1.2 1.2tl wiring question?

Toolfan66

The tag on the back of my 1.2's makes no sense.

the wire nuts on the back are in the same position as what the tag on the back says they should be, but if i follow the wires from inside the speakers my positive side is going to the negetive side of the crossovers and visa versa with the negitive side.

I know there is another thread here on this same issue, but I don't get it. I never changed the wire nuts on the back hell I have never taken them off.

But as I see it the tag on the back is wrong.

So as I see it I have been powering these wrong since I have had them. I really wish I would have looked deeper into the wiring to make sure everything was right. but I guess I assumed the wiring was correct just looking at the tag on the back and as I did nothing to the harness as well I left it stock.

So am I right that the Positive side of the wire nuts should go to the Positive on the crossover? and visa versa for the negitive side?

I am having a hard time thinking that we have had a handful of speakers wrong all along for 20 years.

On another note if anybody does a 1.2 to 1.2tl crossover upgrade the tweeter wires will wire opposite what the 1.2's are. I did confirm this with Polk's great CS.

RichCanDo

TOOLFORLIFEFAN wrote: »

On another note if anybody does a 1.2 to 1.2tl crossover upgrade the tweeter wires will wire opposite what the 1.2's are. I did confirm this with Polk's great CS.

This confirms what I had written of in another thread. If you upgrade the crossover from 1.2 to 1.2TL then you also have to change the pin configuration on the Tweeter Array Connector to match the 1.2TL schematic. Wiring tweeters "opposite what the 1.2's are" is not really correct. When changing the wiring, the white wire from each tweeter must connect to the correct pin on the connector.
Post #128 http://www.polkaudio.com/forums/showthread.php?p=1166975#post1166975

I think the above link to Post #128 should be made a sticky to help those upgrading to the TL model.

Regarding the incorrect binding posts phasing. I would correct it. Positive binding post connects to (+) on the crossover, Neg to (-)

The wrong phasing may have been caused by Polk using labels from older models for new models as mentioned in other threads.

I would not just swap the red and black markers on the binding posts as others have done. If you do this, the posts no longer match the wiring shown on the label. I would undo the wires on the posts and connect them to the correct posts. - It may be easier to swap the pins at the connector to the xover board, but then you have the wire color code wrong. If you do this, you could mark the wires with the correct color.

michaeljhsda2

"So am I right that the Positive side of the wire nuts should go to the Positive on the crossover? and visa versa for the negitive side?"
Correct

"I am having a hard time thinking that we have had a handful of speakers wrong all along for 20 years."
Sad but true.

Toolfan66

Changing everything around really help the SDA effect. I feel kinda stupid really I know it's all a lack of experiance with the SDA's as they did sound great, they just sound better now.

But after hooking my 1C's up a couple of weeks ago I had a feeling something was wrong.
Then RichCanDO,michaeljhsda2 started the other thread and it got me looking into it.

Rich I will have a price on your plates this week, I have been very busy at the shop and it slipped my mind.

Thanks Guys.

RichCanDo

Thanks Larry for info about the plates. I am in no hurry. Just PM when you have some info.

Toolfan66

Well Sunday I pulled all the drivers and JB welded all the magnets, 16 drivers takes some time to do this. Last night I did undo the wires on the posts and connect them to the correct posts, the passive came in real handy to do this and the old hot glue was no problem to remove. and the tweeters are rewired as well.

all is good in what I can call my 1.2tl's now.

It made a big difference in imagery and sound. Now I feel the music wraps around me like my 1C's do. what is amazing is they sounded fantastic before all this came to light on the wiring, but now I see what I was missing..

Thanks again Rich, Talk about learning something here, this was a big one.

michaeljhsda2

Lasareath wrote: »

I guess I need to open mine up and check them out.

Is there a wiring diagram someplace that explains to the layman exactly which wire goes where in 1.2tl's ?

That would really help.

Thanks,

Sal

I have my 1.2 TL's on their backs with the drivers removed. I'll take pics of the wire sequence for the MW's. The tweeter wiring sequence that I mentioned in the other thread is exactly how they should be wired. My cabinet corners have areas where they never applied any hot glue in the first place!!!!! so I'm in the process of finishing that job. In addition, I'm installing dynamat extreme on all the MW's and the PR. I'm having trouble with the mortite on the gasket area....one tiny rope of it seems to be too thick so I'm not sure if I will just use the existing gaskets.

Toolfan66

just tighten the screws down a little at a time let the mortite flatten slowly.

You have 16 drivers so you can always go back to where you started. repeat step 2 or 3 times.

michaeljhsda2

TOOLFORLIFEFAN wrote: »

just tighten the screws down a little at a time let the mortite flatten slowly.

You have 16 drivers so you can always go back to where you started. repeat step 2 or 3 times.

I tried doing the mortite at the passive radiator area but the screws are now stripped out. I would rather replace the wood screws with t-nuts anyway like the 1.2's have but so far locating the t-nuts on HD and Lowe's website has proven fruitless. If I can't find the t-nuts and bolts (black) then I'll just fill in the holes with wood filler and just put the screws back in.

RichCanDo

michaeljhsda2 wrote: »

I tried doing the mortite at the passive radiator area but the screws are now stripped out. I would rather replace the wood screws with t-nuts anyway like the 1.2's have but so far locating the t-nuts on HD and Lowe's website has proven fruitless. If I can't find the t-nuts and bolts (black) then I'll just fill in the holes with wood filler and just put the screws back in.

I would use Hex Drive Flush Threaded Inserts with 8-32 threads for the PR. I would glue them in place though not required. The glue hardens the MDF. They are about 3/8" long, maybe 1/64" longer than the MDF thickness where the screws insert. These inserts are what Polk used on the drivers.

There are different types of these inserts for mounting in different materials. You want the Hex Drive Flush type which are for soft woods and MDF. I was looking for a place to buy these last night. Read Home Depot has them but not looked there. Grainger has them in packs of 100 for under $14.00. Some on eBay also, about $12 with shipping for 50. I am going to use them for my PR's as a few screws are stripped. My screws are in the MDF. I did not know T-nuts were used on 1.2's by Polk.

I would not use wood filler. If you do not want to use threaded inserts, I would drill a larger hole in the MDF, then glue a wood dowel into it. Drill a pilot hole in the dowel for the screw. But with inserts using machine screws you can take the drivers in and out as often as you want without worrying about messing up the threads.

RichCanDo

michaeljhsda2 wrote: »

I have my 1.2 TL's on their backs with the drivers removed. I'll take pics of the wire sequence for the MW's. The tweeter wiring sequence that I mentioned in the other thread is exactly how they should be wired. My cabinet corners have areas where they never applied any hot glue in the first place!!!!! so I'm in the process of finishing that job. In addition, I'm installing dynamat extreme on all the MW's and the PR. I'm having trouble with the mortite on the gasket area....one tiny rope of it seems to be too thick so I'm not sure if I will just use the existing gaskets.

I put Mortite on one speaker cabinet. Decided I am going to remove it and use the stock gaskets as they seal just as well. I rolled the Mortite out to thickness of the original gasket before installing it. Using Mortite makes it difficult to remove drivers later, and years from know they may not want to come out without tearing the MDF apart!

The MDF cutouts have a rough surface. I put 4-5 coats of polyurethane on the MDF cutouts for the drivers to make a smoother seal for the gaskets to mate to. Lightly sanded smooth between coats.

Also to help make a better airtight cabinet:
I put some Mortite around the studs that hold the top and bottom end caps on to seal the (8) 5/16" holes going through the cabinet.
I placed a 3/4"x3/4" piece of duct tape inside cabinet over each screw hole that mounts the 16 drivers, and holes for crossoverover plate screws. Not much air going to leak past a screws threads, but there are 40 screw holes in each cabinet not counting the 8 for the PR!

michaeljhsda2

RichCanDo wrote: »

I would use Hex Drive Flush Threaded Inserts with 8-32 threads for the PR. I would glue them in place though not required. The glue hardens the MDF. They are about 3/8" long, maybe 1/64" longer than the MDF thickness where the screws insert. These inserts are what Polk used on the drivers.

There are different types of these inserts for mounting in different materials. You want the Hex Drive Flush type which are for soft woods and MDF. I was looking for a place to buy these last night. Read Home Depot has them but not looked there. Grainger has them in packs of 100 for under $14.00. Some on eBay also, about $12 with shipping for 50. I am going to use them for my PR's as a few screws are stripped. My screws are in the MDF. I did not know T-nuts were used on 1.2's by Polk.

I would not use wood filler. If you do not want to use threaded inserts, I would drill a larger hole in the MDF, then glue a wood dowel into it. Drill a pilot hole in the dowel for the screw. But with inserts using machine screws you can take the drivers in and out as often as you want without worrying about messing up the threads.

Great info. Thanks. I found the name for the bolts "crown bolt socket cap" from HD. Now it's just a matter of matching up the bolt sizes with the inserts that you mentioned.

RichCanDo

Lasareath wrote: »

I guess I need to open mine up and check them out.

Is there a wiring diagram someplace that explains to the layman exactly which wire goes where in 1.2tl's ?

That would really help.

Thanks,

Sal

Post #4 on this link has a photo showing the tweeter wiring.
http://www.polkaudio.com/forums/showthread.php?t=88984
Use this with the 1.2TL schematic which shows which color wire connects to each pin on the connector and to the tweeters. I would print the above photo, then mark the wire colors on it as per the schematic. Note that the schematic of the connector is not layed out to look like the actual connector. Pin #1 is shown in middle of connector on the schematic, Pin #1 is actually at one end of the connector. And note (+) and (-) marking for the pins is correct on the schematic, but markings are wrong (reversed) on the actual board. (+ should be marked -, and - is +) This is IF the trace on your board is connecting the 4 (-) markings together. (The 4 (+) wires from tweeters should connect together at the board.)

You can also look at the schematic for the SDA SRS which shows the actual tweeter wiring. (Though it does not look like your harness, connections are the same.) Tweeter wiring is same for SDA SRS and 1.2TL.

NOTE: There is also a speaker wiring "diagram" with the schematics list under Vintage Speakers. This "diagram" does not show wiring, only wire color, phasing, and where to connect to each speaker. For the Dimensional Array one wire" has a "wire marker" that connects to the (+) terminal of the driver. On my harness the (-) not (+) wire has the "wire marker" which is correct for my harness. So the diagram is wrong for my harness. You must make sure correct wire goes to correct phase of each driver and do not trust this diagram in regard to the "marker." For the Stereo Array the diagram is correct for my harness in regard to the wire marker. (Marker is only a small piece of tape wrapped around the end of the wire terminal.)

My 1.2TL Serial #'s are both 61xx

RichCanDo

michaeljhsda2 wrote: »

Great info. Thanks. I found the name for the bolts "crown bolt socket cap" from HD. Now it's just a matter of matching up the bolt sizes with the inserts that you mentioned.

Get inserts for 8-32 screws. #10 screws are to big (diameter) and the inserts are to long for the MDF thickness. You have to be careful to install these inserts straight. If crooked you will have a hard time installing screws and can easily cross thread them. The inserts can be installed from the rear if you so desire but would be harder to get in straight that way. They make a special tool to insert these (size of a drill press!) or some people use a drill press to install them straight. You should be able to install them with an allen wrench, which is a metric size. A screw driver type driver would be easier for getting the inserts straight.

If you plan to use Cap Head 8-32 screws, make sure the heads are large enough to not go through the holes in the PR! About the only black screws you will find at Home Depot or Lowe's are cap heads.

RichCanDo

ERROR in post #15.
I wrote "Post #4 on this link has a photo showing the tweeter wiring." The photo is for DRIVER wiring so will not help with wiring the tweeters but will help wiring the drivers.

I also wrote to use the SDA SRS schematic for tweeter wiring diagram. It shows this but also shows the driver wiring which is what I really was writing about.
Sorry for confusion.

michaeljhsda2

Finished hot glueing the right cabinet last night....i'm amazed (and pissed) how much of the internal cabinet was never glued in the first place. Less than 50% of the entire internal cabinet had any glue!!! 2 of the 5 foot long inside corners had no glue whatsoever on them. Only one end of each of the 4 crossbraces had glue on them and the other end of the crossbrace was just floating in the air. wtf!!! I used mortite to seal each hole where the top and bottom plate bolt runs through (total of 8 holes). Ensuring that the internal cabinet is sealed would be one of the first things/tweaks that I would recommend doing on any Polk speakers.

michaeljhsda2

"I would use Hex Drive Flush Threaded Inserts"

I found these at the Do It Best hardware store along with the hex bolts. I think she called them "groin" nuts They are barbed so they won't pull out of the wood, however, I'm gonna glue them in just to be sure.

RichCanDo

michaeljhsda2 wrote: »

"I would use Hex Drive Flush Threaded Inserts"

I found these at the Do It Best hardware store along with the hex bolts. I think she called them "groin" nuts They are barbed so they won't pull out of the wood, however, I'm gonna glue them in just to be sure.

It is hard to tell from your photos because they are blurry, but the inserts look different than what I had recommended. Those you purchased look like they get hammered in. I would not want to hammer on the thin edge of the MDF where these get inserted as is to easy to break off an edge. Break an edge off the MDF and you have real problems!

The Hex Drive Flush Threaded Inserts I recommended look the same but they screw into the MDF creating their own threads. If one end of yours take an Allen wrench for insertion, they are correct as they screw into the MDF.

RichCanDo

michaeljhsda2 wrote: »

Finished hot glueing the right cabinet last night....i'm amazed (and pissed) how much of the internal cabinet was never glued in the first place. Less than 50% of the entire internal cabinet had any glue!!! 2 of the 5 foot long inside corners had no glue whatsoever on them. Only one end of each of the 4 crossbraces had glue on them and the other end of the crossbrace was just floating in the air.

It appears when the cabinets were assembled the front, side, top & bottom panels were glued together. The back panel installed last. Before the back panel was installed, a bead of glue was run around all the interior cabinet seams to add strength and seal any air leaks. The braces would have been installed at this point also, so all should be well glued on the front panel, with a bead of glue. Plenty of glue was used on the edges of the panels because even if it ooozed out it was only on the sides which later got covered with the decorative top, bottom and side panels.

It appears when the back panel was lastly installed they used a minimum amount of glue so that it would not ooze out onto the outside finished vinyl surface. To run a bead of glue around the interior seams probably was not done as when reaching into speaker holes to do so they would have left trails of glue all over the outside of the cabinet face. (Hot glue from a glue gun or glue pot.) They would also have to put glue on all the ends of the braces where they contacted the rear panel before it was installed. Things are done quicky during assembly so it seems they forgot to glue some of your braces, or did not use enough glue.

The seams on my rear panel were not tight in some places. In places where I could look into the open seam, I could see no glue so I ran a bead of wood glue around the entire rear panel. I also placed a bead around braces that did not have a bead of glue just to help strengthen them. I am sure the the cabinets were glued well enough by the factory for strength, I just wanted to assure there were no air leaks.

michaeljhsda2

michaeljhsda2 wrote: »

"I would use Hex Drive Flush Threaded Inserts"

I found these at the Do It Best hardware store along with the hex bolts. I think she called them "groin" nuts They are barbed so they won't pull out of the wood, however, I'm gonna glue them in just to be sure.

Instead of using the above threaded inserts which require hammering in, I chose the screw in type just like on the MW's.

RichCanDo

michaeljhsda2 wrote: »

Instead of using the above threaded inserts which require hammering in, I chose the screw in type just like on the MW's.

That's the ones I was referring to. They are called Hex Drive Flush Threaded Inserts. These are what Polk used on the drivers.