Vertical location of instruments

Okay, it's time once again to expose my ignorance (or, positively spun, my curiosity).

From the start, I noticed that instruments (particularly those located to the left or right side of the soundstage) did not all appear to emanate from the same height on my Summit panels. In fact, the difference can be quite dramatic. It is obvious enough how an instrument is located horizontally (that is, by the relative balance of the L/R signals), but how does it happen that some sounds appear to come from high in the panel, others low, others middle? I haven't noted any consistency, e.g., at particular frequencies. The effect is unmistakable, however. It's not at all unpleasant, but I wonder what is going on.

CCH said:

Okay, it's time once again to expose my ignorance (or, positively spun, my curiosity).

From the start, I noticed that instruments (particularly those located to the left or right side of the soundstage) did not all appear to emanate from the same height on my Summit panels. In fact, the difference can be quite dramatic. It is obvious enough how an instrument is located horizontally (that is, by the relative balance of the L/R signals), but how does it happen that some sounds appear to come from high in the panel, others low, others middle? I haven't noted any consistency, e.g., at particular frequencies. The effect is unmistakable, however. It's not at all unpleasant, but I wonder what is going on.

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Hola, I think your ears are tricking you. If you want to test the panels, play a pink noise (like the broadcast FM signal without station, a ssssssshhhhhhh) and listen if all the panel sounds the same. If you have portions of the panel that it is not sounding the same, it is time to give them a good shower...go to tweak section of this forum, you will find this info there. Or, you can contact Jim Power at ML. He will guide you step by step. Happy listening and trust your ears...
Robertol

Thanks for the reply. Actually, the panels are relatively new and fairly clean, and I have tried the pink noise test. (I've tried a few other things, like reversing phase, reversing balance, switching back and forth from stereo to mono, etc.) It is only on some (actually, quite a few) recordings that I will hear one instrument higher in the soundstage than another. The effect is consistent and rather remarkable. It could well be caused by differing reflections at different frequencies, but I've discounted this explanation somewhat since, for example, a cymbal on two different recordings can be located at two very different heights. I have to say that is is seldom a problem sonically. In fact, it often makes the recording more interesting, since the soundstage is that much more complex/layered (height as well as width and depth variations). It's more a curiosity, something I would like to understand but don't.

Hi CCH,

Have no idea what Roberto is talking about.

This happens all the time on my system and the other 3 ML models I've had.

The suspects are likely to be the recording, how the engineer mixed it, your equipment, your speaker setup, and of course, the room.

Best example is a symphony orchestra.

Strings are generally at the lower portion of the sound stage, winds in the middle, and brass higher up, which is consistent with what you would hear in a live concert.

GG

Maybe you both get the same type of Mushrooms on your pizza

Very funny repman.

Didn't somebody, I think Chesky, on a 2-channel demo do a height demonstration recording?? Yes I know they do a distance demo, but I think I remember height too. Maybe?

I think that I've seen discussion somewhere that when phase is kept very true that you can get some height information from some mic techniques.

Maybe somebody else wlll remember some other titbits on this.

CoolJazz

can i have the number of the pizza joint?:ROFL:

Jimna said:

can i have the number of the pizza joint?:ROFL:

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most likely only you will appreciate this its VINCENTS ( Vinny pie):drool:

Gordon Gray said:

Hi CCH,

This happens all the time on my system and the other 3 ML models I've had.

The suspects are likely to be the recording, how the engineer mixed it, your equipment, your speaker setup, and of course, the room.

GG

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Hi CCH,
Gordon is right... The official position - and people will queue up to tell you - is that no height information is embedded in a stereo recording. While this may be true, it doesn't prevent loudspeakers (and particularly panel speakers) giving a clear height representation!
I noticed recently while listening to the Beach Boys "Endless Summer" album that the tracks divided into groups. Those perhaps recorded in a certain studio or in a certain way ended up with vocals at consistent heights in both L+R channels, but there were the odd exceptions which showed clear L/R differences i.e L top of panel, R almost at floor level.

Now ask anyone, your neighbour, your wife, or your dog, to describe those instrument or vocal heights without prompting and, to a man - or canine, they will give you exactly the same locations for them.

Spooky....is it not...

You are not mad..and your speakers are not malfunctioning
Best regards..............Victor

Thanks, Victor. Like you say, I am certain that what I am hearing is really there and, moreover, that others who listen hear the same thing. I just didn't expect it. It is a bit spooky--but nice!

I have oddyseys - not summits - but, it is my impression - maybe incorrectly - that if I put my ear up to the panel - and slowly raised from the bottom - to the top - that each section of the panel seemed to sound different - with the higher frequencies at the very top of the panel - the mids -centric - and the lower mids at the base of the panel... Maybe I too have had the mushrooms?? or maybe it isn't the panel - but the proximity of the woofer as I do this?

timm said:

I have oddyseys - not summits - but, it is my impression - maybe incorrectly - that if I put my ear up to the panel - and slowly raised from the bottom - to the top - that each section of the panel seemed to sound different - with the higher frequencies at the very top of the panel - the mids -centric - and the lower mids at the base of the panel... Maybe I too have had the mushrooms?? or maybe it isn't the panel - but the proximity of the woofer as I do this?

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A bit of both actually.

The panel segmentation does cause each 'segment' to have different resonant frequencies, with the smaller 'segments' tuned to higher frequencies.

And of course, the closer to you get to the woofer, the more those frequencies blend in to the overall sound.

This effect of hearing distinct height positioning of certain instruments is a complex combination of factors that a large dipole will exhibit more than a small point-source speaker.

First, the interaction of the rear wave of the dipole with the room. In models where the panel leans back a little (most current models), there are possible reflection paths that can come back to the listener via a ceiling bounce, which would raise the apparent soundstage for the particular frequency band being reflected (reflections are often seriously attenuated at varying frequencies).

Second, the cross-channel phase information in the recording, combined with the fact that there is a lot of in-room cross-channel information from the complex rear have horizontal dispersion paths will occasionally combine to 'steer' sounds a lot harder than when listened to on monopoint speakers.
This lateral steering, combined with jsut the right celingin and floor bounce reflections will 'pull' certain frequencies at certain pahse angles to appear higher and/or wider than one would expect.

Its a great attribute of large dipole line sources that they can pull of this illusion, but it is very circumstantial.

I personally find I like the more predictable and controllable dispersion/reflection characteristics of the original ML line with their perpendicular and larger (in height) panels.

I also find that actively managing the rear wave results in a very large and wide soundstage. Much better than random reflections, but I do lose some of the occasional height effect on certain recordings.
The trade-off is worth it, as I prefer a more accurate, predictable soundstage for the multichannel audio I mostly listen to.

There is at least one test CD that contains a track specifically for demonstrating vertical heights in a stereo setup. The test track reproduces sound that moves from one speaker to the other but doesn't just move from left to right. It moves up and then back down as the sound travels from one speaker to the other.

It also contains tracks for testing phase, left right channels, mono compared to stereo and a few other tracks useful for basic set up and testing of your stereo.

Sleepysurf has this disk and probably tell us more about this particular test CD or which one it is.

Just throwing this into the mix of information already provided.

I recently replaced the tubes in my amp, they are still breaking in (only a dozen hours on them so far). I can say that the sound-stage and placement of instruments per the frequency has definitely changed. I am still lacking the full front to back depth at this stage of tube break-in and the very top end sparkle is still a little muted. However the up and down placement is much more solid. So much so that the shelf of sound on top of the big TV in between the speakers where the vocals would seem to appear is no longer there. The vocals are now complete (top and bottom) and slightly in front of the speakers.

I am providing this example to illustrate that the amplifier can and will affect placement of instruments (R/L & T/B). The recording can do this same shift as well as the speaker "segments" making a contribution, in my opinion.

JonFo said:

This effect of hearing distinct height positioning of certain instruments is a complex combination of factors that a large dipole will exhibit more than a small point-source speaker.

First, the interaction of the rear wave of the dipole with the room. In models where the panel leans back a little (most current models), there are possible reflection paths that can come back to the listener via a ceiling bounce, which would raise the apparent soundstage for the particular frequency band being reflected (reflections are often seriously attenuated at varying frequencies).

Second, the cross-channel phase information in the recording, combined with the fact that there is a lot of in-room cross-channel information from the complex rear have horizontal dispersion paths will occasionally combine to 'steer' sounds a lot harder than when listened to on monopoint speakers.
This lateral steering, combined with jsut the right celingin and floor bounce reflections will 'pull' certain frequencies at certain pahse angles to appear higher and/or wider than one would expect.

Its a great attribute of large dipole line sources that they can pull of this illusion, but it is very circumstantial.

I personally find I like the more predictable and controllable dispersion/reflection characteristics of the original ML line with their perpendicular and larger (in height) panels.

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Jonathan...you have clearly thought about this ! I think this qualifies as the best explanation of the phenomenon that I've ever seen !!

The height results I've had with my own setup have surprised me in the past given that the rear wave was always damped by curtains (although not the full width of beam so there may have been "fringe" effects - but the space between the curtains was always partially damped/dispersed by closed vertical blinds to avoid reflection from windows.)
In line with what you've said, I remember Roberto mentioning a while ago, shortly after the introduction of the new series, that accentuating the rake angle of the panels could be conducive to enhancing height information?

In truth, the angle need only be slight (mine are only a few degrees behind vertical)
What I find remarkable about the illusion is it's consistency and coherence given the relative volumes of different voices/instruments. I tend to liken it to an architect's drawing, with construction lines which disappear to vanishing point centre stage. As a sound appears further back in the stage so its height appears reduced i.e. the closer/louder the singers are, the taller they get. Once accustomed to this effect it is hard to imagine reverting to a more planar presentation of the stage.

Craig said:

There is at least one test CD that contains a track specifically for demonstrating vertical heights in a stereo setup. The test track reproduces sound that moves from one speaker to the other but doesn't just move from left to right. It moves up and then back down as the sound travels from one speaker to the other.

It also contains tracks for testing phase, left right channels, mono compared to stereo and a few other tracks useful for basic set up and testing of your stereo.

Sleepysurf has this disk and probably tell us more about this particular test CD or which one it is.

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I have the XLO/Reference Recordings test disc and if I recall correctly (in fact I am 99% certain) one of the tests is just that.

CCH: It sounds like you've tried several things already, but have you tried systematically playing with the tilt of the speaker? Even tiny differences of tilt can make a surprising difference to where the height of an instrument appears to come from (as Jonathan explained the reasons for).

Tosh said:

CCH: It sounds like you've tried several things already, but have you tried systematically playing with the tilt of the speaker? Even tiny differences of tilt can make a surprising difference to where the height of an instrument appears to come from (as Jonathan explained the reasons for).

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I have played with the rake angle from time to time, but I always come back to the current setting. I wasn't paying attention to the location of particular instruments in the process. When I get the chance, I'll experiment with it and see what happens. I should say that I actually like the way the vertical location of instruments varies. It rarely sounds artificial or unpleasant and usually adds an interesting dimension to the sound (just as differences in depth and width enhance the presentation). I'm not trying to get rid of the phenomenon, but I do want to understand it. I have learned from this thread and appreciate all of the informative responses. Thanks!