Repairing a 6503 with magnet issues?? from a CRS

gjposner

I just bought a pair of CRS's for a total of $16.72. I checked the drivers moving on one and the condition of the other and just loaded them up at that price.. I never bothered to see that one of the 6503's (not a doped one) was seized.

Upon opening the cabinet I was amazed at the BIG **** INDUCTORS! As a Tesla Coil guy, I was impressed, but as an audio guy I immediately noticed that the magnet had come unglued and pinched the VC. I was able to remove the magnet and the VC is in great shape, so I think it can be salvaged, however I am not sure how to get everything back in place. Is there a set of instructions on how to do this? What about gluing the others in place? What is most commonly used?

I do 3D Printing for a living (small business owner!), so I can literally make whatever I need, and I work with tons of different super glue's so if CA will work. I have everything from no odor up to water proof in varying CPS levels. I just want to make these babies work again!

Alternatively, I would like to see about just replacing them if the repair is not possible/practical.

Also, dual blade interconnect cable. Need to either make one, or get the ends. I do not mind making something from scratch, I just want to know if the top spade on one goes to the top spade on the other. I saw the nice pretty list of upgrades, but all the links are broken as there are plenty of upgrades I want to do to these, but I cant see anything

Any help is greatly appreciated!

F1nut

I never bothered to see that one of the 6503's (not a doped one) was seized.

They only came doped.

Is there a set of instructions on how to do this?

There are a few threads on how to do that, but good luck finding them. Perhaps one of the guys that has done that work will chime in.

What about gluing the others in place? What is most commonly used?

Either run beads of JB Weld or Loctite Power Grab around the magnets.

Also, dual blade interconnect cable.

Polk sells the cable, runs about $45.00.

gjposner

On the set I have, in each cabinet there is one doped and one standard paper cone.. They are marked with correct date codes too..

I have powergrab so I will go with that!

For $45 I would rather build it myself.. I cant imagine it is that hard. I just need to know polarity and then I am off to the races. It also seems I can just replace it with a female XLR jack, but the thread on it is gone.

Unfortunately 90% of the threads on how to fix/mod the SDAs are dead

F1nut

The Neutrik SpeakOn connectors are a better choice if not using the original. Schematics are posted at the top of the page.

F1nut

Forgot about this.....

On the set I have, in each cabinet there is one doped and one standard paper cone.. They are marked with correct date codes too..

Very odd.

gjposner

F1nut wrote: »

Very odd.

Potentially a recone because the surround does not say Polk on it and the dustcap is rigid vs the soft flexible one on the other driver. A recone seems most likely if they are both suppose to be doped on both speakers.. I wonder how it will change the sound (I doubt it would matter anyways, never heard these before ha ha)

F1nut

Ah yes, that makes sense. If the plain drivers are in the dimensional position you may not notice the difference, still I would get the proper ones.

gjposner

F1nut wrote: »

Ah yes, that makes sense. If the plain drivers are in the dimensional position you may not notice the difference, still I would get the proper ones.

I looked up the price of new drivers, because I cannot find factory recone kits, it is not worth the money to me at the moment. I would rather get them playing then worry about upgrades like that.

I did the power grab and it seems to work well, now I just have to figure out how to re-seat the coil and magnet without damaging anything..

westmassguy

There is no re-cone kit for the Polk MW65-- Series that I'm aware of, so whoever did it, made up the kit. The Rubber Surrounds most likely are very thick compared to the originals.
You'll have to remove the dust cap, and shim the voice coil former, while positioning the magnet and back plate. Good luck with that.

F1nut

Westmassguy is right, there are no re-cone kits for Polk drivers. However, Polk sells new ones. Also, check eBay for used ones.

westmassguy

F1nut wrote: »

Westmassguy is right, there are no re-cone kits for Polk drivers. However, Polk sells new ones. Also, check eBay for used ones.

Hey Jesse, Happy Thanksgiving !

F1nut

Happy Thanksgiving, David.

Schurkey

gjposner wrote: »

I think it can be salvaged, however I am not sure how to get everything back in place. Is there a set of instructions on how to do this?

F1nut wrote: »

There are a few threads on how to do that, but good luck finding them. Perhaps one of the guys that has done that work will chime in.

http://forum.polkaudio.com/discussion/135716/lets-try-to-fix-a-mw6511-damaged-in-shipping/p3 (Near the bottom of the page.)

gjposner

westmassguy wrote: »

There is no re-cone kit for the Polk MW65-- Series that I'm aware of, so whoever did it, made up the kit. The Rubber Surrounds most likely are very thick compared to the originals.
You'll have to remove the dust cap, and shim the voice coil former, while positioning the magnet and back plate. Good luck with that.

Huh, its a good recons kit then! The other works well, seems to have good movement and reads proper. It seems maybe they only replaced soft parts, like a damaged cone and left the original VC intact? Not sure what to look for honestly. These are my first pair of Polks.

I really have no faith in shimming it myself, that magnet is a **** to move.. Any ideas other than just replace it? Speaker exchange sells the drivers, but man they are pricey

westmassguy

MW6503s turn up on eBay. You can buy new replacements directly from Polk for $48.00 each with free shipping: 1-800-377-POLK (7655) Option 1

F1nut

Schurkey wrote: »

THANKS, BRUNO!

He's gone.

Schurkey

F1nut wrote: »

Schurkey wrote: »

THANKS, BRUNO!

He's gone.

I'd have sent this via PM, but I can't figure out how.

Bruno's gone? When did that happen? Who's fixing issues with the forums now?

F1nut

Yep. Recently. No one, just like before.

gimpod

westmassguy wrote: »

MW6503s turn up on eBay. You can buy new replacements directly from Polk for $48.00 each with free shipping: 1-800-377-POLK (7655) Option 1

^ This is really the only way to go or keep looking for one on e-bay they come up a lot from time to time. Let me tell you having done this repair it's just not worth the head ace trying to get everything centered without **** up the VC easier to spend the $48.00 and get a new one.

Schurkey wrote: »

Who's fixing issues with the forums now?

Apparently no one !, I got this halfway through making a post a while ago.



Nice forum software and servers. - NOT

gjposner

gimpod wrote: »

westmassguy wrote: »

MW6503s turn up on eBay. You can buy new replacements directly from Polk for $48.00 each with free shipping: 1-800-377-POLK (7655) Option 1

^ This is really the only way to go or keep looking for one on e-bay they come up a lot from time to time. Let me tell you having done this repair it's just not worth the head ace trying to get everything centered without **** up the VC easier to spend the $48.00 and get a new one.

Schurkey wrote: »

Who's fixing issues with the forums now?

Apparently no one !, I got this halfway through making a post a while ago.



Nice forum software and servers. - NOT

Oh wow.. That is not too easy.. Guess I will watch ebay lol..

Mine broke at the magnet, so I have the magnet and pole piece separated from the rest of the speaker.. I can make a jig and try though, but I will be using a low strength glue and then just loctite on the outside to really seal it up.

Are these really worth spending 100 on to get fixed though? And do I need the exact 6503 drivers?

Also any idea about the possible recone I have?

Schurkey

gjposner wrote: »

Oh wow.. That is not too easy.. Guess I will watch ebay lol..

Mine broke at the magnet, so I have the magnet and pole piece separated from the rest of the speaker.. I can make a jig and try though, but I will be using a low strength glue and then just loctite on the outside to really seal it up.

Repairing the magnet/pole piece on my 6509 wasn't that hard for me. In fact, I thought it was outright easy. Different strokes for different folks. Use a proper anaerobic adhesive.

gjposner wrote: »

Are these really worth spending 100 on to get fixed though? And do I need the exact 6503 drivers?

"These" speaker systems? Absolutely. Yes, you need 6503 drivers.

gimpod

Polk never made recone kits for these drivers and at $48.00 for a new one it just doesn't make sense to do so.

All the recone jobs on Polk drivers are made from different speaker recone kits and hacked together to kinda work. IMHO they look and sound like dog **** (Are you kidding me P.O.O.P. is cencered. This is just to P.C.), not worth the money unless you want an expensive door stop.

Are they worth spending $100 on fixing them, that's up to you but given what you paid for them I'd say yes.

And yes if the broken drivers are MW-6503's replace them with MW-6503's

gjposner

Schurkey wrote: »

gjposner wrote: »

Oh wow.. That is not too easy.. Guess I will watch ebay lol..

Mine broke at the magnet, so I have the magnet and pole piece separated from the rest of the speaker.. I can make a jig and try though, but I will be using a low strength glue and then just loctite on the outside to really seal it up.

Repairing the magnet/pole piece on my 6509 wasn't that hard for me. In fact, I thought it was outright easy. Different strokes for different folks. Use a proper anaerobic adhesive.

gjposner wrote: »

Are these really worth spending 100 on to get fixed though? And do I need the exact 6503 drivers?

"These" speaker systems? Absolutely. Yes, you need 6503 drivers.

Did you use the method showed in the post? Or something different? My issue becomes, unlike the poster in that, my magnet is not attached so I cannot use it as a point of reference, I would have to build something wide enough to fit the magnet with a lip for the lower section to be centered as well. Seems challenging, may need to 3D print something for this..

If I can get new drivers for cheap I will replace them, otherwise I will use these as they are. I have never heard these before, so it is going to sound good no matter what. I am sure I have heard better, but I would like to keep my investment for value low (I will be building stands at some point too!)

gjposner

gimpod wrote: »

Polk never made recone kits for these drivers and at $48.00 for a new one it just doesn't make sense to do so.

All the recone jobs on Polk drivers are made from different speaker recone kits and hacked together to kinda work. IMHO they look and sound like dog ****, not worth the money unless you want an expensive door stop.

Are they worth spending $100 on fixing them, that's up to you but given what you paid for them I'd say yes.

And yes if the broken drivers are MW-6503's replace them with MW-6503's

It is just odd to me then that the cones are almost identical in their design, it is simply the dust cap that is different, the cone itself is the same shape, just not doped.

I have Spica TC-50's so I understand the reasoning behind the doping, but not having any income at the moment (I own a small business that is still working on paying off a big machine) it is hard to justify $100. I will watch ebay though and see what I can do and hopefully I can get used ones for a good price.

Now I just have to make the interconnect cable, debating to try and replicate it or just remove it for an RCA or XLR jack instead

gimpod

If you insist on fixing them here's some links that show whats involved, good luck.

Resetting a loose magnet (with pictures)

As promised Pics of the magnet Jig

Just make sure when it's all together that the VC is not grounded out to the driver basket.

gjposner

gimpod wrote: »

If you insist on fixing them here's some links that show whats involved, good luck.

Resetting a loose magnet (with pictures)

As promised Pics of the magnet Jig

Just make sure when it's all together that the VC is not grounded out to the driver basket.

Should have thought to post to AK as well! Thanks! At this point I have nothing to lose but time when trying this! will report results. I will also be eyeing ebay for a good set of 6503's!

leftwinger57

I had a 6503 go bad on my 2Bs and I got one off E-Bay for $19 at a BIN price. It did come doped as you were told all mid woofers are doped and yours is a repro of some kind. Replace yours w/ original either from auction or Polk. As for the blade /blade i/c I was told large blade carries the signal and the small is just for support. Neutrik Speak-On connectors w/ a decent speaker cable works very well and is very inexpensive just watch your jumpers and flying lead. I think I paid more for shipping than the actual parts.
Good luck..... and HAPPY THANKSGIVING TO ALL

gimpod

leftwinger57 wrote: »

As for the blade /blade i/c I was told large blade carries the signal and the small is just for support.

That only applies to the early 1987 SDA 1C (Dual board crossover) and SDA 2B, Also in this case it's the small blade that carries the signal. Look at the schematic for the SDA 2B 1987 bb.pdf

westmassguy

Have we determined exactly which model CRS the OP has? MW6503s were used in several models. Some photos would help. Do they have two tweeters? If so, they're the original 1984 CRS, and both conductors in the Interconnect cable carry signal. I would also highly recommend the SpeakON Plugs and Sockets for the new interconnect. They're inexpensive and bullet-proof.

gjposner

leftwinger57 wrote: »

I had a 6503 go bad on my 2Bs and I got one off E-Bay for $19 at a BIN price. It did come doped as you were told all mid woofers are doped and yours is a repro of some kind. Replace yours w/ original either from auction or Polk. As for the blade /blade i/c I was told large blade carries the signal and the small is just for support. Neutrik Speak-On connectors w/ a decent speaker cable works very well and is very inexpensive just watch your jumpers and flying lead. I think I paid more for shipping than the actual parts.
Good luck..... and HAPPY THANKSGIVING TO ALL

I'll keep an eye on eBay! Thanks for the tip!

gjposner

westmassguy wrote: »

Have we determined exactly which model CRS the OP has? MW6503s were used in several models. Some photos would help. Do they have two tweeters? If so, they're the original 1984 CRS, and both conductors in the Interconnect cable carry signal. I would also highly recommend the SpeakON Plugs and Sockets for the new interconnect. They're inexpensive and bullet-proof.

I have the dual tweeter model. I'll look into what would be required for speakon. Kind of hesitant to make holes different but it seems the former owner had no issue re coning potentially 2 drivers.

I attached some photos, not sure if it will work from my phone though.. The speaker says 3121 I think? I'm not near them currently.