Welcome Home SDA-1C's

Saftgeek

The deal is done... :cheesygrin:
I picked up the speakers this morning. I paid $400 and I couldn't be happier. These speakers are pristine. There isn't a mark on the cabinets, the grill cloth, the drivers, tweeters... They literally look like they could be brand new.

I had planned to take a battery with me this morning so I could fuzz the speaker inputs and make sure the drivers moved... I forgot it this morning. When I got home I did check them... Much to my dismay one of the drivers in the right speaker wasn't moving. I thought about magnet shift but couldn't see how that happened since we were so careful. Anyway, I took the driver out of the cabinet, disconnected the wires from the crossover, and it worked fine. I went ahead and put the driver back in and removed the passive radiator, wiggled the wiring harness a little, and once again fuzzed the speaker. This time the driver moved, but not to the degree the others did. I stopped there, since I plan to upgrade the crossovers and tweeters before I listen to them. I figured something in the crossover was limiting the signal... Not sure if I'm right/wrong, but for now I'm going to go ahead and see what happens.

It looks like these are pin/blade. I have all the original paperwork, cables, etc... that came with them. The previous owner got a heck of a deal when he bought them new... he paid a little over $900 for them in 1990.

Now I need to see about ordering the tweeters and start studying on how to de-solder and re-build the crossovers. Looks like phone calls early next week. Can anyone tell me if the old tweeters are worth anything? Can I sell them on ebay or on here? That would help offset the cost of new.

Thanks again everyone... I am one very happy camper!

-Saftgeek

gwg_97

Score! Tweeters usually go for about $25 on eBay. Speaking from recent experience, soldering is pretty easy. Dive in!

gdb

Some of the drivers are fed by the I/C cable, when it's in place, IIRC.

Polkersince85

^^^ +1

The driver is probably OK. That's how SDAs are designed. Hook em up with the I/C and you will be good to go.

gdb

While you have em apart.....I'd recommend doing the JB Weld. Link below is to one of the better threads on the subject. Do not listen to those who claim the glue is not a problem, for whatever reason......they're lying to you.

http://www.polkaudio.com/forums/showthread.php?98202-JB-Welding-your-magnets-on-your-old-drivers

PolkieMan

Good deal, it's hard to find older speakers that are still perfect.
So your not going to listen to them a while to kinda to establish some sort of baseline to compare to?
If you don't have the interconnect cable one can be made easily.
Do you know about www.gimpod.com?

Saftgeek

I do have the interconnect cable. I don't want to listen to them because my home theater system is supposedly not a common ground. I haven't had time to check with a multi-meter yet. I'm hoping I will have time tomorrow. From what I understand i need to check continuity between the two main speaker negative leads.
FWIW - I do plan to JB Weld the speakers. That is pretty simple. I just want to Dyna-mat them at the same time.

-Saftgeek

gimpod

PolkieMan Thanks for the plug. :biggrin:

gdb wrote: »

Some of the drivers are fed by the I/C cable, when it's in place, IIRC.

Polkersince85 wrote: »

^^^ +1

The driver is probably OK. That's how SDAs are designed. Hook em up with the I/C and you will be good to go.

Yes and no, I suggest you read the paper by Mathew Polk and Stu Lumsden Inductor Upgrades For SDA.pdf paying close attention to the first couple paragraphs. Where Mathew Polk explains the function of the big inductor (Everyone around here refers to it as the SDA inductor) that's connected to the dimensional drivers and the speakers ground allow them to function as sub-bass drivers in the 50hz - 150hz range.

gdb wrote: »

While you have em apart.....I'd recommend doing the JB Weld. Link below is to one of the better threads on the subject. Do not listen to those who claim the glue is not a problem, for whatever reason......they're lying to you.

http://www.polkaudio.com/forums/showthread.php?98202-JB-Welding-your-magnets-on-your-old-drivers

I agree it cheap insurance and a lot easier than trying to get a good original driver, Took over 6 months and some horse trading to get one for my 1C's. I don't think those who say there's no need for it are lying, they've just haven't run into a problem with it yet.

This is just my option, If I were you just JB Weld all the drivers, check and clean all the connections at both ends of the wiring, put them pack together and get use to them in there stock form before making any changes that way you'll have a good base line to start with. Also this will give you time to start saving money for the upgrades & mods you'll need it. :cheesygrin:

BTW: Welcome to Club Polk and the rabbet hole. !!

F1nut

Over 60 MWxxxx drivers in and out of here, never had a problem. I'm not saying that it couldn't be a problem, but it's not the problem a certain putz makes it out to be.

I don't want to listen to them because my home theater system is supposedly not a common ground.

What do you have?

Saftgeek

I took the multi-meter to the Onkyo TS-DX898 speaker negative terminals and they were a dead short. I went ahead and gave them a listen. There is definitely trouble in paradise. One of the drivers on the right side is not working. I took it out and swapped with the one next over, it didn't work there either. I then took it out completely and used a battery to see if it was free moving... it did move, but not to the extent of the other ones. When I connected it back to the speaker wires and tried the battery all of them moved, but not nearly as much as when the suspect speaker was not attached.

Right now I'm scratching my head. I'm fairly certain the crossover is good because when I swapped positions the other driver worked fine. I could be wrong... but I think I may have a wounded soldier. Looking closely at the magnet on the suspect speaker there is definitely a small piece of the magnet missing. Not a lot, and nothing to indicate the speaker had ever been removed. I'm thinking this may be damage from the factory and it really wasn't bad enough to matter.

At any rate, I am looking for some idea of what to do to verify if my trouble is the driver or not. I used to do a lot of car stereo installs and troubleshooting back in the day, so I'm not totally without any kind of skill... I'm just not familiar enough with degraded components and what they can do to affect the sound of an SDA. Any and all help would be much appreciated.

-Saftgeek

gdb

Oh yeah....... that's that nonexistent problem the other putz was spoutin' off about. Sorry to hear that you've got some slipped drivers. They can be salvaged if you're at all "handy".

Link to repair info link.......
http://www.polkaudio.com/forums/showthread.php?79649-DIY-magnet-re-centering-info&highlight=repair+magnet

mesquitehead

Those are the "studio" versions, I have a pair just like them. COngrats on a fine purchase!

Oldfatdogs

Congratulations on your score.You will figure out the problems lots of information here.

gudnoyez

Congratulations on being a new and happy SDA owner. I had a pair hooked up to a Yamaha AVR for a while, a tech at Yamaha told me that all of thier AVRs and recievers are common ground, after hooking them up to a integrated Technics the difference was most noticable, and will soon be getting some seperates for them. I was grinning from ear to ear after listening to Time from Floyd and hearing alarm clocks going off all around me after hooking them up for the first time. Nice score enjoy them.

gimpod

Saftgeek wrote: »

I took the multi-meter to the Onkyo TS-DX898 speaker negative terminals and they were a dead short. I went ahead and gave them a listen. There is definitely trouble in paradise. One of the drivers on the right side is not working. I took it out and swapped with the one next over, it didn't work there either. I then took it out completely and used a battery to see if it was free moving... it did move, but not to the extent of the other ones. When I connected it back to the speaker wires and tried the battery all of them moved, but not nearly as much as when the suspect speaker was not attached.

Right now I'm scratching my head. I'm fairly certain the crossover is good because when I swapped positions the other driver worked fine. I could be wrong... but I think I may have a wounded soldier. Looking closely at the magnet on the suspect speaker there is definitely a small piece of the magnet missing. Not a lot, and nothing to indicate the speaker had ever been removed. I'm thinking this may be damage from the factory and it really wasn't bad enough to matter.

At any rate, I am looking for some idea of what to do to verify if my trouble is the driver or not. I used to do a lot of car stereo installs and troubleshooting back in the day, so I'm not totally without any kind of skill... I'm just not familiar enough with degraded components and what they can do to affect the sound of an SDA. Any and all help would be much appreciated.

-Saftgeek

Sounds like a bad driver (voice coil shorting out or fried), What driver is it the MW6510 or the MW6511. Take your meter and measure the DCR MW6510 = 6.57 Ohms and MW6511 = 3.13 Ohms. Also check for any reading between the connector and basket/base plate (this is a no no). Ether way I would be on the lookout for a replacement. FYI the MW6511's are the stereo drivers and the MW6510's are the dimensional drivers.

A word on magnet shift: This is almost always caused by really rough handling or bad packing and ends up with one of two results, 1. The magnet shifts jamming the voice coil against the base plate i.e frozen driver, 2. The magnet comes completely off. In both cases usually the driver is toast because the voice coil gets damaged. If the voice coil is ok the driver might be able to be fixed but I still wouldn't trust it and would be looking for a replacement. Now Polk still sells a replacement driver but it does not look exactly like the original and some say they don't sound the same while others say they sound the same. (how's that for confusing issue)

F1nut

gdb wrote: »

Sorry to hear that you've got some slipped drivers.

Nothing like jumping to conclusions. You don't know that the magnet has shifted from what he has said so far and of course, you didn't bother to ask him for more information. I know...hell, we all know you don't realize it, but there are other possible causes for his problem.

So, why don't you ask for more information? Do you even know what to ask?

BTW, other than the known dead drivers you purchased to experiment on, exactly how many good ones that you have owned had the magnet shift while in use? While in transit?

Saftgeek

Awwwwww... I am really bummed out now. I pulled the driver and it is toast. A complete short. It looks like I've got an extra passive radiator in my right speaker. I am in the market for a MW6511. I would love two, just in case. I've looked on ebay, Craigslist and did a random Google search... it looks like I'm in for a real easter egg hunt now. It's such a shame too, because these speakers are really, really nice.

I guess I now have a new purpose to my life... Stay tuned.

-Saftgeek

F1nut

Have you checked the lead wires that run from the terminals to the voicecoil for breakage, a cold solder joint or if they are touching each other?

gdb

F1nut wrote: »

Nothing like jumping to conclusions. You don't know that the magnet has shifted from what he has said so far and of course, you didn't bother to ask him for more information. I know...hell, we all know you don't realize it, but there are other possible causes for his problem.

So, why don't you ask for more information? Do you even know what to ask?

BTW, other than the known dead drivers you purchased to experiment on, exactly how many good ones that you have owned had the magnet shift while in use? While in transit?

How would you like a nice big cup of ST__Up ? You probably deny that the guy who died today,ever walked on the Moon too.:rolleyes: The NUMEROUS posts/threads about locked drivers on this forum were NOT all originated by me, regardless of what you may believe.

Saftgeek

I did check the leads. They are intact and not loose. The ohmmeter registered 0... From a previous post I believe they were supposed to register 3 and some change.

-Saftgeek

mesquitehead

If the speaker is bad do not buy the current replacement from Polk, I did and I regretted it! Find a good original used one on ebay or here on the site.

F1nut

Ok then, drop a PM to geppy1. He comes up with an incredible amount of SDA parts.

F1nut

gdb wrote: »

How would you like a nice big cup of ST__Up ? You probably deny that the guy who died today,ever walked on the Moon too.:rolleyes: The NUMEROUS posts/threads about locked drivers on this forum were NOT all originated by me, regardless of what you may believe.

Bucking for that Clueless F of the Internet Award again, I see. Don't sweat it, you're a shoe in.

PolkieMan

Well you can buy a new one to tide you over it's only $48.
Tell them your a Club Polk Member, ask for Helen Yarbrough.
I would so much like to see a technical comparison between the old and the new drivers.
And I tested each driver with the amp turned down very low.
Mine had a dead 6510 a lot easier to find.

mesquitehead wrote: »

If the speaker is bad do not buy the current replacement from Polk, I did and I regretted it! Find a good original used one on ebay or here on the site.

Saftgeek

Polkie - Technical comparison... not so sure I'm qualified for that. Way too many car stereo sessions to even begin to offer any sort of review of anything over 13khz. I was hoping to see a picture of the driver to see if it looks any different than the old driver. If not, I may just do what you suggest... replace the driver and wait like a lion in the grass for an original replacement to come up on CL, Ebay or on here.

If anyone can link up a picture, I would greatly appreciate it.

-Saftgeek

mesquitehead

A few years ago when I blew one of mine I ordered one from Polk, what I got was a cheap lesser version of the original...I sent it back and found some new old stock at a shop in Milwaukee, I even bought an extra just in case. Ken S. and I had a long conversation about the outsourcing of these drivers.

Saftgeek

Mesquitehead- "bought an extra just in case." That sentence screams out to me... Any chance you still have it and want to help a total stranger out? I could promise you my first born, but it's too late now. He eats a lot and really isn't in to stereo equipment. If you're looking for someone to play Battlefield 3 with, we might be able to work something out. He seems to enjoy that.

Thanks for the heads-up on the replacement driver.

-Saftgeek

mesquitehead

Call these folks http://www.oaktreevintage.com/Polk-Audio_Speaker_Parts.htm I don't know if I could even find my extra one right now.

F1nut

Yes, the new drivers look a little different. The dust cap covers a little more area, so that you don't see the leads. The rubber surround doesn't have little notches cut out at the holes for the screws. The surface of the cone is not as shiny, nor as sticky. Spec wise, they are suppose to be the exact same.

A few years ago when I blew one of mine I ordered one from Polk, what I got was a cheap lesser version of the original...

What other company makes the effort to supply 20+ year speakers with drivers? Geesh!!!

mesquitehead

F1nut wrote: »

Yes, the new drivers look a little different. The dust cap covers a little more area, so that you don't see the leads. The rubber surround doesn't have little notches cut out at the holes for the screws. The surface of the cone is not as shiny, nor as sticky. Spec wise, they are suppose to be the exact same.



What other company makes the effort to supply 20+ year speakers with drivers? Geesh!!!

Let me make it a bit more clear for you .....it was a piece of sheet, as I mentioned Ken and I spoke about outsourcing and such things relating to the replacement drivers! I realize you are the gawd of all things Polk in your own mind and seem to have a penchant for being a smart **** but fact is it was an inferior product. Considering the buyout by DEI and the age of the speakers I certainly would not expect them to have 20+ year old drivers in stock, it doesn't take a genius to figure that one out. As opposed to being a **** I actually posted a link where they guy might actually be able to find an original driver, it's called being helpful. You should try it sometime.

F1nut

I've seen them in person, I know exactly what they look like. Hence, my HELPFUL description to answer his question. Where was yours? The fact is they are nowhere near as bad as you make them out to be and there's been plently of folks that are happy with them.

Whether you realize it or not (obviously not) you come across as an ungrateful cry baby. Try to work on that.