"The Imaging and Sound Staging ..........

[mah]

......is excellent". Whenever I see this comment applied to audio devices I think, "compared to what"?

Can anyone enlighten me?

Marshall.

[selmerdave]

I guess you have to experience it. When you listen to a setup and you hear a vocalist 7' in front of you, a bass player 4' behind the vocalist and 1' to the right, a piano player 6' to the left of the bass player and a drummer right behind the bass and piano with no sound (seemingly) coming from the speakers, you'd probably say something similar. You need a good amp to get it, as well as perfectly placed (literally within an inch) speakers and listening chair. It's a specific type of audio experience that is quite addicting.

604's and M19's are capable of some fantastic imaging.

Dave

[bfish]

Originally posted by mah:
..."compared to what"?

<font size="2" face="Verdana, Helvetica, sans-serif">Theoretically? A mono point source.
Practically? The last system you owned/listened to.

Personally, I think the recording technique has as much or more overall effect in creating a convincing soundstage as the playback system. With the possible exception of the old binaural methods, a convincing effect is all it is, with perceived localization having little or nothing to do with the actual location/placement of the individuals as they were recorded. Consider the numerous recordings where some or all of the elements were recorded in isolated rooms or booths, yet the finished product creates an entirely different illusion upon stereo playback. Entertaining? Yes. Accurate duplication of the original? Not so much.

Still, great importance is placed on localization attributes of playback systems. Some judging criterion from a car stereo competition form;

Sound Staging (25 pts ea);
Perceived Width
Perceived Depth
Perceived Height

Imaging (15 pts ea);
Image Placement ? Left
Image Placement ? Left Center
Image Placement ? Center
Image Placement ? Right Center
Image Placement ? Right
Size of Virtual Sound Images
Holographic Presentation

I've encountered instances where the apparrent width and depth greatly exceeded that of the listening room. The only way I could enjoy it was to close my eyes.

Sometimes, the effect can be really annoying, like when I go to the door or reach for my cellphone when the ringing was on some stupid commercial...I can't remember what song, but I used to have an 8 track tape in the car that had me pulling over on the shoulder when a siren approached from behind.

[selmerdave]

Well I don't think you'd want to listen to a band effectively portrayed in booths.

Before too much negative connotation gets attached to something like the term "effect", we should remind ourselves that the whole playback process is creating an illusion or effect. Recorded sound is a very bad approximation of live sound but it can create a relatively effective illusion of live sound. Same with the soundstaging. Sounstaging is generally poorly implemented these days (ie. stereo drumset or stereo piano), when done well it makes the music seem that much more real to me.

I would respectfully disagree with bfish about the recording process being the most significant, while it can only happen when it is designed to happen from the recording process I have never heard an okay system do even a mediocre job of it. For example my Klipsch Heresy's will image great with my SET amp, yet the same recording through the same speakers and my Technics receiver gives no image whatsoever. Yes, left is left and right is right, but no image. I would consider it an excellent test of the quality of a system.

The best imaging records that I have are Sheffield Labs direct to discs done with a single AKG C-24.

Dave

<font color="#FFFFFF"><font size="1">[ July 18, 2008 01:35 AM: Message edited by: selmerdave ]</font></font>

<font color="#FFFFFF" size="1">[ July 18, 2008 01:36 AM: Message edited by: selmerdave ]</font>

[bfish]

Originally posted by selmerdave:
...I would respectfully disagree with bfish about the recording process being the most significant...

<font size="2" face="Verdana, Helvetica, sans-serif">Then how come...

Originally posted by selmerdave:
...The best imaging records that I have are Sheffield Labs direct to discs done with a single AKG C-24.

<font size="2" face="Verdana, Helvetica, sans-serif">?????

Actually, I said "as much or more"... though I realize my habit of carrying a fire hose instead of fanning the flames of passion can lead to presumptions. That's cool, just don't rule out the possibility of me surprising you sometime.

Marshall, in my typical style, it might appear that I lumped imaging in on my "scoff list". Not the case. It's a very real and satisfying effect, and definitely worthy of pursuit. What I do laugh at sometimes, is the occasional gushing attempt to (over)rate it, done by the same folks that experience overtly verbous oargasms over a good hotdog. There's simply no comparison to being front and center at an orchestra performance and achieving a soundstage in your living room.

There are a couple of things I've found that one can do to improve imaging, eliminate (the largely ignored) component crosstalk (something a pair of monoblocks excell at), and maximize overall symmetry and balance (including the listening environment). The best engineered recording falls to pieces when signal bleeds between channels, or the channels are unequal in any parameter. I'll bet Dave's Technics receiver either has excessive crosstalk (most likely) or unmatched channels. A good amp won't kill imaging, no matter the type. An easy measure of both parameters can be had in the freeware RMAA and a simple loop test of the suspect component(s).

Imaging also seems to depend to a large degree on how well your speakers approximate point sources. In the case of A7s, this means you'll need to be a considerable distance from them for imaging to occur. If you can identify the LF and HF sources as being located separately, either they're too big or you're too close. Either way, they won't image well.

[mah]

Dave,

I still ask "compared to what"? I am not refuting that a reproducing system will present a representation of a soundstage. I just do not understand how the quality of this reproduction can be assessed without reference to the source.

Regards, Marshall.

[selmerdave]

Originally posted by bfish:
</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by selmerdave:
[qb]...I would respectfully disagree with bfish about the recording process being the most significant...

<font size="2" face="Verdana, Helvetica, sans-serif">Then how come...

Originally posted by selmerdave:
...The best imaging records that I have are Sheffield Labs direct to discs done with a single AKG C-24.

<font size="2" face="Verdana, Helvetica, sans-serif">?????</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Well it's all in the rest of my sentence..

"while it can only happen when it is designed to happen from the recording process I have never heard an okay system do even a mediocre job of it."

In other words, yes the recording is very important but on all but very good setups those Sheffield recordings won't image worth a darn. In addition, on a good setup any recording will produce some kind of image. Whether it is the type of image that suits one's taste or idea of "real" will depend on how it was done in the studio. You can't reproduce an image without a good and proper setup regardless of the recording process. Of course you can argue the reverse and I'm not here to say my opinion is better than yours, just contrary to yours.

I hope disagreement does not equal flaming, I would like to think that we are here for discussion. Perhaps I am coming across as more heated than I intend, I hope not.

I'd also disagree about the monoblock/crosstalk thing, an image needs a signal to be in both channels or else it will just seem to come directly from one speaker, so whether there is a small amount of crosstalk or not shouldn't affect that terribly. FWIW my stereo amp images better than my monoblocks. It was also a trick years ago to add crosstalk to heighten imaging, although that's not so fashionable now (but I've heard it works). Obviously we're not talking about an amount of crosstalk that approaches mono.

Not related to that, mono playback through a stereo set of speakers should produce a good image albeit entirely centered.

Dave

<font color="#FFFFFF" size="1">[ July 18, 2008 11:30 AM: Message edited by: selmerdave ]</font>

[selmerdave]

Originally posted by mah:
Dave,

I still ask "compared to what"? I am not refuting that a reproducing system will present a representation of a soundstage. I just do not understand how the quality of this reproduction can be assessed without reference to the source.

Regards, Marshall.

<font size="2" face="Verdana, Helvetica, sans-serif">The short answer is it's in comparison to a system that does not produce an image. It's not so much about guessing whether the image that seems 20' wide and 40' deep matches the dimensions of the recording room. The point is with that recording some systems will portray sound coming from a pair of speakers and other systems will portray a room that is 20' x 40' with a number of musicians in various places and no speakers to be heard.

Dave

<font color="#FFFFFF" size="1">[ July 18, 2008 11:38 AM: Message edited by: selmerdave ]</font>

[mah]

Bfish,

Bull's-eye.

No doubt about a spatial effect being heard to various degrees on different recordings.

It appears that what people hear as imaging can only be critically assessed in comparison with the original recording and play-back process, and environment.

Too bad the effect lends itself to Hocus Pocus in some professions.

Cheers

[bfish]

"I hope disagreement does not equal flaming"...

Certainly not for me Dave, it keeps things interesting. I figured we've done enough poking by now that one of the other pigs would have squealed. Guess they're all just fat, old, and indifferent...

Some searching on the topic turned up lots of AES papers, and after a little due diligence, I finally found one online in its' entirety. 76 interseting pages by D.B. Keele and T.M. Bock. Haven't finished reading it yet, it's more than I could digest at once;



Drat! After all that, Hostboard won't let me post the link because it contains parentheses...I managed to get it in as above, but you'll need to omit the first 5 and the last 7 characters of the string. Pseudo intuitive, start with http and end with pdf. What a pain...