Some SRS/SDA Questions

cobramatteo

Hello All,

I currently work as a civilian adviser for the US Army in Afghanistan. After 4 years of working in Iraq previously, I started buying up all the audio equipment I lusted after while in Bamburg, Germany as an Army brat. [I am 35 now]

Over the past year I have bought and am keeping in storage till my return to the US in 11 months :

2 pairs SRS 1.2s, 1 pair SRS 2.3s, 1 pair SDA1s, 1 pair CRS - My goal is to have all of the crossovers recapped, upgrade the tweeters, restore the finish [or have all new veneer of the same color put on all the speakers], perform all the basic tweeks that this forum thinks are worthwhile.

As for power, I will be going with about 10ea Adcom GFA555s, that will all be recapped and gone through. I may end up just buying a Cinepro 3k6 to drive them.

Some questions I have are :

1. Who should I get with to go through all my crossovers and get the steel rings for anchoring the drivers ? I would prefer to send the crossovers out have them all updated over the next year.

2. I would like to use this equipment in a 7.2 setup - well most of it anyways, if not using the SDA link, do all the drivers function, or will their be some [dead] drivers? I fully intend on using the SDA link when possible.

3. Does Polk still offer all of the drivers and tweeter replacements, if so how much each ?

I appreciate all your feedback, and have nothing but time over the next 11 months to get up to speed on all things SDA/SRS.

Thanks

Matteo

phocion

A. Welcome to Club Polk! I am jealous of your collection and I hate you.

1. TOOLFORLIFEFAN (http://www.polkaudio.com/forums/member.php?u=94850) has done runs of rings in the past. Not sure on the x-overs, seems like most people do their own, but I am sure someone else can chime in on this.

2. SDA is probably a waste in 7.2, since the sound stage for movies is prescribed by the number of tracks instead of the usual stereo affair. My understanding of SDA technology (admittedly sparse) is that the interconnect cable produces out of phase sound in the opposite speaker, which will make for odd listening in 7.2. I have my 1C's in a 7.1 setup, which works fine, but I can't really tell you what would happen if all your speakers were interconnected in pairs. It might open a sonic black hole and tear the Earth in half. Generally, the SDA effect is for music, and a lot of the people on here are 2 channel purists. I think that all the drivers work regardless of the presence of a cable, but I am not sure.

3. Yes, and they will give you a discount for being a CP member. Tweeters (RDO-194's) are ~$48, not sure on the mid woofer price, but I think it is about the same. You can call Polk to get the discount and order. It is generally recommended to replace all the tweeters at the same time, which could get expensive, so if you have bad tweets you might want to match them between models (matching sl2000 to sl2000, for instance)to replace the fewest parts.

Cheers and welcome! There is a ton of info on these boards, so you should have plenty of info to while away the hours.

audio_alan

Regarding point #2, I believe the SDA drivers will NOT work if you don't have the interconnect cable plugged into the speakers. Someone please correct me if I'm wrong, but I'm fairly certain that's the case...

halo71

^ I think you mean the SDA "effect" won't work without the IC.

nadams

halo71 wrote: »

^ I think you mean the SDA "effect" won't work without the IC.

It depends on the SDA's. My original 2's drop the SDA drivers altogether when you don't plug in the interconnect.

heiney9

audio_alan wrote: »

Regarding point #2, I believe the SDA drivers will NOT work if you don't have the interconnect cable plugged into the speakers. Someone please correct me if I'm wrong, but I'm fairly certain that's the case...

Depends on the model and generation SDA.

the 1.2's and 2.3's will most likely play some low frequency signal when the cable is unplugged in the dimensional drivers.

the 1's depending on if they are original or A's or B's or C's will either play some low frequency material or nothing at all in the dimensional drivers.

crs's depends on if they are crs or crs+'s and if they are crs+'s are they 87 or 89 models. They might play some low frequency material or nothing at all in the dimensional drivers.

It's my strong opinion that if one is really not using SDA's with the interconnect cable it's best to sell them and get a conventional speaker. It's a waste of a speaker to use them other than intended.

It's sort of like buying a Corvette to drive to the end of your drive-way to get your mail everyday. I know....extreme analogy but you get the idea.

It's also my strong opinion SDA's perform best in a 2 channel rig not a HT, but that's just me. Not that they can't do HT, again a waste of a great speaker.

H9

phocion

See, I knew that someone here would have the goods. Thanks Heiney9, as usual with classic Polk, there is no easy answer

audio_alan

heiney9 wrote: »

... <snip><snip> ...

It's also my strong opinion SDA's perform best in a 2 channel rig not a HT, but that's just me. Not that they can't do HT, again a waste of a great speaker.

H9

Heiney9 - Thanks for the detailed explanation of performance without the interconnect cable. Good to know.

However, I'm puzzled why you consider them a waste in a HT setup. Wouldn't the technology of eliminating crosstalk transfer perfectly to the Fronts in a 5.1 or 7.1 setup? Is your statement based purely on how often you would actually benefit from that extra separation (since the center channel does most of the heavy lifting in a lot of movies - especially comedies)? If so, watch more sci-fi!

Personally, I have a pair of 2.3's as the fronts in my Home Theater. I think they sound awesome! Then, if I want to listen to music, I can switch to Pure Direct and listen to them in 2-channel mode. The best of both worlds. ***(Although, having said that, my SDA-SRS's are going to be upstairs as my new 2-channel rig...)

mmadden28

Are you planning on only having the fronts connected with the SDA interconnect??Are you going to be the only one watching movies? The SDA sweet spot is not that big, so anybody else might miss out.

HT, esp surround sound, sends a discreet signal to each speaker to get the desired effect. Throwing the SDA 'effect' in there along with all the other discreet signals going on from the surrounds and backs, sounds like it might be a sonic disaster like phocion mentioned (not that I tried it). Also keep in mind that SDAs shouldn't be 'toed in' and require very specific placement to work as designed, and that's just a 2 channel setup-I can't imagine where you would begin to setup a 7 SDA speaker rig, or how the center channel would fit in.

Polk has already released a series of speakers with SDA tech for HT use (along with other similar designs from other companies) but that is generally a single front speaker along with a sub. Although one of the yet-to-be-released designs has a rear speaker which I am looking forward to hearing a demo of the final product.

I agree with H9, if you're main focus is a HT setup with a 2 channel option, maybe you should look into the new Polk LSiM lineup due out early 2011 - an apparent top notch choice for HT or 2 channel. Save the money you would otherwise put into upgrading the vintage models and get the LSiM's. Of course upgrade these if you still want to, but I wouldn't do it to make them all part of a 7.2 setup.

Oh yeah, welcome to Club Polk

bluecomet

I tend to agree. I have many SDA speakers and I prefer to use them in a two channel setup instead of HT. I enjoy my Lsi speakers for Home theater movies. SDA's were never intended for HT. I have used them and I feel they are lacking that special sound when the IC is not being used. Just my experience.

audio_alan

mmadden28 wrote: »

....

HT, esp surround sound, sends a discreet signal to each speaker to get the desired effect.

...

Besides being more channels and more content, I disagree that 5.1/7.1 is more discrete than Stereo. If you were to decode a 5.1 track, you'd see that dialog is mainly in the center, music (and effects) are in the Front L/R, and occasionally you get effects in the surrounds. How would the Fronts in a 5.1 track (playing a song) differ from a 2-channel rig (playing the same song). Not by much probably.

The main advantage of SDA speakers is to eliminate crosstalk, affecting how you perceive the material. If a 5.1 soundtrack wanted a plane to fly from the left front to the rear right, SDA would make the plane sound like it's more distinctly in the left front, converge in the center, and disappear in the rear right. I only see that as a benefit. Perhaps I'm wrong. It would be interesting to do some blind tests...

mmadden28

XO upgrades:
~300-500 for each XO pair to be recapped (more or less depending on the type caps you want and how crazy you want to get-some can be quite expensive)
Contact member 'Face' or 'ben62670' about possibly doing the XO upgrades for you.

Rings:
~$120 for each pair set of 1.2 rings
~$100 for each pair set of 2.3 rings
~$75 for each pair set of 1 (a/b/c) rings
~$50 for each pair set of CRS rings
~6 for each tweeter bracket set

Tweeters:
About $45 each from Polk. That's a lot of tweeters.

Drivers:
I'm not familiar with whats available but some of the drivers can still be bought from Polk, but I think some are not so you'd have to rely on the used market. I think drivers range from $15-$50 each depending on model, condition and whether used or new.

Veneer/new tops/bottoms:
?? No idea, but can't be cheap.


Other:
Dynamat the driver baskets - probably ~$150 (for all) depending on how much you need.
Mortite or similar for the driver seals, $10-$50 (for all) again depends on what you use if anything
Binding posts: ~10-80 per pair (+ more if you upgrade the Interconnect post as well) Optional
Interconnect cables (if you need them, or want to upgrade them) ~$35 each
Spikes: ~$10 each spike
Add in shipping and labor charges and you have one heck of an upgrade cost.

(All of the above estimates are complete SWAGs-I could be way off).

cobramatteo

Well everybody, thanks for all of your insights. I have bought many many speaker sets while working in the middle east, and all are waiting on me in storage till my return.

[4 sets of Klipsch KG series- the big 4.2/5.2s, 1 set of Klipsch Chorus, 4 sets of black Bose 901s series six, my polk SDAs mentioned above, 2 sets of Magnapans, 4 sets of 901 series 1, 2 Sunfire signature subs, 2 sets JBL 4312As].

It looks like I will simply use my polks for a great 2 channel setup as intended and probably use the Klipsch KGs in my dedicated HT rig.

I personally like the way 901s sound given ample room and plenty of power and have always wanted to have a HT consisting of them, so those will probably be in a secondary system with powered subs as well. Call me crazy - lol.

I went a little overboard on Ebay last fall buying up equipment, and will cherry pick my favorite pieces and resell the remaining gear online.

My only thought was that used in a muti-channel setup with the SDA link, most processors have a stereo feature running 2 channel to all speakers. So I could still listen in stereo and then switch in to theater mode for movies. Was looking into the new Emotiva suround proc., it seems to be well made, and pretty cheap at 699.00 ea. With tech changing so fast, I do not want to invest too much into my processor just to have it outdated in a few years - plus Emotiva even lets you trade up on the newest gear.

Amps will primarily be various Adcom's about 16ea, with 4ea Carver M400s


I will likely be buying 3 processors so paying 10k ea for the newest McIntosh seems a little overkill.

Thanks again for all of your help.

audio_alan

Lasareath wrote: »

When I had my 1.2TL's in a HT setup they sounded great!

Woohoo, another believer in SDA-HT! Each to their own though, I suppose...

But, back to the original poster's questions, upgrades are most dramatic in the following order...

Cross-overs (get rid of those old caps!)
Upgraded tweeters (people who like the new tweeters rave about them)
Dynamat, Rings, Mortite.
Wood replacement/fixing, cloth replacement (aesthetics only)

... refer to mmadden28's post for pricing.

audio_alan

cobramatteo wrote: »

... My only thought was that used in a muti-channel setup with the SDA link, most processors have a stereo feature running 2 channel to all speakers. So I could still listen in stereo and then switch in to theater mode for movies. ...

That's what I do. Try it. You have nothing to lose (well, unless you don't have a common ground amp, in which case you'll damage your speakers and/or amp). If you find the SDA effect objectionable for surround sound, switch out your speakers. If you like it, enjoy your SDA speakers in both listening modes...

NOTE: SDAs should NOT be used for side surrounds because they can't be setup parallel to each other (as the documentation specifies). Only fronts (5.1/7.1) and rear surrounds (in 7.1) can even be considered for SDAs.

mmadden28

audio_alan wrote: »

..., I disagree that 5.1/7.1 is more discrete than Stereo. ... How would the Fronts in a 5.1 track (playing a song) differ from a 2-channel rig (playing the same song). Not by much probably.

The main advantage of SDA speakers is to eliminate crosstalk, affecting how you perceive the material. If a 5.1 soundtrack wanted a plane to fly from the left front to the rear right, SDA would make the plane sound like it's more distinctly in the left front, converge in the center, and disappear in the rear right. I only see that as a benefit. Perhaps I'm wrong. It would be interesting to do some blind tests...

I didn't say 5.1 was more discreet--5.1 surround is discrete, just as 2 channel is-unless you're using a processing option in the AVR to simulate surround from a non surround encoded source. The AVR decodes the surround signal from the source and sends each channel only what it's supposed to play. The sound engineers for the movie, etc decide what to send where, at what volume relative to the other channels, an with specific timing delays in order to get the appropriate audible ed result, hence the ratios of dialog, music and surround effects, oh and the LFE as well--All Discreet channels.

SDA's eliminate cross talk by having each speaker (L&R) cancel out the crosstalk of the other speaker (and only the other speaker) to get true stereo (as you would essentially have in a set of headphones), not to make a surround sound system (if so then you wouldn't need surround speakers would you?). With traditional vintage SDA speakers you are dealing with only 2 speakers.

I would imagine in a 5.1+ SDA setup that the dimensional signal could either cancel out some of the audio from the surround speakers and perhaps even amplify signals of the same phase, etc from a surround speaker (or vice versa if the surrounds are also configured with the SDA interconnect in play) (I could be wrong on this assumption). The AVR is simply not equipped to figure that into the equations and still end up with the surround effects as the engineers intended. The Polk Surround bars were specifically engineered to simulate surround sound from the one front speaker, the Vintage SDA's were not engineered for HT (wrt modern surround HT).

I think a good example of how the interference can happen is when you setup 2 subs in a system and if they are not tuned just right, they can either cancel each other out or dip in certain frequencies and/or bump/amplify in certain frequencies, esp. if there is a phase issue. Same for a single sub setup and trying to match them to the main speakers.

Bottom line, why add so much complication to the mix for unknown results?

mmadden28

Lasareath wrote: »

When I had my 1.2TL's in a HT setup they sounded great!

How were they setup?
Just the 1.2TLs?
Did you have surrounds? Were the surrounds also SDA?
Center?
Were you playing a surround mix (encoded for 5.1) or from a stereo mix letting the SDA's simulate the surround effects?

mmadden28

cobramatteo wrote: »

...
[4 sets of Klipsch KG series- the big 4.2/5.2s, 1 set of Klipsch Chorus, 4 sets of black Bose 901s series six, my polk SDAs mentioned above, 2 sets of Magnapans, 4 sets of 901 series 1, 2 Sunfire signature subs, 2 sets JBL 4312As].
....
I went a little overboard on Ebay last fall buying up equipment, and will cherry pick my favorite pieces and resell the remaining gear online.
...
Call me crazy - lol.

...

Your CRAZY!!! :rolleyes:;)
I understand what you mean about going a little overboard on eBay. I did that last year too and ended up with way way more than I ever needed.

Did you get the Polks via eBay as well? Did you have them shipped or were they all local deals?

audio_alan

mmadden28 wrote: »

... The sound engineers for the movie, etc decide what to send where, at what volume relative to the other channels, an with specific timing delays in order to get the appropriate audible ed result, hence the ratios of dialog, music and surround effects, oh and the LFE as well--All Discreet channels. .....

Bottom line, why add so much complication to the mix for unknown results?

Perhaps when all speakers are playing the exact same sound at various levels, to move a specific sound around the room, then maybe you would have a problem with using a set of SDA speakers. However, during 95-99% of most movies, you hear dialog from the Center, music or effects from the Front L/R, and different effects from the Sides/Rears. You shouldn't have any cancellation anomolies, and I have noticed none. With all due respect, I think you are thinking more about the theoretical nature of surround sound, and not what most sound engineers actually mix.

It sounds like we should agree to disagree. Besides, we are derailing the original thread (sorry cobramatteo). Mmadden28 - if you would like to continue this discussion, maybe we should start a new thread, or take it private.

Oh, and bottom line, I have no complications. I setup the speakers and it sounds great. That's what matters in the end, right?

cobramatteo

mmadden28 wrote: »

Your CRAZY!!! :rolleyes:;)
I understand what you mean about going a little overboard on eBay. I did that last year too and ended up with way way more than I ever needed.

Did you get the Polks via eBay as well? Did you have them shipped or were they all local deals?

Yeah, I just saw so many good deals, I just kept buying and buying - knowing that I can later resell whatever equipment I did not use for what I paid or better.

I bought my first pair of SRS 1.2s from Ebay, got them for 1500.00 and shipping was 600 from California to Michigan.

The second pair I am currently buying from Hamatyme on this forum [ tweeters have already been upgraded] and he is delivering them to Michigan from Ohio for 1300.00 - A steal compaired to my first set lol.

The SDA 1s were bought off Audiogone for 500.00

The SRS 2.3s were local from Craigslist for 600.00

The funny thing is, I do not even own a house right now being that I have spent the past 5 years working in Iraq/Afghanistan - I am saving now and will be buying a house large enough for 3 HT systems and a nice 2 channel setup.

cobramatteo

Lasareath wrote: »

Hey Cobra, What do you have in the way of cables? Any MIT's?

No cables yet, I thought about buying the parts off Ebay and soldering my own RCA interconnects from solid silver parts instead of paying the crazy prices that are out there.

BTW, I have seen your great restoration/mods you did to your 1.2s and would eventually like to bring all of my SRSs to that level of performance

mmadden28

audio_alan wrote: »

Perhaps when all speakers are playing the exact same sound at various levels, to move a specific sound around the room, then maybe you would have a problem with using a set of SDA speakers. However, during 95-99% of most movies, you hear dialog from the Center, music or effects from the Front L/R, and different effects from the Sides/Rears. You shouldn't have any cancellation anomolies, and I have noticed none. With all due respect, I think you are thinking more about the theoretical nature of surround sound, and not what most sound engineers actually mix.

It sounds like we should agree to disagree. Besides, we are derailing the original thread (sorry cobramatteo). Mmadden28 - if you would like to continue this discussion, maybe we should start a new thread, or take it private.

Oh, and bottom line, I have no complications. I setup the speakers and it sounds great. That's what matters in the end, right?

I see what you're saying about the probability of cancellations with respect to the different signals at each speaker-makes sense, but the probably still exists no?. Multichanel systems are also not just for movies, they are also for audio only such as DVD-A and SACD with surround and much more use (if not equal to the L/R) of the surround channels, so the probability of potential cancellation increases, no?

So let's forget about the probability of cancellations from the surrounds but think more about the sound stage and imaging. The SDA effect (when setup correctly) does change the sound stage and imaging vs. standard stereo speakers (agree?) and I don't think the audio engineers accounted for that when determining how they should pan a sound to simulate an airplane flying overhead, and that has to have some affect on the end result of what the engineers intended the viewer to hear, no?. What about the center imaging--I find it amazing how my SDA's place most vocals dead center. That's not going to impact the end sound when audio is also coming from the actual center channel?

I'm glad your happy with your setup and yes that is what matters in the end, but what is satisfactory for one is not always good for the many-and this would not be standard or as designed--I've seen quite a few setups that were just insane (4 center channels, 2 lefts and 2 rights, etc, etc.-you get the idea) but they were perfectly content with the end sound, or some might be perfectly content with the 'Hall' effect from their AVR for everything.
If the OP is going to dump a boatload of money into upgrading his speakers (prob. enough to buy a full set of new TOTL speakers), is it really the best advice to say absolutely go for it because you or a few others have done it with relative success? We don't even have any details on exactly how he intended to set them up (center, what speakers where, with SDA on all or just fronts, multichannel SACD, etc).

How is your SDA HT system setup? SDA/interconect only on L&R and/or rears?? Are you using a center channel speaker or a phantom center? I'm genuinely curious about this.

I don't think our discussions are really derailing the thread as it was one of the original questions mentioned, and esp. if it helps the OP decide what to do (or to avoid potential issues) in the end. If I'm mistaken and the OP finds no value in the discussions then I apologize to the OP.

For all I know a full blown surround setup can be achieved with all SDA's with perfect results and be that magic fill-the-audio-surround-gaps solution without going with a 10-12 speaker setup, and that would be great. But my guess would be that's not fully possible, or would require more work than would be reasonable or at the very least result in some kind of sacrifice in multi-channel audio accuracy. And if not using all or any of them them for the SDA effect (as in not using the interconnect) would be as H9 originally stated, a waste of great speakers.

mmadden28

cobramatteo wrote: »

Yeah, I just saw so many good deals, I just kept buying and buying - knowing that I can later resell whatever equipment I did not use...
...

That was my mistake, yet I still have everything (well I sold one set at my wife's gentle DEMAND )

F1nut

You're going to spend a lot of money and time upgrading your SDA's and you're thinking Adcom and Emo gear!?! You might want to think about that move again.

cobramatteo

Lasareath wrote: »

Yes, you need some Bat amps!

http://www.audiogon.com/cgi-bin/cls.pl?ampstran&1290708413

I have seriously considered selling most of my lower end equipment and buying McIntosh separates both new and used. I have always liked Mac stuff and think going the Quality over Quantity route might be the best route to take.

Gonna keep the Carver M400s though, those 4 are being sent to Bob's own shop to be rebuilt and signed by him.

cobramatteo

F1nut wrote: »

You're going to spend a lot of money and time upgrading your SDA's and you're thinking Adcom and Emo gear!?! You might want to think about that move again.

I am starting to lean towards buying all McIntosh gear, so let me know of any great deals you hear about - lol.

cobramatteo

The statement above was only referring to power amps and preamps, not my beloved Polks - those will be mine - FOREVER !:rolleyes:

helipilotdoug

cobramatteo wrote: »

I have seriously considered selling most of my lower end equipment and buying McIntosh separates both new and used. I have always liked Mac stuff and think going the Quality over Quantity route might be the best route to take.

Gonna keep the Carver M400s though, those 4 are being sent to Bob's own shop to be rebuilt and signed by him.

I'd think about Sunfire too. You can find some really good Sunfire pre/pro and amps out there.