.

In your case, two side-by-side speakers producing the same or similar signals will act as an unwanted comb filter. The distance between the speakers determines the frequency at which the additions and cancellations occur. If they are close enough, such as 3 or 4 feet, the voice recognition band frequencies can get comb filtered, resulting in muddy sounding dialog.

Sound travels at 1126 feet/second. Sound at 500 Hz has a wavelength of 1126/500 = 2.3 feet. 1000 Hz is half that, about 1.1 feet. It is easy to imagine sound in the voice range getting comb filtered by speakers as close together as yours. When you switch to phantom center, the distance between speakers doubles, resulting in little or no comb filtering in the mid range.

I hope that explanation helps :).

very confusing line of thinking to me. unless maybe the vocals in the center is not discrete to the center speaker?
This is why I asked whether you did the comparison with a 5-channel discrete audio source, or if you used a 2-channel source where the center channel was synthesized. The second case would result in voice coming out of all 3 Atoms.
 
B

big O

Junior Audioholic
Once for about three monthes when we were trying to sell the house. I had to dismantle the top of the cabinet (see pic) that then housed my primary system. Because the listening area was so narrow, I didn't miss the center channel at all.

View attachment 16359
Glad to hear that. i keep messing with the center channel to see what im missing. i believe the centers i tried and the location just were not a good fit for my room. what ive noticed in my room is speakers sound very different depending on location. even the left and right speakers sound different(and since i have 2 pairs of numerical atoms that ive tested in multiple different iterations, i can attest it is not the speaker sounding different but the location( or maybe my amplifier outputs sound different- i havent tested that one yet)

however if i send some pink noise through the left, center, or right, with identical speakers, the sound has different "notes" akin to playing do re mi on a piano.

here is what ive tested so far.

-klipsch rc52 below tv- NO
-paradigm cc170 below tv and above tv- not a very good sounding speaker in general and eq makes it better but still not good
-paradigm atom as center-above and below, one only or two side by side, horizontal or vertical- good sound but still sounds very different summing left and right, not a big sound.
- ive even tested the t6 as a center, with the tv sitting right on top of the speaker - very good sound- could actually live with this one, but if speaker is centered, sound is not centered, and i would never be able to live with an uncentered tower below my tv.
-phantom center- sounds great in my room, regardless of speakers im using but no option to increase just the center volume.

so, i can see myself liking a center if i can have a GREAT speaker, like a t6 quality or better, thats deep enough to set my tv atop(14 inches front to back). anything else and the phantom just would be better.

also, sometimes i notice that the phantom vocals are louder that coming from the real center,even when i have volume matched exactly.i dont know if its the preamp summing algorithm.
 
B

big O

Junior Audioholic
This is why I asked whether you did the comparison with a 5-channel discrete audio source, or if you used a 2-channel source where the center channel was synthesized. The second case would result in voice coming out of all 3 Atoms.
oh, i see where you are coming from now. i should disclose that the only problem i have with the center channel is voices. instruments sound fine but i guess i am sensitive to voices and it just pulls me out of the movie if they sound off.

to clarify, i used discrete signals for testing,not a two channel source.
 
Swerd

Swerd

Audioholic Warlord
… the only problem i have with the center channel is voices. instruments sound fine but i guess i am sensitive to voices and it just pulls me out of the movie if they sound off.
You aren't the only one. Except for people born deaf, we all have great familiarity with how voices sound. But most of us aren't so discriminating about music reproduced in home audio, unless you are a musician or spend a lot of time around live music.

That's why its a good idea to listen to dialog or normal voices when checking out a different speaker. Most of us can tell right away if it sounds right or wrong. Obviously, your PSB T6 is much better at than the Atom.
 
B

big O

Junior Audioholic
thats correct. its so easy to spot if the vocals are off. especially spoken voice imo.

I need to post a pic tonight. I finally found one location where a center sounds good. I built a box and put the center out in front of the tv with the top just below the bottom of the tv and it sounds good. I just need to upgrade the center and I think I should be ok
 
B

big O

Junior Audioholic
EUREKA- IVE FOUND IT -CENTER CHANNEL NIRVANA!!!

i havent rested in a week trying to figure out how to get a larger than life sound from a center speaker. ive been reading articles on clarity , distortion etc.

well, after a lot of reading i felt that what I was looking for in a center channel speaker was something with high sensitivity, horns, and capable of recreating the full range of audio without the help of a subwoofer. it also just so happens that all cinema speakers are high sensitivity, have horns, and are capable of recreating the full audio range.

wait - what? was i now going to put a huge jbl cinema speaker in my living room so I could get movie theater sound? hell- if thats what it takes.

anyhow, it turns out there is quite the community of home theater enthusiasts out there who actually use cinema speakers in their home theater- and enjoy the heck out of the sound.

so what did I do? before dropped a lot of money on jbl 3622n speakers I decided I would find a speaker that met my requirements locally that was cheap and i could play with to see how I like it.

well, let me tell you- I found a speaker, and I LOVE it!
klipsch kg 5.2 speaker. 96 db sensitivity, horn loaded tweeter, 10" driver and 12" passive radiator, good to 32hz.

I took my tv stand out, plunked the speaker on its side , and set my tv on it(I know- no way that can ever sound good right) and turned on a movie.

WHOA! WTF! this sounds effing amazing. the sound is big,round, crisp,clear,and Vocals sound fantastic!.the speaker virtually disappears .

so i set it from small to large to let it play the full range- impossible! it sounded great before how is it possible that it sounds even better now- so much coherence from top to bottom- unreal.

i finally hear what a good center should sound like. you practically cannot hear the speaker- just the content- and it sounds great. matter of fact, i like it so much that i already want to upgrade it,lol. to an epic cf4 - 2" horn loaded tweeter, dual 12" drivers in a huge box, 108lbs of goodness, and the tweeter is in the middle of the speaker so i dont have to offset the speaker to one side to center the sound. then i can use my kg5.2s as the mains.

here are some big takeaways for me over the last week or so. keep in mind this system is almost 100% movies:

-I prefer to set the speakers to LARGE instead of small(goes against all conventional wisdom i know). many cinema speakers start rolling off around 80hz anyway so im not missing any content if my speakers can go down to 30hz - and the sound is more coherent for lack of a better word. matter of fact im not even using the subs right now

-bigger speaker - bigger driver- bigger box- bigger sound

-a good,high sensitivity horn speaker, is a good thing for movies- i hated my old horn speaker-also klipsch btw, but a good one can be really bring out a great movie sound in vocals. sibilant enough for clarity but smooth.

-for a home theater setup - the center speaker needs to be the best speaker by far since it carries up to 70% of the sound in the movie. and it carries the sound we are most sensitive to-human voices. a compromised center imo is a waste of time and im never going back to a non full range center.

-i never used to understand when people talked about speakers for home theater being different from speakers for music but i get it now. for music the front mains are the most important speaker- for movies the center is the most important speaker.

-id rather have non matching speakers if it means i can get an awesome center channel than get matching fronts with a center channel that doesnt deliver.

any feedback welcome.
 
B

big O

Junior Audioholic
btw, here is the off axis response compared to the sweet spot(black line). the other traces are more than 50 degrees off center.

system was normalized to the sweet spot and flattened. then i took readings from off axis left, off axis right, and back to sweet spot(which is no longer flat and goes to show how big a difference just a subtle change in mic positioning can make)
 

Attachments

H

herbu

Audioholic Samurai
Really glad, especially after all your angst, you found something that sounds great to you!
 
agarwalro

agarwalro

Audioholic Ninja
Nothing like hitting the sweet spot. Where's that FR from?
 
3db

3db

Audioholic Slumlord
EUREKA- IVE FOUND IT -CENTER CHANNEL NIRVANA!!!

i havent rested in a week trying to figure out how to get a larger than life sound from a center speaker. ive been reading articles on clarity , distortion etc.

well, after a lot of reading i felt that what I was looking for in a center channel speaker was something with high sensitivity, horns, and capable of recreating the full range of audio without the help of a subwoofer. it also just so happens that all cinema speakers are high sensitivity, have horns, and are capable of recreating the full audio range.

wait - what? was i now going to put a huge jbl cinema speaker in my living room so I could get movie theater sound? hell- if thats what it takes.

anyhow, it turns out there is quite the community of home theater enthusiasts out there who actually use cinema speakers in their home theater- and enjoy the heck out of the sound.

so what did I do? before dropped a lot of money on jbl 3622n speakers I decided I would find a speaker that met my requirements locally that was cheap and i could play with to see how I like it.

well, let me tell you- I found a speaker, and I LOVE it!
klipsch kg 5.2 speaker. 96 db sensitivity, horn loaded tweeter, 10" driver and 12" passive radiator, good to 32hz.

I took my tv stand out, plunked the speaker on its side , and set my tv on it(I know- no way that can ever sound good right) and turned on a movie.

WHOA! WTF! this sounds effing amazing. the sound is big,round, crisp,clear,and Vocals sound fantastic!.the speaker virtually disappears .

so i set it from small to large to let it play the full range- impossible! it sounded great before how is it possible that it sounds even better now- so much coherence from top to bottom- unreal.

i finally hear what a good center should sound like. you practically cannot hear the speaker- just the content- and it sounds great. matter of fact, i like it so much that i already want to upgrade it,lol. to an epic cf4 - 2" horn loaded tweeter, dual 12" drivers in a huge box, 108lbs of goodness, and the tweeter is in the middle of the speaker so i dont have to offset the speaker to one side to center the sound. then i can use my kg5.2s as the mains.

here are some big takeaways for me over the last week or so. keep in mind this system is almost 100% movies:

-I prefer to set the speakers to LARGE instead of small(goes against all conventional wisdom i know). many cinema speakers start rolling off around 80hz anyway so im not missing any content if my speakers can go down to 30hz - and the sound is more coherent for lack of a better word. matter of fact im not even using the subs right now

-bigger speaker - bigger driver- bigger box- bigger sound

-a good,high sensitivity horn speaker, is a good thing for movies- i hated my old horn speaker-also klipsch btw, but a good one can be really bring out a great movie sound in vocals. sibilant enough for clarity but smooth.

-for a home theater setup - the center speaker needs to be the best speaker by far since it carries up to 70% of the sound in the movie. and it carries the sound we are most sensitive to-human voices. a compromised center imo is a waste of time and im never going back to a non full range center.

-i never used to understand when people talked about speakers for home theater being different from speakers for music but i get it now. for music the front mains are the most important speaker- for movies the center is the most important speaker.

-id rather have non matching speakers if it means i can get an awesome center channel than get matching fronts with a center channel that doesnt deliver.

any feedback welcome.
I'm happy for you that you are able to get the results you were looking for. Good on you. :) However, a good speaker is a good speaker and will work equally well in either HT or music application. If a speaker is only good for one application, I'm inclined to think that the speaker is not a good speaker.
 
B

big O

Junior Audioholic
I'm happy for you that you are able to get the results you were looking for. Good on you. :) However, a good speaker is a good speaker and will work equally well in either HT or music application. If a speaker is only good for one application, I'm inclined to think that the speaker is not a good speaker.
hmm. I used to think that way too :)
but i still think music and movies have different priorities - the mains for music, and the center for movies- this is assuming a fixed budget ie.
I wouldnt buy great mains and a compromised center for movies, nor would I buy a great center and compromised mains for music.
 
B

big O

Junior Audioholic
I assumed it was from some other forum/owner review. Is that the Klipsch in your room? If yes, that's really good.
actually, that graph is a little bit misleading because it was normalized to be flat - before i started testing. all it is good for is comparing different frequency responses in the same session to a flat baseline. i dont have a calibrated mic or a decent soundcard and its a method i use when i want to compare the response of one speaker to another.

with a real soundcard and mic it will look very different from this and probably not very nice.
 
B

big O

Junior Audioholic
Alright, continuing the center channel discussion- it seems i have FINALLY found the reason why stereophonic sound(phantom center) may sound better than monophonic sound(actual center speaker) and why many feel that less than great center speakers are actually worse than a phantom center.

research has been done that suggests that we can better identify the flaws or better judge a speaker, when listening to a single speaker. matter of fact, it was found that a speaker that sounds bad solo, can sound good in stereo- BUT a speaker that sounds good solo will usually sound good in stereo.

think about that for a second. lets take the example of three identical,decent speakers for L,C and R.
play a phantom center out of the l and r and it could sound great. now route that same sound to the actual center and it could sound bad.imo, this is why the center speaker is of utmost importance in the home theater environnment.



.

From Dr. Toole's book of acoustics:

"In monophonic tests, listeners reported large differences in both sound quality and
spatial quality, and, if anything, there were stronger differentiations in the
spatial quality ratings. This was definitely not anticipated, but these listeners
had little doubt that there were substantial differences in both rating categories.
However, in stereo listening, most of the differences disappeared. The two highly
rated loudspeakers (AA and E) kept their high ratings, almost identically in fact,
but the loudspeaker (BB) that had a low rating in mono became competitive in
stereo. In fact, looking at the stereophonic data, the scatter diagrams of judgments
indicate a lot of indecision about the relative merits of these loudspeakers
in both categories: sound quality and spatial quality."

.
.


Comparison of Loudspeaker-Room Equalization Preference for Multichannel, Stereo, and Mono Reproductions: Are Listeners More Discriminating in Mono?


"In this experiment, a panel of trained listeners gave comparative preference ratings for three different loudspeaker equalizations based on anechoic and in situ measurements evaluated in a semi-reflective room, using three multichannel music recordings reproduced in surround, stereo, and mono. These equalizations were compared to the unequalized loudspeaker. The results are summarized as follows: all three equalizations were equally preferred over the unequalized system. The differences in preference ratings increased as the number of playback channels was reduced from 5 channels (surround) to 1 (mono). "

 
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B

big O

Junior Audioholic
no takers on mono discrimination?
 
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