Imaging/sound stage question

[thepogue]

II find that with my current room/set-up the "center" of my sound stage seems to move...what I mean is that with some LP's and CD's the center tends to be left...then the next LP it's dead on and on others it will be off to the right...I know that sounds very weird but I never had that happen (not at least to such a extent that it was a issue) using my "Box" type speakers...I normally just use my balance control to shift the sound stage to center as needed. Here's my thoughts and questions. Is the imaging so darned detailed on my Prodigy's that in my smallish room (12 x 13) that a "strength" has become a weakness in this room/set-up? OR after a couple of months, am I still not used to the way they present music. One more point I have a set-up disk and one test is that it allows you to pin-point the center by using a test tone that shifts for left, left center, center, right center and then right. (and back and forth quite a few times) when using this, my balance control needs to be in the 1 to 1:30 position to have center dead-on. Even when set, some LP/CD's tend to be off (some left and some right of center). Because of this I think it's a combination of me not being used to such accuracy and my room being overloaded and just doing wacky thangs... I also checked the amps and wires but because the overall volume seems to be the same (L/R) and it's more the imaging shifting I think that it's not a hardware issue (in that vain). Any thoughts? Just for the record, by this winter I'll have a 12 x 22 area which should do much better. Thanks, Pogue

[Florian]

I had the same problem with my Apogee's, and it turned out to be related to the room and positioning.

Try this:

Use a string and attach it to the center of your listening position and then use the string to make sure that your Prodigy's are at 100% the same distance and toe-in . Dont measure from the walls since they are mostly crooked. Try light soft damping behind the panels and the sides.

-Flo

[corwin99]

I've found some CDs just have the voice not dead center.. left of center tends to be really popular and sometimes right of center as well, and I've tested with several systems in different rooms to verify this. But based on your experience with the test CD it sounds like you have something else going on too. Just wanted to mention this.

[thepogue]

I'm just glad I'm not losing it..lol (well not ready to admit it anyways...lol)
I'll do the string thang tommorrow when I get off duty...see where I'm at.


Thanks, Pogue

[Feanor]

As you suggest yourself, prehaps the precission of the MLs; also their bi-polar nature might account for the problem. Bi-polars are very sensitive to reflections coming from the wall behind them. Try Florian's advice. The reflections as well as the direct sound will be contributing to the seeming imbalance. If reasonable measures don't work, set you balance at 1 o'clock or whatever measures center and generally leave it there.

Certainly it's true that many records seem "off balance" one way or the other. Ease your mind: just accept these recordings the way they are, i.e. the engineer wanted them that way for whatever reason.

[kexodusc]

Yep, a lot of factors at work here. Room acoustics can contribute to off-centered imaging, but the studio work of the recording could be slightly off as well.
Not a big deal though. Even in front row center, most performers I've seen play live tend to move several inches, sometimes a few feet off dead-center, so I think it's to be expected.

[RGA]

One reason most amplifiers have a balance control.

[nightflier]

I am currently comparing two very different amplifiers (a B&K Ref.4420 and a PS Audio HCA-2), and the soundstaging is very different. I am keeping all other components, cables, and speakers the same and just switching out the amps, but the differences are quite noticeable.

On one of my better test tracks (Rush - Moving Pictures - Witch Hunt), Peart's drumbs sound further to the left with the HCA-2. The bells at the beginning are so close I feel I can touch them, but with the B&K they are further away and so appear to be more centered. Lee's voice is also about a foot further to the left with the HCA-2, something I cannot cleanly correct with the balance control.

Another track I use is Take Five (Time Out - Dave Brubeck). The drum starts off on the far left, and then Brubeck starts playing the keyboards on the right. When the main theme chimes in, it's supposed to be about two feet to the left of center (at least that's where I expect it). The HCA throws that futher to the left, though, about 3 feet off center. The B&K on the other hand, brings it back to where I expect it, but it's further back. The HCA-2 also sounds more airy and little less precise, so my measurements maybe a tad off.

Maybe depth is another factor in where the instruments and vocalists appear in front of you?

[BluesKaj]

Sometimes it's just the way the furnishings in the room affect the sound at various frequencies. The center image isn't what it's cracked up to be no matter what you may read in the audio mags and advice columns, Don't sweat it too much cuz the recording studio engineers don't worry about the center image as much as most audiophiles do.They normally use nearfield monitors on the final mixdown and place or image the instruments and vocals according to studio acoustics. We forget how mundane it can be at the source. :rolleyes:

[PAT.P]

Yep, a lot of factors at work here. Room acoustics can contribute to off-centered imaging, but the studio work of the recording could be slightly off as well.
Not a big deal though. Even in front row center, most performers I've seen play live tend to move several inches, sometimes a few feet off dead-center, so I think it's to be expected.
Kexodusc I read a article on Accoustics in a larger scale (auditorium) at www.lenardaudio.com in their Education section.It also talks about speaker cross-over what to look for in a good speaker .Thaught it would be .I certainly put it in my favorite section on my computer.Know I would like a four way speaker like they built.Pat.P

[kexodusc]

Pat:

Lots of good info there...I'm not sure I agree with their opinion that a 4-way design is optimal. It contradicts their 3 Laws of Crossovers:
1. It is not possible to stitch 2 different speakers together, perfectly.
2. A crossover should have the minimalist complexity, to achieve the desired outcome.
3. The more complex a crossover, the more difficult the system is to control.

There is an aweful amount of complexity involved just in level matching 4 speakers together in a crossover. I think the problem comes from their assumption that speakers should disperse sound evenly at all frequencies.
In the home, I'd argue that this isn't necessary at all. Higher frequency sourses aren't widely dispersed in music anyway. Most of us sit in (or near) a sweet spot and that can be good enough.
For much larger venues though, wider dispersion is certainly an asset.

[Pat D]

II find that with my current room/set-up the "center" of my sound stage seems to move...what I mean is that with some LP's and CD's the center tends to be left...then the next LP it's dead on and on others it will be off to the right...I know that sounds very weird but I never had that happen (not at least to such a extent that it was a issue) using my "Box" type speakers...I normally just use my balance control to shift the sound stage to center as needed. Here's my thoughts and questions. Is the imaging so darned detailed on my Prodigy's that in my smallish room (12 x 13) that a "strength" has become a weakness in this room/set-up? OR after a couple of months, am I still not used to the way they present music. One more point I have a set-up disk and one test is that it allows you to pin-point the center by using a test tone that shifts for left, left center, center, right center and then right. (and back and forth quite a few times) when using this, my balance control needs to be in the 1 to 1:30 position to have center dead-on. Even when set, some LP/CD's tend to be off (some left and some right of center). Because of this I think it's a combination of me not being used to such accuracy and my room being overloaded and just doing wacky thangs... I also checked the amps and wires but because the overall volume seems to be the same (L/R) and it's more the imaging shifting I think that it's not a hardware issue (in that vain). Any thoughts? Just for the record, by this winter I'll have a 12 x 22 area which should do much better. Thanks, Pogue


I had both forward radiating box speakers and electrostatics (though not hybrids) so I have some experience with the differences.

As others have noted, two main causes of channel balance problems are 1) the recordings themselves--and you often can't do much about that except adust the balance, and 2) the room acoustics and speaker placement.

Since you seem to have eliminated the electronics, I suggest you also eliminate the speakers. I suggest switching the left and right speakers to see if the image changes much. It is possible that is part of the problem and it is good method to check this out.

My hypothesis in such matters is that if the response from both channels at the listening position is not about the same, for whatever reason, then the image can be affected differently depending on the frequency content of various recordings. For example, if there are a lot of upper strings on a recording and one speaker has more output in that range than the other, then the image will be pulled over that way. With other recordings which don't have much content in that range, the image will be different. That kind of thing.

Dipoles don't have any output straight out to the sides, which simplifies placement in some respects, and they tend to be somewhat directional--your prodigies have wider dispersion than most ESLs judging from the Stereophile review. Still you have to take account of the first reflections off the side walls or whatever is there to ensure the frequency balance is similar for both channels.

Dipoles also radiate to the rear--in the opposite polarity to the front wave, which is why the output to the sides is canceled out. So you have to take account of what is behind the speakers, too.

As you have noted, with well set up forward radiating speakers, the channel balance is not usually much of an issue. It should be the same with dipole speakers.

I think you will probably be happier with your Prodigies when you can put them in the larger room. I know my Quads needed to be about 4 feet from the rear wall.

[theaudiohobby]

Sometimes it's just the way the furnishings in the room affect the sound at various frequencies. The center image isn't what it's cracked up to be no matter what you may read in the audio mags and advice columns, Don't sweat it too much cuz the recording studio engineers don't worry about the center image as much as most audiophiles do.They normally use nearfield monitors on the final mixdown and place or image the instruments and vocals according to studio acoustics. We forget how mundane it can be at the source. :rolleyes:
Some of absolute best imaging performance I have heard have been from studio monitors. the image was rock solid, tonality and timbre in the listening window was spot on, if timbre and tonality are really right, then image and soundstage simply falls into place as a matter of course.

[RGA]

if timbre and tonality are really right, then image and soundstage simply falls into place as a matter of course.

:rolleyes:

[thepogue]

kinda' blood shed here...:D Pogue



:rolleyes:

[kexodusc]

Some of absolute best imaging performance I have heard have been from studio monitors. the image was rock solid, tonality and timbre in the listening window was spot on, if timbre and tonality are really right, then image and soundstage simply falls into place as a matter of course.

Hmm, this is one area I might respectfully disagree with you on. I' have a pair of mid size standmount speakers that have great timbre/tonality, and really reproduce the detail well, but the imagery and holographic reproduction were quite poor. Actally the center image is so concentrated and focused it sounds too "processed" or fake. Not lifelike. They were delegated to nearfield monitors and did quite well at this task because the image deteriorated some. But they do fail to create a soundstage outside the speakers width, and have less "depth" to them. Not very good outside my small computer room.

I've also heard the opposite. I've purchased speakers that were very inexpensive, but had every component tolerance matched to the other. The tonality was quite mediocre but the presentation was very good for the money.

[nightflier]

Hmm, this is one area I might respectfully disagree with you on. I' have a pair of mid size standmount speakers that have great timbre/tonality, and really reproduce the detail well, but the imagery and holographic reproduction were quite poor. Actally the center image is so concentrated and focused it sounds too "processed" or fake. Not lifelike. They were delegated to nearfield monitors and did quite well at this task because the image deteriorated some. But they do fail to create a soundstage outside the speakers width, and have less "depth" to them. Not very good outside my small computer room.

I've also heard the opposite. I've purchased speakers that were very inexpensive, but had every component tolerance matched to the other. The tonality was quite mediocre but the presentation was very good for the money.

When I was auditioning studio monitors, I noticed a marked difference between various brands and models. Some are made to excel in each area, too, so a blanket statement about monitors can't be made like that. After about three hours of bugging the sales rep (who eventually parked himself behind the rack rather than come back around each time), I settled on a pair that I thought were the most accurate to the music but were also able to reproduce the imagaing and depth as acurately as possible. The last pair I considered before these were a pair of Dynes that seemed at times to fare better in this area, but they were not nearly as accurate and detailed.

I settled on the Event Studio Precision 8s, a remarkable speaker that is now my benchmark for everything else. True, they are not terribly pleasant to listen to for long periods, but they are about as accurate as I have ever heard and do an excellent job in all other areas as well.

I should mention that when auditioning, the speakers were closer together and not toed in. I now have them in my listening room, further appart, toed in and connected to a small pre (they each have two seperate built-in amps, one for the tweeter and one for the woofer). I wish I had selected the passive speakers however, because to compare, I always have to use a seperate amp with other speakers. So I will never know if the improvement is strictly because of the speakers or because of the amps. But if you want to find out if your source is accurate and centered, there is no better way to do this than with a pair of studio monitors.

[Geoffcin]

I am currently comparing two very different amplifiers (a B&K Ref.4420 and a PS Audio HCA-2), and the soundstaging is very different. I am keeping all other components, cables, and speakers the same and just switching out the amps, but the differences are quite noticeable.

On one of my better test tracks (Rush - Moving Pictures - Witch Hunt), Peart's drumbs sound further to the left with the HCA-2. The bells at the beginning are so close I feel I can touch them, but with the B&K they are further away and so appear to be more centered. Lee's voice is also about a foot further to the left with the HCA-2, something I cannot cleanly correct with the balance control.

Another track I use is Take Five (Time Out - Dave Brubeck). The drum starts off on the far left, and then Brubeck starts playing the keyboards on the right. When the main theme chimes in, it's supposed to be about two feet to the left of center (at least that's where I expect it). The HCA throws that futher to the left, though, about 3 feet off center. The B&K on the other hand, brings it back to where I expect it, but it's further back. The HCA-2 also sounds more airy and little less precise, so my measurements maybe a tad off.

Maybe depth is another factor in where the instruments and vocalists appear in front of you?

Along with a much more "up front" presentation from the PS Audio HCA-2 amp. I can conferm these obervations for you with my own. The B&K while obviously a good amp, does not have the ability to seperate the soundfield as much as the PS Audio amp. This is why it's presentation is narrower, and further back. As for "airyness"; People go to great lenghts to get this from their setups, if your hearing this from your setup, you in good company.