New Polk SDA 1C owner

aldine, the Monitor 10As are the best of the Monitor 10s as they have the Peerless tweeter so, if they are in nice condition, I think that is a fair price and they are well worth it. I would highly recommed your getting the Monitor 10As. I have two pair and love them. I also own the Monitor 7Bs. I bought my 7Bs locally for $120 last year so $140 for the Monitor 7Bs is a little on the high end but perhaps you can talk the seller down a bit. The Monitor 7Bs should also have the Peerless tweeter (mine do). If you can afford it and can talk Seller(s) down a little, you may want to get both the 10As and 7Bs. Both are great speakers. As noted, the Monitor 7s have better imaging and the Monitor 10s have better bass. Some people prefer the Monitor 7s although personally I prefer the Monitor 10As overall. It is just a matter of taste and preference. Both are fantastic speakers and worth picking up.

Quote:

---

Originally Posted by aldine

I have been tearing my hair out because when I tried to check the dimensional drivers per the SDA handbook the left side was not working properly. The dimensional sound and the regular sound was both coming out of the 6511 speakers. The 6510 ones were silent. The right side seemed to be working properly. I rechecked the wiring in all of the speakers, but I can not figure it out. Any ideas would greatly be appreciated.

---

aldine, is the left speaker the one you made the new harness for?

No, it was the right one.

Quote:

---

Originally Posted by aldine

No, it was the right one.

---

then I would take TennMans suggestion, and start from scratch. Be sure the IC cable is disconnected, you might want to pull the tweeter connector off too, just as a precaution.

With just the positive and the ic leads hooked up there is no sound when I unhook one of the black leads from the big coil to the crossover board on the left side. When I unhook one of the black leads from the big coil on the right side there is still sound.

Quote:

---

Originally Posted by aldine

With just the positive and the ic leads hooked up there is no sound when I unhook one of the black leads from the big coil to the crossover board on the left side. When I unhook one of the black leads from the big coil on the right side there is still sound.

---

aldine, you have to disconnect from the amp and IC cable, and do the battery/phase check. you gotta start from scratch

Quote:

---

Originally Posted by F1nut

Not only do the parts fit better on Tony's boards, the boards are thicker and the traces are heavier. Using them is a no-brainer.

---

I thought those round crossovers had thick traces but while I'm on the subject I hate my boards.

I did the battery/phase test and when I did the left speakers only the stereo drivers moved. When I did the right side all four moved. I swapped the crossover boards, then got the reverse. Only the two stereo drivers on the right side moved. Do I have a bad crossover board?

Quote:

---

Originally Posted by aldine

I did the battery/phase test and when I did the left speakers only the stereo drivers moved. When I did the right side all four moved. I swapped the crossover boards, then got the reverse. Only the two stereo drivers on the right side moved. Do I have a bad crossover board?

---

aldine, unless the board received physical or over-current damage to it, I doubt it's the board itself that's bad. Check all the components on the board for bad/loose solder joints, or evidence of overheating. Also check all the molex connectors for loose solder joints or bad internal prongs. Check the wiring to the large Inductor (the two black wires coming off the board), and make sure the spade connectors are good, and the inductor wires to the back of the little terminal strip are good. The board itself can be easily removed from the inductor base. The nylon standoffs snap in to the large inductor. Just take a pair of needle nose pliers, and crimp the part that goes through the black plastic inductor base. The should release easily.

I really appreciate all of the help westmassguy. You must be an early bird like I am. When I got the speakers they were in pieces including the boards so they were already off of the inductor base. Hooking up the battery was a stretch for my skills with speakers, but I am learning. I would think that something on the board is bad because when I switched them they behaved the same in both speakers. Which way should it be, all four drivers moving or just two? I have ordered new caps and resisters. Maybe when I install them it will be fixed. Unfortunately I have to go to work now. ( I know, where are my priorities.)

With the external speaker/amp wires removed, the IC cable removed, and all internal harnesses connected, attach the jumper wire to the external speaker terminals/binding posts, and BRIEFLY touch the wires to a battery. All four woofers should move, and move in the same direction.

One other thing, double check that the driver and tweeter harnesses are connected to the proper connector on the board. The connectors are identical, they're inverted on the board, but could be inserted into the wrong connector.

Here are some pictures of the board that is suspect. Does anyone see anything obviously wrong with it?
Attachment 81228Attachment 81229

aldine, while my SDA's are not 1C's (my previous pair were) I recently finished a pair of SDA CRS+'s, with just about every mod that we know of around here. I put a thread together documenting what I did, if you want to have a look, here is the link:

http://www.polkaudio.com/forums/show...s-are-complete!

Quote:

---

Originally Posted by aldine

Here are some pictures of the board that is suspect. Does anyone see anything obviously wrong with it?
Attachment 81228Attachment 81229

---

aldine, I don't see anything obvious from the photos. Did you do the battery test exactly as I said?

Yes I did. It has to be something with that board because with the battery test only the stereo speakers moved when it was installed in both speakers. All four speakers moved on both sides with the other board in it.

Attachment 81233

Quote:

---

Originally Posted by aldine

Yes I did. It has to be something with that board because with the battery test only the stereo speakers moved when it was installed in both speakers. All four speakers moved on both sides with the other board in it.

---

This is the dimensional section of the board. Check to make sure you have continuity at connectors 1 & 2, the 1.25 mh inductor, and the large 16 mh inductor. An open circuit at any of those points will prevent signal going to any of the dimensional woofers.

Take a closer look at solder connection with the arrow pointing at it. It's hard to tell anything much from a photo but it looks suspect to me. Check the lead going into it on the other side of the board as well.

Attachment 81234

Quote:

---

Originally Posted by TennMan

Take a closer look at solder connection with the arrow pointing at it. It's hard to tell anything much from a photo but it looks suspect to me. Check the lead going into it on the other side of the board as well.

Attachment 81234

---

Yeah it does, and I believe that's the 1.25 mh inductor I believe

Quote:

---

Originally Posted by TennMan

Take a closer look at solder connection with the arrow pointing at it. It's hard to tell anything much from a photo but it looks suspect to me. Check the lead going into it on the other side of the board as well.

Attachment 81234

---

I would agree with this completely. That solder joint looks to be a cold joint where solder did not stick to component lead very well. It's probably hard to check from the component side as it looks like it's one of the leads from the 1.25mh inductor which is very close in to the 2.5mh inductor you may need to cut the cable tie holding it to the board. i would solder that joint very well and check it first. I would be willing to bet it solves your problems. Good luck.

I almost forgot to mention you may need to check the inductor lead to be sure the insulating coating is cleaned back from this area good to be sure the solder can stick to the copper good. I only mention this because the boards have all stock components and don't appear to have been tampered with so there's no reason this one joint should have been touched either. This would mean that either it was just a bad joint that became looser over time or it was a good joint with not much to stick to in the first place.

Quote:

---

Originally Posted by Mr. Bubbles

I would agree with this completely. That solder joint looks to be a cold joint where solder did not stick to component lead very well. It's probably hard to check from the component side as it looks like it's one of the leads from the 1.25mh inductor which is very close in to the 2.5mh inductor you may need to cut the cable tie holding it to the board. i would solder that joint very well and check it first. I would be willing to bet it solves your problems. Good luck.

I almost forgot to mention you may need to check the inductor lead to be sure the insulating coating is cleaned back from this area good to be sure the solder can stick to the copper good. I only mention this because the boards have all stock components and don't appear to have been tampered with so there's no reason this one joint should have been touched either. This would mean that either it was just a bad joint that became looser over time or it was a good joint with not much to stick to in the first place.

---

Agreed. From what the OP says these were in pieces, so, they could have been roughed up.
Might not be a bad idea to re-flow all the joints in the dimesional section of the board.

You guys are amazing. That was it. The inductor lead had broken off. I soldered it back on, did the battery test and all four woofers moved. I did not have a lot of wire on the inductor lead to work with so I am not sure if it will hold up. Thank you very much for your help. I am now listening to my "new" SDA speakers the way they are supposed to sound for the first time.

Quote:

---

Originally Posted by aldine

You guys are amazing. That was it. The inductor lead had broken off. I soldered it back on, did the battery test and all four woofers moved. I did not have a lot of wire on the inductor lead to work with so I am not sure if it will hold up. Thank you very much for your help. I am now listening to my "new" SDA speakers the way they are supposed to sound for the first time.

---

Awesome, now go Enjoy them till your new parts come in :)

Yes be sure that they are labeled before you unplug them when you do any work as westmassguy said they will plug into either one.

Quote:

---

Originally Posted by westmassguy

One other thing, double check that the driver and tweeter harnesses are connected to the proper connector on the board. The connectors are identical, they're inverted on the board, but could be inserted into the wrong connector.

---

congrats. Enjoy.

I'm glad to hear that little white arrow was helpful to you. Enjoy your speakers! Let us know what you hear when you get the new parts in the crossovers.

I have upgraded the crossovers just as westmassguy did. I am listing to music I have been playing for 40 years and hearing overtones and subtleties I have never heard before. I am very pleased. Saturday the new tweeters are supposed to arrive. How long will it take for all of these components to break in? Also how much batting material should be in the speakers? Do I need to seal anything up?
Thanks for all of the help.

Quote:

---

Originally Posted by aldine

I have upgraded the crossovers just as westmassguy did. I am listing to music I have been playing for 40 years and hearing overtones and subtleties I have never heard before. I am very pleased. Saturday the new tweeters are supposed to arrive. How long will it take for all of these components to break in? Also how much batting material should be in the speakers? Do I need to seal anything up?
Thanks for all of the help.

---

Break-in on the caps minimum 150-200 hours. Tweeters 50 hours or more.
The Dacron batting should be tucked and tacked in place if neccesary, in the top section only. The bottom portion of the cabinet behind the PR should be clear of any batting.
Check all the internal seams. I usually run a bead of clear acrylic caulk around the interior seams, smoothed out with my finger tip, just to make sure everything is sealed tight. Make sure all your gaskets are good. Think about installing hurricane nuts and machine screws, Dynamatting the drivers and prs, and don't forget to glue the magnet assemblies while you have everything out of the cabinet.

Thanks for the reply westmassguy. Since I bought these speakers in pieces I am not sure what parts are supposed to be there. I have gaskets for the tweeters, but not for any of the other speakers. What do you mean by "glue the magnet assemblies"?

Quote:

---

Originally Posted by aldine

Thanks for the reply westmassguy. Since I bought these speakers in pieces I am not sure what parts are supposed to be there. I have gaskets for the tweeters, but not for any of the other speakers. What do you mean by "glue the magnet assemblies"?

---

Most on here use Armaflex Insulating Tape to make new gaskets for the Woofers and Passive Radiators. It comes in a roll, 2" wide X 1/8" thick. Cut it in strips about 1/2" wide, and apply it to the back of the flange on the woofers and PRs to seal them to the cabinet.
The magnets on vintage Polk woofers have a habit of shifting if they are dropped, or if the speaker itself is handled roughly. The glue that was originally used, deteriorated. I attached a photo showing a Polk driver that has had the magnet epoxied in place, and has been Dynamatted. The epoxy is applied to the joint where the back plate and magnet meet.
Attachment 81482