interaural effect on some records

leftwinger57

Dudes you know I have a fairly simple mind and I kinda grasp the concept of the inter aural effect w/ SDA speakers. Proof of point 2 fine examples would be both from the Stones Wild Horses where you hear acoustic guitars on the left, vocals piano and rhythm on the right. Another great would be Angie. Both recorded I believe on 16 track recorders of the day. Now come Jimi and his engineer Eddie Kramer w/ Axis Bold As Love and towards the end you clearly hear Mitch Mitchel's drums phasing from one side to another and then Jimi does basically the same thing. Both were recorded long before SDA was invented so does this inter aural effect pick and choose when it comes to play or the engineers intended on this is how it should be heard.

pitdogg2

Stones i bet were original mono recordings as that was the way they recorded mono.

Jimi is nothing more then the engineer sliding a knob left to right or right to left.
As for SDA its always there but there are recordings that really shine with SDA's then again there are some that are just ****.

leftwinger57

I got what your saying w/ the engineer shifting knobs and levers to phase the sound .Personally I think your way off base thinking in 69/71 that Sticky Fingers was recorded in mono. It was made w/ an 18 track machine in Muscle Shoals. We're not talking '66 here.

http://www.songfacts.com/detail.php?id=530

Emlyn

Rolling Stones albums released up through 1969 were recorded to be released in the mono format.

SDA is not an effect, it is a physical acoustic design to basically cancel interaural crosstalk and enhance stereo recordings to reproduce stereo more accurately than standard speakers.

Multi track recording capability existed long before stereo albums replaced mono albums as standard because most people continued to have mono playback systems into the late 1960s.

Early stereo albums that were mainly intended to be released in mono could sound really bad in comparison because they were forcing individual instruments into one channel. Real music does not sound like that. Most of the Beatles albums released in stereo were like that and I won't listen to them other than as a novelty.

If you are hearing something weird in a stereo recording on SDAs it is because of the sound engineer's deliberate choices in forcing instruments or voices to one corner and panning them from side to side the 1960s and into the 1970s were still experimental times with stereo. If you hear drums in the bottom of the right speaker and acoustic guitar hard panned to the left it is because the music was released that way. SDA would be more likely to accentuate the choices of the sound engineer, whether in mono or stereo, but since it is an always on physical thing SDA speakers just present what is presented to them from the recording.

pitdogg2

I'm not off base. Emlyn hit it right there. Even though they are stereo they still recorded and mastered mono like recording. Bass and drums on one side vocals and guitar's on the other side or vice versa. Some early stereo recording are horribly mono like. They really had no idea how to set up mic's to get the best effect and lets not forget stereo at first was 3 channel left, right and center.

K_M

Emlyn wrote: »

Rolling Stones albums released up through 1969 were recorded to be released in the mono format.

SDA is not an effect, it is a physical acoustic design to basically cancel interaural crosstalk and enhance stereo recordings to reproduce stereo more accurately than standard speakers.

In theory that sounds like the idea, except recordings are already made with that compensated for.
So it creates simply a wider than normal stereo image.

Unless the recording was mixed and mastered on SDA, it is actually creating a much less accurate sound in the end.

We own a couple pairs, and while it is pleasant and enjoyable, it is obviously artifical, and only works if the recording was Intended to be played back ON SDA speakers.

Stew

K_M wrote: »

Emlyn wrote: »

Rolling Stones albums released up through 1969 were recorded to be released in the mono format.

SDA is not an effect, it is a physical acoustic design to basically cancel interaural crosstalk and enhance stereo recordings to reproduce stereo more accurately than standard speakers.

In theory that sounds like the idea, except recordings are already made with that compensated for.
So it creates simply a wider than normal stereo image.

Unless the recording was mixed and mastered on SDA, it is actually creating a much less accurate sound in the end.

We own a couple pairs, and while it is pleasant and enjoyable, it is obviously artifical, and only works if the recording was Intended to be played back ON SDA speakers.

Recordings do not compensate for interaural crosstalk, with the rare exception of specialized binaural recordings. There are no recordings that were "intended to be played back on SDA speakers." That doesn't even make sense. Exactly the opposite. SDA's were designed to play normal stereo recordings more accurately. Reread Emlyn's post or read the SDA handbook. Are you just making this stuff up to stir the pot?

Stew

For the sake of accuracy and refreshing my memory , I did a quick read on binaural recrodings. I forgot they only work with headphones because --- stereo speakers add interaural crosstalk. So someone please correct me if I'm wrong but there are no recordings that cancel interaural crosstalk on stereo speakers. That leaves electronics or SDA.

I was enjoying this thread. People wanting to learn about SDA. People who appreciate SDA. If it's not for you so be it but why bash it? And please keep the discussion honest.

K_M

Stew wrote: »

K_M wrote: »

Emlyn wrote: »

Rolling Stones albums released up through 1969 were recorded to be released in the mono format.

SDA is not an effect, it is a physical acoustic design to basically cancel interaural crosstalk and enhance stereo recordings to reproduce stereo more accurately than standard speakers.

In theory that sounds like the idea, except recordings are already made with that compensated for.
So it creates simply a wider than normal stereo image.

Unless the recording was mixed and mastered on SDA, it is actually creating a much less accurate sound in the end.

We own a couple pairs, and while it is pleasant and enjoyable, it is obviously artifical, and only works if the recording was Intended to be played back ON SDA speakers.

Recordings do not compensate for interaural crosstalk, with the rare exception of specialized binaural recordings. There are no recordings that were "intended to be played back on SDA speakers." That doesn't even make sense. Exactly the opposite. SDA's were designed to play normal stereo recordings more accurately. Reread Emlyn's post or read the SDA handbook. Are you just making this stuff up to stir the pot?

We went over this before.

It is very simple, if you try to understand.
"Interaural crosstalk" is accounted for when mixing and mastering are done, not INTENTIONALLY, but simply as part of the process of a guy sitting there in the mixing or mastering room using a stereo pair of speakers (the engineer) and placing the sounds where HE wants in the left/right/center plane.

SDA artificially alters that intentional placement.

Ask any mixing or mastering engineer.

Emlyn

K_M wrote: »

We own a couple pairs, and while it is pleasant and enjoyable, it is obviously artifical, and only works if the recording was Intended to be played back ON SDA speakers.

No recording I'm aware of was specifically made to be played back on SDA speakers. SDA technology is simply stereo with some midrange crosstalk physically cancelled. If the speakers are used to play back a mono recording, the speakers will present a layered mono image between the speakers just like a well set up pair of conventional speakers would.

K_M

Stew wrote: »

For the sake of accuracy and refreshing my memory , I did a quick read on binaural recrodings. I forgot they only work with headphones because --- stereo speakers add interaural crosstalk. So someone please correct me if I'm wrong but there are no recordings that cancel interaural crosstalk on stereo speakers. That leaves electronics or SDA.

I was enjoying this thread. People wanting to learn about SDA. People who appreciate SDA. If it's not for you so be it but why bash it? And please keep the discussion honest.

No one is bashing It.
Did you read me saying I like the effect?

That does not make it accurate, but I enjoy it.

SDA effect is similar to headphones, far more than normal stereo sound.
Binaural recordings will work great on SDA.

Normal recordings do not CANCEL interaural crosstalk, but are mixed to place sounds where they sound correct with normal stereo speakers.

The SDA thing works IF the recording was done with 2 mics at about ear position, but in reality, that is very few recordings.

Stew

I understand what you're saying but unless the mixing engineer is trying to recreate a soundstage that is limited to the width between speakers with sounds localized from the speakers, I'm not buying it.

I do agree that some recordings move things to the extreme right or left in an attempt to compensate. Those recordings sound terrible on both normal stereo and SDA.

Again, if it's not for you so be it but why do you feel the need to try and convince people that they shouldn't like it either??

K_M

Stew wrote: »

I understand what you're saying but unless the mixing engineer is trying to recreate a soundstage that is limited to the width between speakers with sounds localized from the speakers, I'm not buying it.

I do agree that some recordings move things to the extreme right or left in an attempt to compensate. Those recordings sound terrible on both normal stereo and SDA.

Again, if it's not for you so be it but why do you feel the need to try and convince people that they shouldn't like it either??

I said I LIKE IT. I am not bashing it.
I am not trying to convince anyone of anything.
I said it is not accurate is all.

Soundstage is NOT limited to between normal speakers first off.
That may be partially why you are not understanding.

I have many times heard sounds from normal stereo speakers that "appear" to be several feet to the left or right of speakers.

I am not talking about far left or right placed sounds, but phase information can make sounds appear to come from beyond normal left and right speakers.

F1nut

K_M wrote: »

Emlyn wrote: »

Rolling Stones albums released up through 1969 were recorded to be released in the mono format.

SDA is not an effect, it is a physical acoustic design to basically cancel interaural crosstalk and enhance stereo recordings to reproduce stereo more accurately than standard speakers.

In theory that sounds like the idea, except recordings are already made with that compensated for.
So it creates simply a wider than normal stereo image.

Unless the recording was mixed and mastered on SDA, it is actually creating a much less accurate sound in the end.

We own a couple pairs, and while it is pleasant and enjoyable, it is obviously artifical, and only works if the recording was Intended to be played back ON SDA speakers.

This is nonsense.

K_M

We have had this discussion before on the forum, and in the end, realized many do not understand the recording/mixing/mastering process well enough, to realize why the SDA effect, as pleasant as it may be, is not accurate nor more than an effect.

I am not bashing it, but it simply is misunderstood by most, according to many of the replies in this thread and the other.

If recordings were made a certain way, (The way described by the old Polk sales literature, from back in the 80's) YES, it would create a more accurate soundstage and so on.

The issue, everyone is skirting around, it that virtually all recordings are not made in the manner that Polk describes, and in fact are multitrack recordings that intentionally place instruments in particular places intended FOR regular stereo speakers as a matter of fact.

If 2 microphones were place at head level the distance apart of our human ears, THEN YES it would be a valid way to create a more accurate soundstage, but that is not the case.

K_M

Polk SDA white paper:

"For example, suppose we go to a concert and put a microphone at each of our ears to record exactly what we are hearing.."

That is the assumption.
Recordings are not made in that manner though. Hardly ever. Binaural recordings are...but.
I think it speaks for itself.

The distance between SDA and Stereo drivers was chosen to emulate that mic spacing, same as the human head, mentioned in the SDA white paper, but they never address the fact that most recordings are not made in that manner.

F1nut

What we've got here is failure to communicate. Some women, you just can't reach.

Stew

K_M wrote: »

Polk SDA white paper:

"For example, suppose we go to a concert and put a microphone at each of our ears to record exactly what we are hearing.."

That is the assumption.
Recordings are not made in that manner though. Hardly ever. Binaural recordings are...but.
I think it speaks for itself.

The distance between SDA and Stereo drivers was chosen to emulate that mic spacing, same as the human head, mentioned in the SDA white paper, but they never address the fact that most recordings are not made in that manner.

K_M

Okay, so no one can discuss intelligently.
No surprise on this forum.

DarqueKnight

leftwinger57 wrote: »

Both were recorded long before SDA was invented so does this inter aural effect pick and choose when it comes to play or the engineers intended on this is how it should be heard.

SDA speakers do not produce an "effect". They greatly reduce a distortion inherent in the design of stereo speakers. It is actually conventional speakers that produce an "effect" of adding audible spatial distortion to the signal which interferes with sound localization.

K_M wrote: »

Polk SDA white paper:

"For example, suppose we go to a concert and put a microphone at each of our ears to record exactly what we are hearing.."

That is the assumption.
Recordings are not made in that manner though. Hardly ever. Binaural recordings are...but.
I think it speaks for itself.

The distance between SDA and Stereo drivers was chosen to emulate that mic spacing, same as the human head, mentioned in the SDA white paper, but they never address the fact that most recordings are not made in that manner.

You did not understand what the SDA white paper actually said. But first, let's review an earlier article on SDA technology. The original technical design overview for SDA loudspeakers was published in Audio Magazine in June of 1984. Here are some excerpts:

"Despite the fact that headphones [binaural loudspeakers] eliminate interaural cross-talk, they still do not usually produce a convincing stereo image." [Page 36, col. 2, par. 1, Audio Magazine June 1984]

"Although binaural recording techniques have produced startling results with headphones, our goal was to reproduce a more complete sound stage from existing stereo recordings." [Page 37, col. 1, par. 1, Audio Magazine June 1984]

Therefore, it would be quite silly for Polk to claim that binaural speakers usually don't produce a convincing stereo image and that they produce an incomplete sound stage, and then turn around and propose a "true stereo" loudspeaker design based on binaural recording techniques.

It is not correct to say that SDA is based on the assumption of binaural recording techniques. SDA technology is designed on the principle of interaural crosstalk cancellation based on the average distance between human ears:

"The placement of drivers shown in Fig. 10 also answered the requirement that the listening position be flexible. The center-to-center distance between the main and cancellation drivers on each side is the same as the distance between a person's ears, roughly 6-3/4 inches." [Page 38, col. 3, par. 3, Audio Magazine June 1984]

The statement you quoted from the SDA White Paper was part of a discussion that actually reiterated the sonic drawbacks of binaural recording and reproduction. The statement:

"For example, suppose we go to a concert and put a microphone at each of our ears to record exactly what we are hearing.." [Page 2, par. 2, SDA Surround Technology White Paper, 2005]

...was not intended to mean that SDA speakers are designed around the principle of binaural recording. It was intended, by example, to show that binaural recording and binaural playback does not produce a realistic stereo image. The complete story is as follows:

"For example, suppose we go to a concert and put a microphone at each of our ears to record exactly what we are hearing. Those recorded sounds contain all of the characteristics of the instruments and voices in the performance. But it is the differences between the sound recorded at our left ear, compared to what is recorded at our right ear, that contains all of the information about the positions of the instruments, the size of the concert hall, etc. Now we go home and play it back over a pair of stereo speakers. The sounds recorded at our left ear are played back from the left speaker and the sounds recorded at our right ear are played back from the right speaker. But what do we actually hear when we sit down to listen? Of course the sounds recorded at our left ear and played back through the left loudspeaker arrive at our left ear just the way they are supposed to. But there is nothing to prevent those same sounds from reaching our right ear also. In the same way, the sounds recorded at our right ear and played back over the right speaker arrive at our right ear but also cross over to reach the left ear. Instead of hearing just what was recorded at the concert, each of our ears also hears some of the sounds that were meant to be heard only by the other ear and vice versa. (See Fig. 1) Those extra sounds that cross to the opposite side of the head to reach the other ear are known as Interaural Crosstalk and they were not part of what you would have heard at the actual concert. The effect of IAC is to tell your brain where the loudspeakers are located while, at the same time, covering up the original recorded sound source location information. Once your brain knows where the loudspeakers are all of the sounds seem to come only from the loudspeaker locations and the space in between. This is nothing like what you heard at the original concert and is one of the major reasons why even the best conventional playback systems still don't quite sound like the real thing.
[Page 2, par. 3 to page 3, par. 1, SDA Surround Technology White Paper, 2005]

Reading further in the White Paper, similar to the Audio magazine article, it is explained that the spacing of stereo and dimensional (SDA) drivers is based on the distance between human ears, and not the spacing of binaural microphones.

"In contrast, SDA used a system of extra drive units placed at the same distance apart as the space between your ears (also known as the Interaural Distance) as the basis for an acoustic system of Interaural Crosstalk Cancellation. (See Fig. 2) The additional “SDA” drivers received an inverted version of the stereo signal from the opposite channel. [Page 4, par. 1, SDA Surround Technology White Paper, 2005]

For those interested in a more complete understanding of SDA design and function, a copy of the 2005 SDA White Paper and the 1984 Audio magazine article is attached.

K_M

@DarqueKnight
This is so simple.....

The "Crosstalk" you mention, is also heard by the Recording Engineer, so therefore, it is automatically compensated for with how he mixes the recording when he places the instruments and sounds within the final product.

F1nut

K_M wrote: »

@DarqueKnight
This is so simple.....

The "Crosstalk" you mention, is also heard by the Recording Engineer, so therefore, it is automatically compensated for with how he mixes the recording when he places the instruments and sounds within the final product.

This is why most here don't bother discussing this matter with you. You cannot seem to grasp what SDA does although it has been gone over time and time again.

DarqueKnight

@K_M

No, it is not simple at all.

In a previous thread in March of this year, I cited work by Dr. Floyd Toole that explained that interaural crosstalk (comb filtering) cannot be compensated for by recording techniques. Techniques such as using the pan pots to exaggerate the sound stage add an effect that was not in the original performance. No matter what tricks the recording engineer uses to manipulate the sound stage, the loudspeakers at the playback end will still produce interaural crosstalk.

The simple fact that you refuse to accept is that crosstalk cannot be compensated for in the recording process. A pair of conventional stereo loudspeakers will still produce four localization signals rather than the two that were produced by the original sound sources. The only way to compensate for crosstalk signals is to cancel them. There is no way to encode crosstalk cancellation signals in the original recording. This has to be done electronically or acoustically at the playback end.

If you actually read Matt Polk's 1984 paper, he provides an in-depth technical discussion of SDA design and operation principles and provides mathematical justifications.

K_M

F1nut wrote: »

K_M wrote: »

@DarqueKnight
This is so simple.....

The "Crosstalk" you mention, is also heard by the Recording Engineer, so therefore, it is automatically compensated for with how he mixes the recording when he places the instruments and sounds within the final product.

This is why most here don't bother discussing this matter with you. You cannot seem to grasp what SDA does although it has been gone over time and time again.

I know exactly what it "Claims" to do, but what it does in reality, is not exactly the same. (with most recordings)

Most recordings are made in a manner that is far different, than what they use as their example of a normal "Recording"

The "recording itself" does not compensate for crosstalk, but the Sound Engineer by using the same basic stereo 2 speaker set up we use at home, hears the same crosstalk we hear when he mixes and/or masters and bases his alterations to the soundstage to create the final product he deems correct.

Do you truly believe mixing engineers are creating something wrongly mixed, to their ears, in the hope that a few thousand people with Polk SDA speakers will be able to fix it with Polk SDA speakers??

Or do you think they assume most have normal 2 speaker stereo, and mix to make it sound just right with that set up?

F1nut

K_M wrote: »

F1nut wrote: »

K_M wrote: »

@DarqueKnight
This is so simple.....

The "Crosstalk" you mention, is also heard by the Recording Engineer, so therefore, it is automatically compensated for with how he mixes the recording when he places the instruments and sounds within the final product.

This is why most here don't bother discussing this matter with you. You cannot seem to grasp what SDA does although it has been gone over time and time again.

I know exactly what it "Claims" to do, but what it does in reality, is not exactly the same. (with most recordings)

Most recordings are made in a manner that is far different, than what they use as their example of a normal "Recording"

The "recording itself" does not compensate for crosstalk, but the Sound Engineer by using the same basic stereo 2 speaker set up we use at home, hears the same crosstalk we hear when he mixes and/or masters and bases his alterations to the soundstage to create the final product he deems correct.

Do you truly believe mixing engineers are creating something wrongly mixed, to their ears, in the hope that a few thousand people with Polk SDA speakers will be able to fix it with Polk SDA speakers??

Or do you think they assume most have normal 2 speaker stereo, and mix to make it sound just right with that set up?

You just proved my point that you cannot grasp the subject matter.

DarqueKnight

A recording that is mixed to have a realistic sound stage on a pair of conventional speakers will have a better sound stage on a pair of SDAs. A recording that is mixed to have an exaggerated sound stage on a pair of conventional speakers will have a more exaggerated sound stage on a pair of SDAs.

You seem hung up on the technically unsound idea that a recording engineer can compensate for crosstalk in the recording process. That is a technical impossibility.

SDAs do not "fix" anything. All they do is diminish the crosstalk effects created by conventional stereo speakets.

Since you are so sure that a sound engineer can compensate for interaural crosstalk at the recording end. Please explain, and cite credible sources, of how a sound engineer can mix music that will assure crosstalk cancellation at the playback end.

K_M

DarqueKnight wrote: »

@K_M

No, it is not simple at all.

In a previous thread in March of this year, I cited work by Dr. Floyd Toole that explained that interaural crosstalk (comb filtering) cannot be compensated for by recording techniques. Techniques such as using the pan pots to exaggerate the sound stage add an effect that was not in the original performance. No matter what tricks the recording engineer uses to manipulate the sound stage, the loudspeakers at the playback end will still produce interaural crosstalk.

The simple fact that you refuse to accept is that crosstalk cannot be compensated for in the recording process. A pair of conventional stereo loudspeakers will still produce four localization signals rather than the two that were produced by the original sound sources. The only way to compensate for crosstalk signals is to cancel them. There is no way to encode crosstalk cancellation signals in the original recording. This has to be done electronically or acoustically at the playback end.

If you actually read Matt Polk's 1984 paper, he provides an in-depth technical discussion of SDA design and operation principles and provides mathematical justifications.

Correction, it does not NEED compensated for at all.

And yes it absolutely can be done in a recording. But the name will not be "called" SDA. Think about it a bit.

It is not done in recordings because the crosstalk is inherent to the recording from beginning to end playback, and therefore, it is the intended sound meant to be heard.

Sound engineers do not create the sound stage with SDA in mind. Normal 2 speaker stereo is the norm. They mix and master with that in mind, and the placement of sounds are intentionally put where they want them.

Try asking about SDA on pro sound forums.
The guys that mix and master recordings are not so enamored with SDA.

motorhead43026

^^you make the veins pop out on my neck.

Gerres26

motorhead43026 wrote: »

^^you make the veins pop out on my neck.

I agree, I'm no genius but the concept isn't hard to understand. To me it's as simple as this...the SDA technology just further perfects what the sound engineer is trying to do in the studio with the given recording. It does Not add anything to it.

DarqueKnight

K_M wrote: »

Correction, it does not NEED compensated for at all.

An real instrument playing in free space is a single point source. A stereophonic reproduction of that instrument will have to come from two point sources, the left and right speaker. Explain why a single sonic point source represented by two sonic point sources would not NEED compensation for the most accurate sound.

When listening to a real instrument only two signals are received, the acoustic wave from the instrument to the left ear and the acoustic wave from the instrument to the right ear. When listening to a recording of that same instrument played over a pair of stereo loudspeakers, four signals are received, two each from each loudspeaker. The signals at each ear from the opposite speaker must be cancelled for high performance stereo imaging.

K_M wrote: »

And yes it absolutely can be done in a recording. But the name will not be "called" SDA. Think about it a bit.

No, you can't dodge and get off that easy. Provide a technical explanation of how something that is a function of loudspeaker design and performance can be properly dealt with in a recording.

K_M wrote: »

It is not done in recordings because the crosstalk is inherent to the recording from beginning to end playback, and therefore, it is the intended sound meant to be heard.

You are not making sense. Crosstalk is a property of the reproducing loudspeakers, therefore it can't be a part of the original recording. You don't know what you are talking about.

K_M wrote: »

Sound engineers do not create the sound stage with SDA in mind. Normal 2 speaker stereo is the norm. They mix and master with that in mind, and the placement of sounds are intentionally put where they want them.

That's fine. There is no need to create the sound stage with SDA in mind. However, whatever the recording engineer produces will have diminished spatial properties due to interaural crosstalk. There are also other spatial performance criteria that must be considered in addition to interaural crosstalk:

"The stability of the sonic image of headphones is limited by the lack of realistic directional cues. This meant that we would have to do more than eliminate interaural crosstalk. In addition, we would have to find a way for the directional cues contained in the recording, such as they are, to reach the listener's ears in a manner acceptable to the hearing process." [Page 37, col. 1, par. 1, Audio Magazine June 1984]

K_M wrote: »

Try asking about SDA on pro sound forums.
The guys that mix and master recordings are not so enamored with SDA.

I believe that is true, but that is like saying the guys that drive Chevys are not so enamored with BMWs. Most of the guys that mix and master recordings have little to no formal training in acoustics and electronics and they mix music to "sound good" on cheap speakers and portable electronics. Therefore it does not take a stretch of the imagination to understand that people who make a living producing low quality, non-audiophile sound would not be enamored with a "true stereo" loudspeaker system.

Toolfan66

motorhead43026 wrote: »

^^you make the veins pop out on my neck.

Agreed!! Some people should just step away from what they don't understand!! Nor do they want to understand!.,