SDA SRS 2 speakers

drgalexo

I recently acquired a pair of polk SDA SRS 2 speakers. I am powering them with Denon POA 6600 monoblock amps with 250 wpc. I have a major problem when I try to connect the interconnect cable between the two speakers. It is a new cord I just purchased from Polk. The speakers sound fantastic even with out the interconnect but I am wondering what I am missing, other than two blown speakers or amps.

jimbo1421

All SDA speakers require a common ground amp. That is, there should be continuity between the negative speaker terminals. Monoblocks by design are not common ground. Possibly you can strap the negatives together or use the AI-1 interface. You can download manuals for other SDA models from http://www.polksda.com/manuals.shtml to get a better idea of how to set them up. Meanwhile, do not use the interconnect cable until you have resolved the common ground issue or you will end up with "two blown speakers or amps".

Jim

drgalexo

Thanks for the imput, unfortunately it's what I was afraid of, they actually sound wonderful as they stand and I'm tempeted to leave well enough alone. I do have the opportunity to return the Denon amps and get an integrated amp, but I'm not sure if the interconnect cable is that significant.

jimbo1421

The interconnect cable is essential to produce the SDA effect. To understand what that read this:

http://www.polkaudio.com/downloads/tech-briefs/SDA_WhitePaper.pdf

Once I heard SDAs properly set up I have not wanted to go back to plain old stereo.

Jim

drumminman

Welcome to CP! Once you get those properly set up, i.e. with the IC cable connected you'll understand why SDA speakers are so sought after.

But. . . . . . .you need to contact the manufacturer to determine if you can strap the negative binding posts on each amp together. IOW take a length of speaker cable and connect them. That will enable you to use those amps without damaging anything.

A better solution is to build an AI-1 interface using a high quality toroidal transformer. Not hard at all. In face Nspindal is running a group buy right now that you may be able to piggy back onto which can be found here:
http://www.polkaudio.com/forums/showthread.php?134643-Group-buy-Avel-Lindberg-1000VA-isolation-transformers-for-DreadNought

Darqueknight has a great DIY thread with pics on how to build these. The AI-1 is an elegant solution that makes even common ground amps sound better.

drgalexo

Well I guess I'm just going to have to get that interconnect cable working after all. Thanks for all the great info and resources.

drgalexo

In my attempt to appreciate the effect of the SDA with the interconnect cable, I used a Kenwood reciever I had which would eliminate the common ground problem I was having with the Denon POA 6600s. I was listening with and with out the interconnect cable, plugging it in for a period and then with out. I really couldn't hear any difference with or without the cable. At one point however, something wasn't right with the left channel so I shut everything down, and reconnected the Denon monoblocks, and although they made a huge difference in the sound, something is clearly blown in the left speaker. Now ofcourse I have a real problem. I'm not sure what is wrong with the interconnect cable and these speakers but I wish I had left well enough alone. I[m not sure what is wrong with the speaker but it doesn't resonate properly at a very specific bass pitch, it is fuzzy, everything else seems ok. It's very noticeable with Diana Krall's CD with certain bass notes. Large, heavy speakers, and difficult to transport. Now I really have a problem, I'm not sure the interconnect cable is ever going to work properly if there is a problem with a reciever supplying the power with no common ground problem.

GlennDog

drgalexo,

It can be a bit much to absorb all at once. Take your time and get your read-on with the above mentioned threads. I also have SRS 2s and they sound great (fantastic even). You wont regret spending some time getting them working properly

btw, where are you located? And welcome to CP!

G

evhudsons

Very important, check to see if yours are blade blade or pin blade, because otherwise you may still have damage even if you strap the negatives together. From what I have read on the forum here, the blade blade like mine can't use monoblocks or the a1 interconnect. I don't know why but these guys know their stuff. If it's pin blade, then you can.

Hopefully you'll figure it out, because you have one awesome set of speakers and haven't actually heard them yet.

Welcome to Club Polk! You came to the right place.

jimbo1421

You can run these diagnostic tests (scroll down to post #9):

http://www.polkaudio.com/forums/showthread.php?55888-POLK-AUDIO-Speaker-Wiring-Schematics-amp-More-Stereo-Dimensional-Array(SDA)

Jim

drgalexo

Thanks again for the welcomes and the great information. I'm from just south of Buffalo, NY and I appreciate all the help. I have run some of the simple tests and have found that when I shift the balance control to the right side only, there is no sound out of the left speaker at all, and when to the left side there is sound out of the right speaker, but it is distorted. Apparently I have problems with both speakers right now. The guys at the shop where I bought the Denon monoblocks have convinced me to attempt to remove the speakers myself and switch the appropriate units in the opposite speaker to see what is working. Great references Jimbo and others, a lot of this stuff is over my head right now but I have never let that stop me before. I also need to contact Denon to see if they can be a common ground but I do have the blade-blade interconnect so I need to see if that will even work evhudsons stated. Gary

vcwatkins

drgalexo wrote: »

Well I guess I'm just going to have to get that interconnect cable working after all. Thanks for all the great info and resources.

You'll be sooooo glad once you've got it figured out. Amazing speakers, magical sound.
Welcome to the best forum around.

Craig

drgalexo

Hey GlennDog, I notice you use an Adcom GFA 5802. The store I bought my Denon POA 6600 monoblocks from have the same Adcom amp. I am thinking of exchanging the amps but I see the Adcom GFA 5802 is also a non common ground amp. Do you have a blade-blade interconnect or a blade-pin connection.

squeeb

I have an Adcom 5503. I needed to "strap" the negatives of the left and right channels so resolve the problem. To strap you just run a piece of speaker wire from one negative terminal to the other. Problem solved. I have a blade/blade SDA/SRS2. Disclaimer - you may want to contact Adcom directly to make sure it won't harm the amp or if someone who has done it with the 5802 can chime in on CP.

GlennDog

squeeb wrote: »

I have an Adcom 5503. I needed to "strap" the negatives of the left and right channels so resolve the problem. To strap you just run a piece of speaker wire from one negative terminal to the other. Problem solved. I have a blade/blade SDA/SRS2. Disclaimer - you may want to contact Adcom directly to make sure it won't harm the amp or if someone who has done it with the 5802 can chime in on CP.

drgalexo, do the above and that will tide you over until you can invest in the Dreadnaught . . .

I've got the P/B combo . . . Consider the 5802, it packs a punch and you will be satisfied . . . until you get the itch!!!! (and that will be a long time down the road)

G

drgalexo

The Polk Manual for the SDA SRS and the Addendum Manual are very specific about only the later version of the SRS2 can be used with the AI-1 interconnect (ie. the pin/blade) type. I have the blade/blade 1986 version of the SRS2 which evhudsons also indicates may not be used with the monoblocks and nicely avoided with the Parasound amp. My question is can the Denon POA 6600 monoblocks be used with my speakers blade/blade if I build a DarqueKnight type Dreadnaught and still use the same blade/blade connect? It seems like just connecting the negatives or the frames of the amps should do it but this is not suggested. I prefer to keep the monoblocks at this time if possible.

Toolfan66

Forget using the dreadnought you can't use it. Not sure if you can strap your monos but I do know you can strap the Adcom 5802..

Polkie2009

Congrats on the SDA SRS 2 speakers drgalaxo! I've had mine since 1987 or 88, bought them new.Mine did_ have the pin-blade interconnect. A couple of years ago, I was in the same boat as you are now, looking into the possibility of going with an AI-1. The guys are right, I believe with those earlier issued SDA SRS 2 speakers that have the pin-pin interconnect, you can't_ use the AI-1, due to the speaker's circuitry I suppose. In fact , I had to make sure my speakers serial numbers were in the right catagory(even though they were pin-blade) to be illigible to use an AI-1. Maybe others will chime in too with more info. Good luck with the speakers they are awesome!

drumminman

I think TF and EVH are correct, you can not use the AI-1 (dreadnought) with those SDA's. Your only option is to strap the negatives if the manufacturer OK's it.

drgalexo

I thought for sure I saw DarqueKnight build a dreadnaught for a blade/blade interconnect but I can't find the link and I can't remember what series it was for. Shurkey explains how it works and I just don't understand why the only odd ball is the SDA SRS 2 blade/blade. Still waiting to hear from Denon about wiring the two monoblocks together but looking more like I will need to go with an integrated amp. Really confussing why these speakers are so different but I am finally ready to take them apart and see why they aren't working completely. Ofcourse this project could kill the speakers all together and then I could look for non SDA's and keep the monoblocks.

drgalexo

I just realized that Squeeb has the same SDA SRS 2 blade/blade, and uses monoblocks should be the same even if different amps.?

drumminman

drgalexo wrote: »

I just realized that Squeeb has the same SDA SRS 2 blade/blade, and uses monoblocks should be the same even if different amps.?

Patience my friend.

Have you contacted Denon about strapping the negatives? My best advice is to do so. Email them a copy of the schematics so they can see what you're dealing with and give you feedback/advice.

Did a quick google search and came up with these guys. Not Denon, but may be able to help: http://www.vicol-audio.ro/Denon_POA-6600.php

Apparently, those are a Nelson Pass design and are highly thought of by some. Probably worth going to a little trouble.

drgalexo

Good advice drummin, patience is the hard part. Nice link to the Denons, I think they will be great if I can use them. I have contacted Denon and I am waiting for a reply from them and also Polk.

drgalexo

I have removed three bad drivers from the speakers. The two dimensional MW 6509 in the left channel and the bass dimensional (bottom) in the right channel were all blown. Are the MW 6503 the same as my speakers are labelled with the number crossed off and 6509 hand written. I need to get three of these and I want to make sure I get the right replacements.

drgalexo

Denon advises to not connect negatives and the amplifiers are not common ground. Looks like I will have to go the integrated amp route.

drumminman

It's better to know. There are lots of good choices out there for integrateds, or you could get a common ground stereo power amp.

I ran an Odyssey Stereo Stratos Plus for a year without issues of any kind. Sounded really good, but I wanted more power. So I sent it back to Klaus and had him convert it to dual mono.

He basically gutted it and put all new higher quality parts in. Now that it's dual mono I'm required to use the AI-1 interface, whereas before I used it cause it sounded so good

drgalexo

The Odyssey Stratos looks great Drummin. I actually meant a separate amplifier not integrated. I might keep the Denon monoblocks anyway, I really like them, but there are a lot of good choices out there. Can't wait to get the speakers fixed.