Sda 5.1

polkfan38

This is probably a dumb idea but I was wondering. Has anyone built a 5.1 (or 5.0 ) set up with SDAs? Like 1.2s for fronts and 2.3s or something similar for the rears? What center? The idea has crossed my mind more than once but I know it is HUGE overkill. But, it would be cool!
If so, how did it turn out?
Thanks

nooshinjohn

I ran 1.2TL's for fronts with LSi-15's for side/rear and tried my own sda center... then a CS-1000. Right now I have 2.3TL's with LSi-15 rear and a CSI-a6 for the center and it sounds amazing. I do not see where having SDA's as rears would be of any real benefit. If you want to be as voice-matched as possible, I would try some RTa15's or 11's in the surround spots, with SDA's up front.

Toolfan66

My personal experience is I don't like SDA's for HT But thats just me, there are a few guys on here that love it and probably taken more time to set it up then I.

I will stick with my RTiA9's for HT...

polkfan38

Is the SDA effect too "weird" for HT? With the whole separation of channels (L/C/R).
The reason I ask is that for the price of a new tower speaker, I have seen the SDAs for about the same price. Not long ago, a local guy had 1.2tls for $1,000. Besides the weight and moving problems, I would much rather have the SDAs!
And since I have you "on the line", what kind of wattage do they start to "wake up" at? My guess is that a typical AVR is not going to cut it.

leroyjr1

polkfan38 wrote: »

Is the SDA effect too "weird" for HT? With the whole separation of channels (L/C/R).
The reason I ask is that for the price of a new tower speaker, I have seen the SDAs for about the same price. Not long ago, a local guy had 1.2tls for $1,000. Besides the weight and moving problems, I would much rather have the SDAs!
And since I have you "on the line", what kind of wattage do they start to "wake up" at? My guess is that a typical AVR is not going to cut it.

I never liked SDA's for HT because IMO for HT I look for a speaker(s) that is forward, clear, and dynamic with also alittle detail up top. I would classify the SDA's as having a laid back midrange, not dynamic and being a little slow.

For 2 channel they're better.

heiney9

I have a 2 channel set-up with SDA 1C's and I also watch movies on my 2 ch. rig. SDA's are great for watching movies. They will never replace a true 5.1 system, but I've had many people ask me where the other speakers are or where the sub is.

The sub-bass and clarity is stunning with a properly set up pair & with proper electronics. So I disagree with Leroy about them not being dynamic, clear and detailed. The electronics have a lot to do with this however. If you are going to run an AVR then just get RTi's or TSi's or whatever because an AVR won't do SDA's justice and it would be a huge waste.

I'd say an SDA 5.1 is overkill and not the best use for SDA's. But, it's your money, your listening room, etc.

falconcry72

I love SDA's for HT, but they need to be set up properly. The front soundstage is awesome, and they make the sides or rears sound very integrated since the fronts throw sounds so far to the sides.

The only way to use SDA's as rears is to have them mirror the fronts. They can't be sides, only rears. They should be about as wide apart as the fronts, parallel to the rear wall, and just as far back from the seating position as the fronts are forward of it. You have to have a unique room/seating setup to do this properly, otherwise you will not get good results. Setup properly, however, you will get an incredibly enveloping sound field, with the fronts and rears both throwing sounds to the sides.

I don't have a space where I can use SDA's as rears, so I use RTA-12C's as sides. They match my SDA-2B fronts perfectly in both timbre and hieght. They sound great! I use a CS-350ls as a center, but I'd like to try a SDA-CRS+ wired to have both MW's in stereo as a center, then I could use the other CRS as a rear center if I wanted.

I recently went back and forth between these vintage Polks for HT and a set of more modern Polks which included RT-16's as fronts, RT-7's and sides, and the same 350 as a center wich matched those speakers perfectly. I went vintage, sold the more modern Polks, and haven't looked back. I main reason for this is that I use my HT setup for music most of the time. Either listening to music in surround sound or watching concert DVD's, and I prefer the vintage Polks for music.

Both systems did great on movies, though were very different from each other. I like SDA's as fronts.

heiney9

Another thing with properly set-up SDA's is the phantom center is superb. No need for a center channel at all.

H9

P.s. Of course I sit in the sweet spot.

newrival

nooshinjohn wrote: »

I do not see where having SDA's as rears would be of any real benefit.

Up until a week ago I had been running my HT with SDA's. I was using the configuration as described by SRS's for the mains and CRS+ for the rears. I have it set up n the 6.1 configuration that Stu Lumsden (VP of Engineering at Polk) suggested on this very forum.

His credentials, in his words: "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."

His statement on the issue: "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. "

I dont quite understand why you feel there would be little use for SDA for the rears. It is the same principle. It is not like the physics of hearing change because the sound is behind you.

Perhaps you don't disagree with the theory, and you you just havent had good results in practice. Then I would suggest that you remember that the same rules apply to SDA's in the back as they do in the front. The distance froom the vertical plane of the speakers to the listening position must be greater than or equal to the distance between the speakers. Additionally, you need to remember that the sda driver needs to stay to the outside so the right rear channel needs the "left" SDA speaker and the left rear channel needs to be the "right" SD channel.

I can attest that this is a very nice setup for HT. The one caveat is that the SDA cancellation loses its effectiveness the wider the seating gets. 4 seats wide and 2/3 seats deep may be as far as you want to go. But for mos that is more than sufficient.

And to the other OP point. Monitor 10's, 5's or similar, CS400, CS1000p, (NOT the CS350), or anything that utilzes the same(ish) compliment of drivers can make for a good center. I actually used monitor 10b's with sl2000 tweeters before finding CS1000p's for the front and rear center.

newrival

by the way the CS350 comment is in my opinion. it may work out very well for falconcry. His post wasn't up yet when I started typing.... Anyways, the CS350, while a very fine speaker, is quite a ways off in timbre. It is ultra clear and one of the best center cannels ever produced by polk. However, the timbre is just not close. Its much more forward and lighter. After trying over a dozen different center choices, of the more modern centers, the CS400 and CS1000 are the best, due to (IMO) the similar use of 6.5" drivers as opposed to the 4" (IIRC) in the CS350's

heiney9

SDA sort of becomes a moot point in the rears if you are running a processor because they aren't being fed the full 2 channel signal, which is what SDA's were designed around. Not saying it won't work but all that you (newrival) outlined in the above post is greatly diminished because of lack of a "full" audio signal.

Discuss............

H9

mhw58

I have SDA's in my HT setup and LOVE them! I have 1C's as fronts, 2's as my rears with a CS400i center and a Polk 505 subwoofer. All my friends love my system. Watched 'Inception' last night and it was fantastic! The SDA's make the music in movies sound fantastic. I love watching music dvd's that are mixed in 5.1 like Steely Dan etc.

Mike

newrival

polkfan38 wrote: »

The idea has crossed my mind more than once but I know it is HUGE overkill. But, it would be cool!

I don't think that it is overkill at all. Their monolithic appearance can be intimidating, but they are quite refined, and able to sound very delicate. But then again, theyll leave you a collapsed bloody mess if you ask them to :biggrin:

nooshinjohn

newrival wrote: »

I can attest that this is a very nice setup for HT. The one caveat is that the SDA cancellation loses its effectiveness the wider the seating gets. 4 seats wide and 2/3 seats deep may be as far as you want to go. But for mos that is more than sufficient.

and that is why, for me, SDA's don't work for the rear.... It's not that they can't, rather that for most of us, being able to get a seating arraingement where they can be most effective is just too much of a challenge.

Joe08867

heiney9 wrote: »

SDA sort of becomes a moot point in the rears if you are running a processor because they aren't being fed the full 2 channel signal, which is what SDA's were designed around. Not saying it won't work but all that you (newrival) outlined in the above post is greatly diminished because of lack of a "full" audio signal.

Discuss............

H9

I agree the amount of audio info sent to the rear speakers is diminished or limited in comparison to the fronts, but wouldn't the SDA effect open up the rear soundstage enough to envelope you in sound better than regular 5.1?

Isn't this the reason why they make dipoles for rear speakers?

leroyjr1

heiney9 wrote: »

I have a 2 channel set-up with SDA 1C's and I also watch movies on my 2 ch. rig. SDA's are great for watching movies. They will never replace a true 5.1 system, but I've had many people ask me where the other speakers are or where the sub is.

The sub-bass and clarity is stunning with a properly set up pair & with proper electronics. So I disagree with Leroy about them not being dynamic, clear and detailed. The electronics have a lot to do with this however. If you are going to run an AVR then just get RTi's or TSi's or whatever because an AVR won't do SDA's justice and it would be a huge waste.

I'd say an SDA 5.1 is overkill and not the best use for SDA's. But, it's your money, your listening room, etc.

That's the great thing about this hobby. There's hundreds of speakers out there to fit everyone's taste and budget. Best thing for the OP is the have a listen and get the experience first hand.

heiney9

If you have the real estate, power, WAF and can really properly set them up, I say go for it. But if you dont have all of the above, then just stick to RTi's or TSi's and be done with it.

With a smallish room, placement compromises, low WAF, inexpensive gear, I'd say not worth using SDA's as a 5.1. I can imagine them being formidable in about 5-10% of all HT set-up's because of the above I've mentioned caveats.

I still am of the opinion it's not the best use for SDA's (as in rear surrounds)

H9

heiney9

Joe08867 wrote: »

I agree the amount of audio info sent to the rear speakers is diminished or limited in comparison to the fronts, but wouldn't the SDA effect open up the rear soundstage enough to envelope you in sound better than regular 5.1?

Isn't this the reason why they make dipoles for rear speakers?

Depends, later SDA's had a very limited range for the SDA drivers. There is quite a design difference between early production SDA's and later production SDA's so that will vary as well depending on which SDA model's one uses.

H9

Joe08867

heiney9 wrote: »

Depends, later SDA's had a very limited range for the SDA drivers. There is quite a design difference between early production SDA's and later production SDA's so that will vary as well depending on which SDA model's one uses.

H9

I had forgotten that. How about this scheme for instance.

SDA2's for front, SDA CRS for rears and CS400 for center. Maybe even a CS400 for rear center for 6.1 which is what I have and prefer. And a PSW for a sub.

newrival

heiney9 wrote: »

SDA sort of becomes a moot point in the rears if you are running a processor because they aren't being fed the full 2 channel signal, which is what SDA's were designed around. Not saying it won't work but all that you (newrival) outlined in the above post is greatly diminished because of lack of a "full" audio signal.

Discuss............

H9

Ahhhh, a valid point when you lay it out like that... I have no intimate knowled on the mix-down practices of surround tracks, but it would seem to me that they would still be done in a similar fasion, The exception being that instead of a stereo pan youre also dealing with a z-axis fader. As such, some amount of the signal in one channel is always present in a neighboring channel. It becomes a matter of how much. This being so makes the case for SDA in that it would cancel the crosstalk of one rear to the other. Even if that amount is not huge, it's effects are still apparent in broadening the rear soundstage. In my experience, it has been the most enveloping sound I'd ever encountered.

newrival

heiney9 wrote: »

Depends, later SDA's had a very limited range for the SDA drivers. There is quite a design difference between early production SDA's and later production SDA's so that will vary as well depending on which SDA model's one uses.

H9

Can you explain what you mean by "had a very limited range"

Conradicles

I run SDA-2B's as my fronts in my 5.1 small H/T rig and love them. I run no sub-woofer (how many folks can say that), and turn up the bass a bit in the lowest frequency after running the room correction EQ.

Works perfect for me since a listen at lower to moderate levels, and hardly ever crank it up.

Joe08867

I believe what he means is Polk tailored the crossover point of the SDA signal to a very narrow bandwidth in later models. Especially true in the larger systems, 3.1TL, 2.3, 1.2TL's.

Not sure how much they changed the crossovers in the 1's and 2's.

heiney9

newrival wrote: »

Can you explain what you mean by "had a very limited range"

As Polk developed SDA technology they found they could narrow the band of frequency sent to the dimensional drivers and it actually improved the perfromance.

I could outline each model and how they function, but I don't have the time and it's been outlined here before.

Early SDA's had side by side tweets and one tweet was fed the SDA signal. That was later eliminated (for the better in my mind) but the dim drivers were still sent a full signal

At some point starting with the 1C's they simplified the x-overs and realized SDA's could be just as effective if they limited the freq band sent to the dimensional drivers. This also led to a little more friendly impedance curve compared to earlier SDA's.

All SDA's present a more complex load because of the SDA inter connect and it taxes the negative side of an amplifier even though the impedance and sensitivity of the the later SDA's was better.

H9

leroyjr1

Conradicles wrote: »

I run SDA-2B's as my fronts in my 5.1 small H/T rig and love them. I run no sub-woofer (how many folks can say that), and turn up the bass a bit in the lowest frequency after running the room correction EQ.

Works perfect for me since a listen at lower to moderate levels, and hardly ever crank it up.

Have you ever tried running a sub? Seems you'd be missing alot of the low end impact/punch when not using a sub.

heiney9

Joe08867 wrote: »

I believe what he means is Polk tailored the crossover point of the SDA signal to a very narrow bandwidth in later models. Especially true in the larger systems, 3.1TL, 2.3, 1.2TL's.

Not sure how much they changed the crossovers in the 1's and 2's.

2B's and 1C's were the same as the larger later SDA's. They had the simplified x-over with limited bandwidth for the dim drivers.

see this review as it explains it (the 2nd column)

http://www.polksda.com/sda1creview.shtml

H9

heiney9

leroyjr1 wrote: »

Have you ever tried running a sub? Seems you'd be missing alot of the low end impact/punch when not using a sub.

People say this all the time. I can rattle the pictures on my walls watching a movie with no sub using the 2.0 setting on the dvdp and just running my 1C's. No sub needed.

Of course I have an amp with the balls to do that.

H9

newrival

H9,

I understand now. I read it too quickly and thought you were asserting that SDA's had limited frequency response. My mistake.

newrival

heiney9 wrote: »

People say this all the time. I can rattle the pictures on my walls watching a movie with no sub using the 2.0 setting on the dvdp and just running my 1C's. No sub needed.

Of course I have an amp with the balls to do that.

H9

I would think you'd gain a little coherence and clarity if you moved to a sub for the LFE. I agree your 1c's like my SRS's have no trouble reaching the depths, but I found that after I relieved my SRS's of handling the the LFE channel the sound was a bit more clear and sound effect were clearer and there was a better separation of the SFX from the music and dialog.

newrival

Joe, how big is your room? Don't be afraid to to get the SRS's I think any of them are fantastic and worth the extra ching. Then you can just select which SRS's ou get based on room size. The 2b's would make good rears, just make sure you match all the tweeters.

heiney9

newrival wrote: »

I would think you'd gain a little coherence and clarity if you moved to a sub for the LFE. I agree your 1c's like my SRS's have no trouble reaching the depths, but I found that after I relieved my SRS's of handling the the LFE channel the sound was a bit more clear and sound effect were clearer and there was a better separation of the SFX from the music and dialog.

Well for me I have a simple 2 channel system, so no LFE to process. I am 99% music and 1% movies. When I have space available I will have a completely separate HT rig which will probably be and AVR, RTi's and a Micro-Pro sub.

For now the SDA's with a simple 2ch system sounds better than they should when watching movies.

H9