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Polk's New Flagship, Legend Series Speaker: Reintroduces upgraded SDA Technology

HammerSandwich

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any thoughts as to WHY some songs sound better than others? is it an amplification issue perhaps?
Different recording techniques. (The source material is usually 99% of the equation.) If it were about amplification, it would affect all recordings, not some songs.
 

Head_Unit

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The part that was bothersome to me was use of the word "problem." Interaural crosstalk is not a "problem" it's inherent in how the recordings are mixed! So SDA like the Carver Sonic Hologram is an EFFECT that is INACCURATE though like many effects yes it can be enjoyable.
To "fix" this "problem" it would be cheaper to hold a piece of acoustic foam up to your nose and perpendicular to your face and the floor...
(there was someplace that had a drawing of that, I swear it was in an Audio Engineering Society preprint or someplace serious like that, hilariously tongue-in-cheek).
P.S. I did like the original SDAs, though more because I felt they had a clearer sound than a lot of speakers at the time.
 

Terry Stahly

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I spoke with a Revel dealer and he told me since I was using a pair Martin Logan Balanced Force 212's that if I wanted to replace my Bowers 801's the revel f226be would be better since the base is augmented by some quality subs. I can agree with that but my question is for two channel like listening to the Allman Brothers or some good rock or male and female vocalists and classical if I would miss the low end of will the ML 212's pick up where the revel f226be leave off. I am not that knowledgable on how subs work with stereo sound or if they even do? I use a Marantz 8805 as a processor preempted out to a Krell 700cx amp for left and right.
 

Thomas savage

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I spoke with a Revel dealer and he told me since I was using a pair Martin Logan Balanced Force 212's that if I wanted to replace my Bowers 801's the revel f226be would be better since the base is augmented by some quality subs. I can agree with that but my question is for two channel like listening to the Allman Brothers or some good rock or male and female vocalists and classical if I would miss the low end of will the ML 212's pick up where the revel f226be leave off. I am not that knowledgable on how subs work with stereo sound or if they even do? I use a Marantz 8805 as a processor preempted out to a Krell 700cx amp for left and right.
What's this goto do with the OP?
 

anmpr1

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...but my question is for two channel like listening to the Allman Brothers or some good rock or male and female vocalists and classical if I would miss the low end of will the ML 212's pick up where the revel f226be leave off.
Maybe for classical or female vocals, but for that authentic Allman sound you should probably go with something a little different. ;)

allman.jpg
 

Terry Stahly

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Any ideas? I was thinking since 90% of my listening is home theater they would be fine and also considering the larger F228be but certainly curious as to a couple more you might suggest.
 

Invalidtoday

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Just read this whole thread, can't figure out why some of you guys think it's an inaccurate effect when stereo itself is an inaccurate effect but sounds good.
 

CDMC

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Just read this whole thread, can't figure out why some of you guys think it's an inaccurate effect when stereo itself is an inaccurate effect but sounds good.

Because it is an internet forum and that is what people do. But good job on the old thread resurrection. :)
 

DonH56

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Just read this whole thread, can't figure out why some of you guys think it's an inaccurate effect when stereo itself is an inaccurate effect but sounds good.

Stereo is mixed for stereo speakers. I heard the original SDA line and it was one of those things that sounded impressive but quickly sounded "fake" because it trashed the stereo image in favor of something different and unexpected by the mastering engineers. I had the same feeling about Bose 901's; impressive at first, but having everything spread across the entire front wall was just too much. If you like the effect that's cool; it is subjective like so many things audio. Personally if I had them I'd like an easy way to switch it off since I listen to a lot of solo and small-group music for which the SDA effect just didn't sound right to me.
 

anmpr1

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Just read this whole thread, can't figure out why some of you guys think it's an inaccurate effect when stereo itself is an inaccurate effect but sounds good.
A lot depends on just how much 'inaccuracy' one can tolerate, and what's important to the listener. As you correctly point out, stereo itself is an 'inaccurate effect' inasmuch as it's an attempt to recreate a full dimensional soundfield from two adjacently spaced sources. Generally it leaves a center hole that is often not 'covered' very well-- depending a lot on recording technique, but also the radiation pattern of the loudspeakers in combination with the listening room.

In the early days of stereo reproduction this sonic artifact was readily apparent to pretty much anyone, as everyone was coming from monophonic which was a 'point source'. With widely spaced speakers this 'defect' was more prevalent, and sometimes made over by the use of a center speaker and a 'blend' channel. Paul Klipsch's 'solution' was one of the most widely known work around. I think David Hafler had one, and his preamps always featured a 'blend' control to minimize this peculiar stereo artifact.

As far as stereo goes, in the 1980s there were a lot of serious people seriously predicting the death of two channel reproduction due to the introduction of sophisticated surround systems which were said to help to eliminate inherent limitations of two speaker hi-fi. As we know, that prediction has not happened.

Stereo is mixed for stereo speakers. I heard the original SDA line and it was one of those things that sounded impressive but quickly sounded "fake" because it trashed the stereo image in favor of something different and unexpected by the mastering engineers. I had the same feeling about Bose 901's; impressive at first, but having everything spread across the entire front wall was just too much. If you like the effect that's cool; it is subjective like so many things audio. Personally if I had them I'd like an easy way to switch it off since I listen to a lot of solo and small-group music for which the SDA effect just didn't sound right to me.

The 'problem' with the Polk 'solution' as @DonH56 points out it that the effect is both widely room dependent and recording dependent. I've not heard it, but the reviews I've read indicate that it's effect is quite variable, sometimes good, sometimes not so good--so it's not a 'one size fits all' solution.

In an earlier comment @Kal Rubinson points out that the design requires a lot of amplifier power inasmuch as half the drivers are cancelling a part of the other driver's signal. So all things being equal it's a more expensive solution than, say, the Carver 'sonic hologram' electronic box, the latter having the benefit of being able to be switched off if you don't like it, or don't want to use it on a particular recording.

All that said, and as I always say, loudspeakers are the really only major subjective piece of gear left in the the hi-fi chain, so if Polk floats your boat, and if you have the dollars and space for SDA, then that'd be the way to go. Either that or buy a used Carver box and see how that goes for you.
 

Head_Unit

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Just read this whole thread, can't figure out why some of you guys think it's an inaccurate effect when stereo itself is an inaccurate effect but sounds good.
Like the Carver Sonic Hologram and BBE and planar speakers and a host of other technologies, SDA cannot reproduce a mix as intended (which is what I think of as "accurate." Crosstalk IS part of the stereo mix, that's how the mix engineers listened to it. Now if you like the effect those technologies produce, hey, enjoy!

For instance, when I worked in the bowels of gigantoid audio corporation #17, we had a bunch of discussions about BBE. I said it was total bullsh!t how they said they would fix the delayed harmonics or whatever, since they could not know exactly what was there in the first place.* Did it spruce up many recordings in a noisy car? Yeah! Did I press the botton? Yeah! But while it was more fun you couldn't say it was more accurate.

And planar speakers (I had a set of Martin Logans for years in a listening room): That sound is never how the mix was made, so they are not accurate, yet they can certainly make a nicer/fascinating sound in some ways.

*also my objection to MQA's I think they called it "deblurring" which would purportedly fix was it time problems in the recording chain? But if you don't know the chain, how can you do that? I never saw that technology explained.
 

anmpr1

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...reproduce a mix as intended (which is what I think of as "accurate." ...and planar speakers: That sound is never how the mix was made

Not sure what you mean with the words 'as intended', but it appears you mean it is whatever the producer heard at mixdown (or possibly the 'sonic canvas' he was attempting to create)?

If that's the idea of 'accurate', then good luck with that. If that's numero uno on the criteria list, then the only 'accurate' loudspeaker for any given recording would be whatever the producer used (and however he used it), which was probably a medium sized pro monitor sitting at ear level, on the console a few feet away from the board.

In any case, many 'pop' recordings are totally synthetic, having no natural analog in the real world. Back in the day much pop was mixed down to sound 'good' on a single AM car radio--do you want a Delco 6x8 in your living room?

Some recordings are 'meant' to 'capture' an event's 'live' sound. You want 'Europe '72' as it was intended? Start stacking JBL and EV speakers up to the ceiling.

Moving away from the studio, what about the old Harry Pearson idea of the 'absolute sound'--acoustic instruments in a natural space? Do you think he achieved that with his Infinity IRS in his small listening room? I'd bet that Qauds would have painted a clearer picture for him, albeit on a much smaller level.

Also, it is not uncommon for 'classical' producers add artificial electronic enhancements to the mix (along with multimiking and weird mixing schemes). And I can absolutely state with certainty that no loudspeaker is going to reproduce a realistic image of the live sound of an orchestra in your living room, regardless of how (and with what gear) the mix was made.

The point is, at the loudspeaker-living room interface not everyone wants or expects (or thinks it is even possible for) the studio to be the sonic arbiter of good sound. On a personal note I understand that some classical studios use B&W loudspeakers for their monitors. I have never been a fan of the Bowers and Wilkins sound, but I like some of the recordings created on them. It's a personal thing. That's why so many different loudspeaker types exist.
 

mhardy6647

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I don't think that even most of the SDA faithful would say the loudspeakers were more faithful to the vision of the content creators, much less more accurate. I do think that they'd say that the SDA... umm... soundfield (I do know they don't like it to be referred to as an "effect") has unique spatial properties that they appreciate.

EDIT: Oh, and I'll readily cop to being a Polk fanboy from way back (1976) -- but I'm not much of an SDA fan (nor apologist).
 
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anmpr1

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I don't think that even most of the SDA faithful would say the loudspeakers were more faithful to the vision of the content creators, much less more accurate. I do think that they'd say that the SDA... umm... soundfield (I do know they don't like it to be referred to as an "effect") has unique spatial properties that they appreciate. EDIT: Oh, and I'll readily cop to being a Polk fanboy from way back (1976) -- but I'm not much of an SDA fan (nor apologist).

I recall when a lot of West Coast music was produced using JBL monitors. That sound is what the producer 'heard' at work. But I'd read articles from producers who said they'd never want those monitors in their living room as a home speaker. On the other hand, the JBL story is that studio folks were taking 4311 monitors home, and that was the inspiration for the L100--a 4311 in nicer clothes.

I recall a demo of the L100 and Polk RTA-12 (not SDA) in or around 1978 or '79. I thought the Polk was a decidedly superior loudspeaker overall, and even better than the Dahlquist DQ-10 that the dealer wanted to sell me. I bought a set of Polks, but later sold them, replacing them with electrostatic speakers. At the same time I kept my L100 in a box, and carried them with me throughout the years. For some reason it was a loudspeaker I didn't want to sell, even if I wasn't using them. Go figure.
 

Rick Sykora

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Head_Unit

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Not sure what you mean with the words 'as intended'
they'd say that the SDA...has unique spatial properties that they appreciate.
Maybe "as intended" is not a good phrase. My basic objection is that SDA/Carver/etc present crosstalk as some kind of big problem to be solved, when it is just part of the mix. What can I say, I'm an engineer, it makes me picayune :D
 
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tjcinnamon

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I gotta resurrect this thread because there's not much info. I see most everything referencing music but I'm curious how these would work with Home Theater and a Center Channel. Would the center channel "mess up" the mix?
 

mhardy6647

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I gotta resurrect this thread because there's not much info. I see most everything referencing music but I'm curious how these would work with Home Theater and a Center Channel. Would the center channel "mess up" the mix?
I would think that the "SDA" of the L800 would work at cross-purposes with a center channel -- but I have no empirical data; it's just a SWAG on my part.
You might want to ask over at the Polk forums -- although the forum s/w was just updated, and things are in a bit of disarray over there. E.g., if you're not a member, it might be a bit difficult to register right now :( That said, you can still do a search over there and see if there's any info. I don't recall seeing any discussion, though (FWIW).

The other thing you might want to consider, @tjcinnamon: there's a "private" (non-Polk sponsored) forum run and populated by once-and-future Polk fanboys where it also might be worth asking your question: https://audiomilitia.proboards.com/

ALSO :) Polk has a brand new line of loudspeakers, the "Reserve Series" that has no SDA model, but some nice looking and very reasonably priced models including large main loudspeakers and a couple of different center channel options.
 

onion

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I've found that interaural crosstalk cancellation presents sound sources in the mix as emanating at discrete points in a 3d sound-field. This is generally less fatiguing than without IACC where the sources emanate from a plane defined by the speakers' positions. There are some tracks where it sounds weird - these are usually modern pop tracks and the weirdness comes from hearing sounds below or above, to the side or behind the listening position. Even with the weirdness, it's still less fatiguing.

With stuff recorded in the studio, playback sounds like I'm listening in the studio. With stuff recorded in concert halls, it sounds like a large room. The technology seems to reduce the acoustic effects of the listening room and replaces it with the acoustic effect of the recording venue.

However, it's very true that this tech is rendering the music in a way that the producer does not hear, so it isn't 'accurate'. Still is my personal preference for most music I listen to though.
 
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