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  1. #121

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    Quote Originally Posted by eswaroop View Post
    SDA's are an outdated technology. If you want to understand how the SDA system works take a look at this whitepaper.
    http://www.polkaudio.com/downloads/w...WhitePaper.pdf

    The premise is that the recording point is somewhere out in the stage, where both L and R audio signals from the source speakers converge. Today's recordings are tapped at source, meaning the recording audio signals are captured at the same point they make their way to the source speakers (either on stage or in movie recordings). This eliminates any of the intra-aural crosstalk that these speakers are trying to get rid of in the first place. The result is that some of the frequencies that both channels were supposed to output are cancelled out or diminished in this speaker system. This is true typically of low frequency signals, resulting is less bass than what the actual soundstage had.

    Its not a good technology for today. May have worked for live recordings in concerts but not anything else.

    ES.
    You obviously haven't spent any time at all with a properly set-up pair of SDA's. You really have no idea what you're talking about.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass

    Pass Aleph 30; Eastern Electric Mini Max; Adcom GDA600; MIT S3/Z Pc; SDA 1C; Squeezebox; Tubes add soul!

  2. #122

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    I used my SDA's as firewood. Just so I could hear how the flames sounded in true stereo....dingus.

  3. #123

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    Don't quit your day job.
    'Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end."

  4. #124
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    Quote Originally Posted by eswaroop View Post
    SDA's are an outdated technology. If you want to understand how the SDA system works take a look at this whitepaper.
    http://www.polkaudio.com/downloads/w...WhitePaper.pdf

    The premise is that the recording point is somewhere out in the stage, where both L and R audio signals from the source speakers converge. Today's recordings are tapped at source, meaning the recording audio signals are captured at the same point they make their way to the source speakers (either on stage or in movie recordings). This eliminates any of the intra-aural crosstalk that these speakers are trying to get rid of in the first place. The result is that some of the frequencies that both channels were supposed to output are cancelled out or diminished in this speaker system. This is true typically of low frequency signals, resulting is less bass than what the actual soundstage had.

    Its not a good technology for today. May have worked for live recordings in concerts but not anything else.
    ES.
    Where are you getting that info? I have several new recordings done IN THE STUDIO and they sound awesome.

  5. #125

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    Quote Originally Posted by F1nut View Post
    Don't quit your day job.
    Unless you work in...audio, electronics or even physics!

    If so, then you should hang your head low, walk in and resign. Making assumptions about a product you apparently haven't experienced is as relevant as arguing that salt water can't taste any different than fresh water because they are the same compound (H2O).

    I haven't heard SDA's, but after reading about countless people who love them, so many people willing to poor hundreds of dollars into resurrecting these old speakers, and reading about people who have plenty of money to get much more expensive speakers - but choose these, is obviously something any true music lover would have to be at least willing to audition.

    Go troll somewhere else.
    ..... ><////(*>

  6. #126

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    Default Well Well!

    Since so many folks poo-pooed on my original thread I figured I should respond to the same.

    A)Most of the responses are just flat denial without any claim or counter to substantiate my assessment. I'll ignore those.

    B) Dont get me wrong, the SDA SRS speakers are awesome to listen to, no doubt about that. But the question really is if the crosstalk cancellation, which these speakers were touted for, is still relevant. How many of you have tried listening to the same speakers unhooking the cross cable between the speakers on a new recording and comparing with the cable hooked up? This essentially disables the cancellation circuits, and assuming the rest of the acoustics are tweaked try it again.

    Back to someone's comment that the speakers are designed to cancel the crosstalk at listening point, this would mean that standing out in the crowd and listening through the speakers in a live concert today is not the real sound.

    ES



    Quote Originally Posted by eswaroop View Post
    SDA's are an outdated technology. If you want to understand how the SDA system works take a look at this whitepaper.
    http://www.polkaudio.com/downloads/w...WhitePaper.pdf

    The premise is that the recording point is somewhere out in the stage, where both L and R audio signals from the source speakers converge. Today's recordings are tapped at source, meaning the recording audio signals are captured at the same point they make their way to the source speakers (either on stage or in movie recordings). This eliminates any of the intra-aural crosstalk that these speakers are trying to get rid of in the first place. The result is that some of the frequencies that both channels were supposed to output are cancelled out or diminished in this speaker system. This is true typically of low frequency signals, resulting is less bass than what the actual soundstage had.

    Its not a good technology for today. May have worked for live recordings in concerts but not anything else.

    ES.

  7. #127

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    Quote Originally Posted by eswaroop View Post
    Back to someone's comment that the speakers are designed to cancel the crosstalk at listening point, this would mean that standing out in the crowd and listening through the speakers in a live concert today is not the real sound.
    The fact that you made that comment clearly demonstrates that you don't understand the difference between listening to music live (in concert or in the studio) and listening to recorded music. Therefore, your opinions on the matter are without merit.
    'Political Correctness'.........defined

    "A doctrine fostered by a delusional, illogical minority and rabidly promoted by an unscrupulous mainstream media, which holds forth the proposition that it is entirely possible to pick up a turd by the clean end."

  8. #128

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    @eswaroop

    The SDA effect is not dead. Polk has been making speakers with the technology for the much (a slim majority, actually) of the past 25 years. While the perhaps most loved SDA's were from '88-'91 (1C/2B/CRS+/SRS's), the technology made another appearance with the SRT's around '95 and again with the SurroundBars around '05 (I think) and have been made since. SDA isn't dead and I don't think it will be any time soon.
    Last edited by Bobsama; 09-25-2010 at 12:24 PM.
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  9. #129
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    Quote Originally Posted by eswaroop View Post
    Since so many folks poo-pooed on my original thread I figured I should respond to the same.

    A)Most of the responses are just flat denial without any claim or counter to substantiate my assessment. I'll ignore those.

    B) Dont get me wrong, the SDA SRS speakers are awesome to listen to, no doubt about that. But the question really is if the crosstalk cancellation, which these speakers were touted for, is still relevant. How many of you have tried listening to the same speakers unhooking the cross cable between the speakers on a new recording and comparing with the cable hooked up? This essentially disables the cancellation circuits, and assuming the rest of the acoustics are tweaked try it again.
    ES; before I needed to use the AI-1 cable due to my Trivista's mono block design, I had two Adcom 565s strapped together powering the lows and a Parasound HCA 1000A powering the high. I tried disconnecting the SDA cable on many LPs, including Maroon 5, The Shins, Arcade Fire, The Decemberist as well as classical, jazz, rock, etc. The sound-stage collapsed and the imaging was smeared. If I wanted any semblance of a sound-stage or good imaging, I had to keep trying to toe in the speakers. Forget that as I only, one time, got a decent sweet spot and it was very narrow and short.

    Sorry but I think your wrong. I've heard many many high end speakers over the past few years, as a matter of fact I'm heading to an Audio Show at Quest for Sound tomorrow and no speaker under $17k came close to the sound-stage, imaging etc that my 1.2TLs have.:)

  10. #130

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    Crosstalk cancellation has very little to do with "a recording process" it's a fundamental aural phenomenon that occurs specifically with a stereo signal and a pair of front speakers. Can this phenomenon be lessened or increased based on the way a piece of music is recorded? Sure, but it can never be eliminated completely. Passive SDA's and the more current digital algorithms built into products like the Surround Bars work extremely well and there really hasn't been anything else on the market to combat this natural aural phenomenon.

    If you really want to read something about the original passive SDA and the theory, ditch the current white paper and read the original SDA white paper published in 1985. The current white paper is more about the current electronic implementation by way of DSP algorithms than the original passive SDA theory. The fundamental idea is still true, but it's a slightly different animal.

    You are so far off base as far as your interpretation of how this phenomenon occurs and how it's combated by SDA's. If you're just trying to controversial and spark discussion, it's a poor way of doing it. You come off as a fool.
    Last edited by heiney9; 09-25-2010 at 12:33 PM.
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass

    Pass Aleph 30; Eastern Electric Mini Max; Adcom GDA600; MIT S3/Z Pc; SDA 1C; Squeezebox; Tubes add soul!

  11. #131

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    Quote Originally Posted by eswaroop View Post
    Since so many folks poo-pooed on my original thread I figured I should respond to the same.

    A)Most of the responses are just flat denial without any claim or counter to substantiate my assessment. I'll ignore those.


    ES
    Quote Originally Posted by Kenneth Swauger View Post
    Hello ES,
    You're probably going to get as much flack from your posting as an unescorted B17 flying over Berlin in the daylight in 1942.
    The crosstalk the SDA speakers were designed to reduce is not so much the result of the recording technique used, but rather what happens when two speakers are placed in a room. Sound from the left channel reaches the left ear, but some of it is heard by the right ear. The same thing happens with the sound produced by the right audio channel. The result is a diluting of the stereo image potential. Next time you're listening to a sound system try this experiment. Place one of your hands vertically between your eyes, resting the edge of your hand close to your head. Then take the other hand and place it in front of the first one, creating a barrier between the left half and right half of your face. See how this changes the stereo image you hear, strengthening the sound-stage.
    I'm sure many other SDA owners will chime in and give you their experience.
    You might want to put on that flack jacket, now.
    Cheers, Ken

    nuff said
    The Gear... Carver "Statement" Monoblocks, Polk Audio "Signature" Reference Series 1.2TL with complete mods, Polk audio AB700/800 "in-wall" surrounds, Dodd Audio MLP, Pioneer Elite SC-65, Peachtree I-DAC, Oppo BDP-93, Yamaha PX-3 Turntable, with Sumiko BPS EVOIII, Pioneer PDD 9MkII SACD Player, SimAudio moon 110lp phono preamplifier

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  12. #132

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    eswaroop- SDA's might not be for you so perhaps if you do own a pair it's time to sell them. If you don't own a pair I have no idea why you'd want to stir the pot. There are hundreds and hundreds of speaker designs out there. Find whatever floats you boat.

    Not trying to tell you that you have to like SDA's, but your comments are basically false because you don't understand a) inneraural crosstalk b) how SDA's are engineered. That's why you're catching so much flak, not nec because you don't like SDA's.

    H9
    Last edited by heiney9; 09-25-2010 at 12:58 PM.
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass

    Pass Aleph 30; Eastern Electric Mini Max; Adcom GDA600; MIT S3/Z Pc; SDA 1C; Squeezebox; Tubes add soul!

  13. #133

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    Quote Originally Posted by eswaroop View Post
    Back to someone's comment that the speakers are designed to cancel the crosstalk at listening point, this would mean that standing out in the crowd and listening through the speakers in a live concert today is not the real sound.
    Standing out in a crowd and listening through the speakers at a live concert IS NOT the real sound. Most concerts of this nature are flat, two-dimensional, noisy, distorted, acoustically compromised representations of the REAL sound. The REAL SOUND would be listening to the un-amplified performers in an acoustically correct room when seated in a position front and center of the stage.

    Quote Originally Posted by eswaroop View Post
    Most of the responses are just flat denial without any claim or counter to substantiate my assessment. I'll ignore those.
    I have been an SDA owner since 1987. There are many others on this forum (and in this thread) who have similar personal experience. Feel free to ignore us. That is your right, but you don't lend much credibility to your argument when you ignore relevant personal experience.

    Quote Originally Posted by eswaroop View Post
    How many of you have tried listening to the same speakers unhooking the cross cable between the speakers on a new recording and comparing with the cable hooked up? This essentially disables the cancellation circuits, and assuming the rest of the acoustics are tweaked try it again.
    Probably 100% or close to 100% of SDA owners have tried this. It has been discussed many times on this forum and elsewhere.

    Quote Originally Posted by eswaroop View Post
    Dont get me wrong, the SDA SRS speakers are awesome to listen to, no doubt about that. But the question really is if the crosstalk cancellation, which these speakers were touted for, is still relevant.
    Some excellent advice was given here:

    Quote Originally Posted by heiney9 View Post
    Crosstalk cancellation has very little to do with "a recording process" it's a fundamental aural phenomenon that occurs specifically with a stereo signal and a pair of front speakers.
    As long as stereophonic systems are predominantly two channel systems, the cancellation of interaural crosstalk will be relevant. Anyone really interested in understanding how SDA's work should get Matthew Polk's article from the June 1984 issue of Audio magazine, "Polk's SDA Speakers - Designed-In Stereo".

    What must be understand is that the concept of interaural crosstalk is about addressing the limitations of using two sound sources (loudspeakers) to recreate an event that was composed of multiple point sources distributed throughout a three dimensional space. Therefore, no matter what type of stereophonic recording technique was used (two microphones, a microphone at each performer's location, etc.) to record a performance, that performance still has to be reproduced by only two sound sources (loudspeakers) and that reproduction will be diminished in spatial realism by the effect of interaural crosstalk.

    Before one can gain a good understanding of how SDA's work, one needs to gain a good understanding of how stereophonic systems work. Matthew Polk's 1984 paper is a good place to start. Many good references on stereophonic reproduction can be also found in this thread:

    Link: "A Survey Of Early Stereophonic System Subjective Evaluation"
    "Polk SDA-SRSs are hopelessly out of date both sonically and technologically... I see no value whatsoever in older SDA speakers."~Audio Asylum Member
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  14. #134

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    Dear ESWAROOP,
    As VP of Engineering at Polk I suppose your question about SDA is aimed pretty squarely at me. I've been designing speakers at Polk for 33+ years now and I have been part of the SDA design work through all of its evolution which continues on even now.
    So, let me answer your question about the continuing relevance of SDA and Interaural crosstalk cancellation. Yes, SDA is still relevant. I'm tempted to leave it at that since several other folks have stated the reasons quite accurately in this thread but you seemed unconvinced. The supporting reasons for SDA’s continued relevance are quite simple actually and perhaps it is the lack of complexity makes it all seem too easy. Matthew’s article on SDA, published in the Audio magazine June 1984 issue, "Polk's SDA Speakers - Designed-In Stereo" explains SDA in great detail and it is also referenced by other respondents to the question. I cannot provide that level of detail here so I advise a good of that article. http://www.polkaudio.com/downloads/w...WhitePaper.pdf
    I can however provide a brief summary to address your questions.
    It is a fact that when speakers L & R are played in a typical arrangement for stereo the sound from the left speaker reaches the right ear (about 0.5ms later than the left due to the distance between our ears) and vice-versa for the right speaker. Interaural crosstalk was understood to exist at stereo’s inception but given the great step forward offered by stereo encoding on vinyl as compared to mono and the lack of understanding as to just how much better it might be if Interaural crosstalk were cancelled, it was left unaddressed for about 30 years. Polk developed SDA to cancel this crosstalk acoustically by the specific arrangement of the drivers on the baffle and the signals they are fed. By adding a driver (or array) to each speaker (L&R), separating the drivers 5-7 inches laterally and feeding this “Dimensional driver” only the anti-phase least-correlated information between the L & R channels. A cancelation signal is therefore sent to each ear and, due to the offset position, arrives at precisely the same time as the crosstalk from the opposite channel and the crosstalk is cancelled. An in-depth analysis of the Hass or precedence effect that describes our ear<>brain computation for determining how we perceive the direction of a sound source was necessary in order to properly tailor the bandwidth and gain for these “Dimensional” signals. Matthew found, during this investigation, that Interaural crosstalk not only interfered with our ability to perceive the recorded soundstage, it also provided aural queues as to the location of the loudspeakers.
    So, SDA has to do with the sound being played back from a set (or sets) of loudspeakers. The manner in which a recording is made does not affect SDA. SDA does not create or add any spatial “effect” to the recording. It simply removes a distortion in the payback chain. The effect of a well tuned system with SDA is to dramatically improve our perception of whatever soundstage the recording engineer has created in the studio. Sonic images become more stable and coherent. They remain stable as program levels and tonality change throughout a performance. The loudspeaker disappear as a sound source and instead of a soundstage that exists only between the loudspeakers, the soundstage fills the entire listening space. It is, to a much greater degree than with non-SDA, more like the performance is taking place in front of the listener which is the point of hi-fi after all.
    Interaural crosstalk cancellation can be achieved electronically by deriving a cancelation signal and mixing it back into the original with the appropriate delays, but the electrically you can only fix the delay so as to account for a single listening position. Our acoustic approach as is more tolerant of listener position and head angle. As the listener moves closer or farther away the angle between the listener and the offset “Dimensional” drivers narrows or widens and thus the delay is adjusted accordingly.
    In home theater setups there is the consideration for multiple pairs of speakers around the room. SDA will work for a pair of speakers in front or behind a listener. It is essentially benign for a pair of speakers located to the side. So, as a basic technology it is still a potential benefit in HT setups . We have sold SRT systems consisting of front and rear SDA stacks with the SRT center (the center is not SDA for obvious reasons) and this created an amazing degree of image accuracy. If you can find SRS or SRTs and have the room to set up 4 as front as rear I suggest that you do it. Use a center channel in the front and back and use the 6.1 mode for multichannel HT or music. It will sound amazing.
    So, SDA is still relevant. The simple reasons that it fell out of favor for freestanding L & R traditional speakers is that a) it requires extra drivers and a larger front baffle and adds significant cost due to the extra drivers and crossover parts, and b) the retailer base needed to capably demo the product is near extinction despite my hope for resurgence. We continue to look for ways to employ SDA in a more compact and cost efficient format. We use SDA on the front channels in several of our current Surround Bars, both passive and powered, with great success.

    I hope this addresses your questions. Keep listening.

    Stu
    Stu

  15. #135

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    Stu, great to see you posting not so much to settle some small squabble but for your indepth techical knowledge. I hope you continue to post this knowledge when necessary. I love the "geeky" technical explanations and analysis.

    H9
    "Appreciation of audio is a completely subjective human experience. Measurements can provide a measure of insight, but are no substitute for human judgment. Why are we looking to reduce a subjective experience to objective criteria anyway? The subtleties of music and audio reproduction are for those who appreciate it. Differentiation by numbers is for those who do not".--Nelson Pass

    Pass Aleph 30; Eastern Electric Mini Max; Adcom GDA600; MIT S3/Z Pc; SDA 1C; Squeezebox; Tubes add soul!

  16. #136

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    +1 thanking Stu for his insight, that is my kind of administration, yet another reason to love this company.

    As an owner of SDA's who enjoys modern music, I can assure you that I have fiddled with removing the crossover cable and listening on dozens of different modern artists, from rock to hiphop, and electronic to drum and bass. The vast majority of the music that I listen to clearly benefits from the SDA interconnect, and everyone who listens to my system remarks on the clarity.

    Unless you are a dedicated quality headphone listener, my assessment is "It is like listening to it for the first time".

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    WOW! Thanks Stu!
    Main System: Polk SDA SRS 1.2 Speakers, Sunfire Signature 600~two Amp, Carver C-16 Preamp, Carver TX-11b Tuner, Marantz 6350Q TT, Philips CDR-775 Recorder, Teac V-707RX Cassette Deck, Signal Cable Double Run Speaker Cable

    Upstairs Den: Marantz 2325 Receiver, Marantz 5220 Cassette Deck, Marantz HD-880 Speakers, Marantz 6370Q TT

    Exercise (Kabuki speaker) Room: Kenwood KR-9600 Receiver, Pioneer CS-99a Speakers, Sansui SP-X9000 Speakers (not pretty, but LOUD! :) )

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    hell of a first post Stu...... nice reading ...thank you sir
    Last edited by fossy; 10-05-2010 at 07:26 PM. Reason: added the sir......

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    Default Thanks for the explanation

    Hi Stu,

    Thanks for the detailed explanation. I had a chance to audition a pair of SDA - SRS speakers recently, they sounded great but seemed to be suppressing some frequencies to an extent. I was hasty to conclude this as an outcome of the crosstalk cancellation. Probably had more to do with the room acoustics than anything else. I guess I passed an opportunity to buy a pristine set of these speakers in haste :).

    Btw, I have Polk RTI 12's at home and love them. They are not comparable to the SDA's but are great on their own.

    Thanks,

    ES

    Quote Originally Posted by Stu Lumsden View Post
    Dear ESWAROOP,
    As VP of Engineering at Polk I suppose your question about SDA is aimed pretty squarely at me. I've been designing speakers at Polk for 33+ years now and I have been part of the SDA design work through all of its evolution which continues on even now.
    So, let me answer your question about the continuing relevance of SDA and Interaural crosstalk cancellation. Yes, SDA is still relevant. I'm tempted to leave it at that since several other folks have stated the reasons quite accurately in this thread but you seemed unconvinced. The supporting reasons for SDA’s continued relevance are quite simple actually and perhaps it is the lack of complexity makes it all seem too easy. Matthew’s article on SDA, published in the Audio magazine June 1984 issue, "Polk's SDA Speakers - Designed-In Stereo" explains SDA in great detail and it is also referenced by other respondents to the question. I cannot provide that level of detail here so I advise a good of that article. http://www.polkaudio.com/downloads/w...WhitePaper.pdf
    I can however provide a brief summary to address your questions.
    It is a fact that when speakers L & R are played in a typical arrangement for stereo the sound from the left speaker reaches the right ear (about 0.5ms later than the left due to the distance between our ears) and vice-versa for the right speaker. Interaural crosstalk was understood to exist at stereo’s inception but given the great step forward offered by stereo encoding on vinyl as compared to mono and the lack of understanding as to just how much better it might be if Interaural crosstalk were cancelled, it was left unaddressed for about 30 years. Polk developed SDA to cancel this crosstalk acoustically by the specific arrangement of the drivers on the baffle and the signals they are fed. By adding a driver (or array) to each speaker (L&R), separating the drivers 5-7 inches laterally and feeding this “Dimensional driver” only the anti-phase least-correlated information between the L & R channels. A cancelation signal is therefore sent to each ear and, due to the offset position, arrives at precisely the same time as the crosstalk from the opposite channel and the crosstalk is cancelled. An in-depth analysis of the Hass or precedence effect that describes our ear<>brain computation for determining how we perceive the direction of a sound source was necessary in order to properly tailor the bandwidth and gain for these “Dimensional” signals. Matthew found, during this investigation, that Interaural crosstalk not only interfered with our ability to perceive the recorded soundstage, it also provided aural queues as to the location of the loudspeakers.
    So, SDA has to do with the sound being played back from a set (or sets) of loudspeakers. The manner in which a recording is made does not affect SDA. SDA does not create or add any spatial “effect” to the recording. It simply removes a distortion in the payback chain. The effect of a well tuned system with SDA is to dramatically improve our perception of whatever soundstage the recording engineer has created in the studio. Sonic images become more stable and coherent. They remain stable as program levels and tonality change throughout a performance. The loudspeaker disappear as a sound source and instead of a soundstage that exists only between the loudspeakers, the soundstage fills the entire listening space. It is, to a much greater degree than with non-SDA, more like the performance is taking place in front of the listener which is the point of hi-fi after all.
    Interaural crosstalk cancellation can be achieved electronically by deriving a cancelation signal and mixing it back into the original with the appropriate delays, but the electrically you can only fix the delay so as to account for a single listening position. Our acoustic approach as is more tolerant of listener position and head angle. As the listener moves closer or farther away the angle between the listener and the offset “Dimensional” drivers narrows or widens and thus the delay is adjusted accordingly.
    In home theater setups there is the consideration for multiple pairs of speakers around the room. SDA will work for a pair of speakers in front or behind a listener. It is essentially benign for a pair of speakers located to the side. So, as a basic technology it is still a potential benefit in HT setups . We have sold SRT systems consisting of front and rear SDA stacks with the SRT center (the center is not SDA for obvious reasons) and this created an amazing degree of image accuracy. If you can find SRS or SRTs and have the room to set up 4 as front as rear I suggest that you do it. Use a center channel in the front and back and use the 6.1 mode for multichannel HT or music. It will sound amazing.
    So, SDA is still relevant. The simple reasons that it fell out of favor for freestanding L & R traditional speakers is that a) it requires extra drivers and a larger front baffle and adds significant cost due to the extra drivers and crossover parts, and b) the retailer base needed to capably demo the product is near extinction despite my hope for resurgence. We continue to look for ways to employ SDA in a more compact and cost efficient format. We use SDA on the front channels in several of our current Surround Bars, both passive and powered, with great success.

    I hope this addresses your questions. Keep listening.

    Stu

  20. #140

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    Quote Originally Posted by heiney9 View Post
    Stu, great to see you posting not so much to settle some small squabble but for your indepth techical knowledge. I hope you continue to post this knowledge when necessary. I love the "geeky" technical explanations and analysis.

    H9
    Yeah, not a bad post for a newbie :p

    Joke aside, his post is as enjoyable as reading the actual SDA white paper and also complements it. I would hope Stu would post more often as his knowledge is a real joy to read.

    While time changes and companies must adapt with the new trends and market, there are some technologies that aren't made to be changed or to disappear but should rather be combined with newer technologies which are more effective in today's world. Afterall, isn't SDA a huge part of Polk success and respect from this industry?

    I do feel that SDA is part of such technology (that shouldn't change or disappear) and while it is a great thing that it is combined with the solution Polk offers over HTIB (Surround Bars that is) I think it also should be combined with the newer floor standing offers. I understand the extra costs but we also have to realize costs are much lower than they use to be in the past when considering Chinese manufacturing of drivers and enclosures for Polk drives the company costs and overhead down. It is an humble Technical understanding I have but aside from the extra drivers and additon to the Xo, this technology is basically adding inversion to create the SDA effect. Therefore wouldn't there be any ways for Polk to review the engeneering to drop their cost while keeping an effective technology alive in most of their products as I feel it is a big part of Polk success through time??? I would believe Stu's highly descriptive post on the benifit of SDA technolgy should warrant that Polk should still spend time and effort on this great technology.

    I agree with Stu that the days of retailers having the proper facilities to demo such quality product are long gone but I think the approach that Polk was seeking through one of his post seeking for in-home demos might be the alternate solutions. Retailers are not after quality products but rather about huge profit margins made quickly so if Polk is serious about still providing quality product for a niche clientele, new avenues out of the typical brick and mortar stores is to be looked at. In-home demo and marketting while online sales could well be the solution (also consider the offering could be a lot more friendly with eleminating the middle man (B&M) hefty profit margins).

    I honestly feel that if some of the sort is not implemented, I feel that Polk will have to fall in the trap of mosts manufacturers which now offer mediocer products in order to accomodate the retailers / B&M demands versus its actual clientele. The biggest reason I'm loyal to Polk and its product is its own loyalty and closeness to its clientele so I sure hope Polk will never let the pressure and will of its retailer destroy that. I always requested the best quality possible for any of my $$$ spent and Polk has yet always achieved that and of course, I don't expect any less in the future.

    Cheers!
    TK

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    Dear ESWAROOP,
    I trust your ears on this one. The SRS could have ben damaged over time or the setup less that adequate or the tuning might not be as much to your liking.

    aS to the RTI 12, well that IS vintage Polk. Great choice. I had a pair at my home for a few years.

    Keel Listening,
    Stu
    Stu

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    Stu,

    I had the SRT system with the towers in front of me and behind me. It was my first home theater system and when I sold them due to financial reasons I never thought twice about it. Now (13 years later) I have a dedicated room in the basement and have been demoing speaker systems left and right only to be feeling that something is missing. The pin point imaging and realism that the SRT system gave me I took for granted being as I never had anything before it to compare it to. The only system I compared it to was the M&K 5000 system that happened to be being sold where I bought my Polks. To me it was a no brainer as the Polks didn't seem to have any gap in the sound stage from left to right even in between the speakers, it just seemed like a solid wall of sound. With the M&K's they were clear and played loud but I was never emotionally engaged by them. I knew about the SDA technology but really never understood what it did. I just assumed when I decided to get another theater system that after 13 years speakers would have come so far in advancements that it would be easy to find the equal of what I had. Now that I know that there is a scientific reason from the technology in the SRT system I had that it satisfied me in the ways that it did I am really depressed as I know why it is I'm not happy demoing systems many times more expensive then the SRT's. I hope that someday you guys can figure a way to develop something with the SDA technology that is on par or exceeds the SRT's I had. Even if it's only a statement piece and sold directly through Polk and not through retailers as I know from experience that the people I bought my system from knew nothing on how to set it up properly and I had to have Paul and Kenneth come out to my house and help me dial it in as I live in PA. That would probably keep the cost down as well if only sold direct. I remember when Cinepro started selling the SRT system with their amps substituted for the sub amps. Then when Eric (owner of Cinepro) died and the original company broke up the SRT speakers again went away for good. I guess to make a long story short I just have two questions. 1:) If Cinepro wouldn't have went under would Polk have continued to make the SRT speakers just for them or were they just clearing out the inventory, and 2:) should I just try to forget what I had and settle for a conventional system that does everything but SDA or does Polk have any real intentions of bringing out something in the future that could equal or better the SRT system?

    Regards, Derek

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    I've been designing speakers since I was a teenager.. nearly every configuration possible. I owned a car audio shop where i was able to test theory , true to life performance and variable designs.I can humbly admit I was successful in many areas, and along with that equally built many failed attempts.lol..For a Legendary design such as the SDA line Mr.Polk reached beyond the imagination and was able to find success...What I wouldn't do to get a spot in the R and D of such a product...hindsight right?20/20?.lol
    Read thspecs,

    read the reviews, do the research but most importantly...Listen and make your own decisions.
    Polk SDA 1Cs.
    Polk CDAS
    Yamaha RX-V661
    Yamaha M65
    Yamaha CDX-910
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    AR HT 60 pwrd.sub

  24. #144
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    " Read the specs, read the reviews, do the research but most importantly...Listen and make your own decisions. "

    Nice signature, I wished I had thought of it.

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    you really don't want to get me going on this again... :)
    mike

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    Quote Originally Posted by mjmcg View Post
    you really don't want to get me going on this again... :)

    ok, Go ahead.
    Polk Audio SDA SRS 1.2TL's
    With new Exotic wood, Sonicaps, Mills & RDO198's - Born on 4-24-1989 and Signed by Matthew Polk!!!!


    My Polk SDA SRS 1.2TL's http://www.LASAREATH.com/


    It All Started here: http://tinyurl.com/lasareath2

    Part Deux: http://tinyurl.com/lasareath3

    Car Stereo---->http://www.salsleaf.com/leaf_stereo/index.htm<---- NEW for 2013

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    I love this thread. It's like a gift that keeps on giving. Proud SDA owner for 22 years and counting.

    Started with CRS+'s, then 2B's that I did the typical mods to, then to 1C's that I also did the basic tweeter/xo/inductor mods.

    The Mrs. and I will likely be downsizing the homefront significantly once the boy is out of high school in a few years, so I don't think my dream of 1.2TL's in a huge room is going to come about. That's why I just bought Sal's CRS+'s, what's old is new again.

    Planning on building the uber pair of 4.1TL's for the downsized home of the future - Larry's rings, gimpods xo boards, Sonicaps, Mills, rdo-198's, cardas posts, north creek inductors, wood veneer, new grill cloth, dynamat, mortite, and maybe even the kitchen sink!
    Good music, a good source, and good power can make SDA's sing. Tubes make them dance.

  28. #148

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    Ah, how can I forget? Custom SDA cable to eventually morph into an AI-1/Dreadnought
    Good music, a good source, and good power can make SDA's sing. Tubes make them dance.

  29. #149

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    Reported^^^^
    Quote Originally Posted by Timothy Smith View Post
    WOW!

    That's like working your way through Katie Perry in order to get to Rosie O'Donnell.

  30. #150

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    Reported post #149 & 150

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