The SRS 1.2TL ..should I buy them?? :-O

Tony M

Good luck in finding the reason they sound thin and awful.

I hope it's an easy fix for you.

hauxon

I did notice something unusual before going to work this morning. The binding posts are different between the speakers. The right side are gold plated and the left one is not. Both look authentic though. The serial numbers are 155 apart (6935 and 7090). The one with the higher serial number has gold plated posts. Probably normal but rather strange for such expensive speakers.

BlueBirdMusic

I hope you are not planning to sell your 2B's that you purchased new in 1991.

hauxon

I wont sell them unless I get the SRS 1.2TL working properly. And I would preferably sell them to someone in my family. ...or just let my oldest daughter (16) have them in her room. ..but I'll keep 'em at least until the 1.2TL are good.

Here they are side by side in my living room. My 2B's look tiny all of a sudden

oldrocker

Congrats, monsters ain't they....

I've had mine for about 7 years, have done some minor upgrades.

I do get a kick out of when I've had them in the loop and people see and hear them for the first time.

Buddy of mine who is really short. I remember the first time he saw them, we both got a good chuckle as he said "they're taller than I am." I think they outweighed him by about 15 lbs also

Although I am currently demoing various new speakers, I'll always have a soft spot for my Polk's

DaveHo

I've never seen gold plated posts on that era of Polk. I think someone has been in there & didn't reconnect things properly. Bass that thin sounds like they might be out of phase.

daddyjt

The posts on the left speaker were most likely replaced. When I purchased my first pair of SRS, they had stainless steel wing nuts(!) on two of the posts. Removal of the “cup” allows easy replacement of the posts, which I’d guess someone did on yours.

Incidentally, if that did happen, and whomever did the work made a mistake in the wiring, that could explain the sound issues you are having.

Congrats on the acquisition, and welcome to the family:-)

verb

Congrats! Lots of folks here to help you on your journey! I also started with 2B’s and eventually got a set of SRS’s! Love em!

pitdogg2

verb wrote: »

Congrats! Lots of folks here to help you on your journey! I also started with 2B’s and eventually got a set of SRS’s! Love em!

and most all the craiglist, eBay and for sale stuff on Polk audio east of the Colorado river.

a little know fact......

pitdogg2

https://us.v-cdn.net/5021930/uploads/attachments/1/8/5/1/1/26689.pdf


https://us.v-cdn.net/5021930/uploads/attachments/1/8/5/1/1/26688.pdf


Your correct wiring diagram

hauxon

Thanks pitdogg2!

I tested the polarity on both speakers and it seems correct, plus terminal on the battery to the plus post (red) on both speakers send the woofers outward.

I removed the plastic speaker terminal plate to see if there was any sign of an amateurish job with the golden speaker posts but they look properly done.

Right speaker (gold plated posts)


Left speaker (regular posts)


Then I remembered hearing a little rattle when we rotated the speaker to the back for transportation. So I removed the passive radiator and voila! There lies a yellow capacitor on the buttom of the speaker cabinet (and a plastic thing for fitting the gill to the speaker, not missing from either speaker!).



The I took the crossover plate off and just as suspected one of the capacitors was missing (12uf from C5). My guess is that it must have fallen off when sombody tried to put the crossover plate back onto the cabinet, it is a tight fit.


I will make an attempt to solder it back to it's place. Not too optimistic on that working. Then I might desolder one of the 12uf capacitors (look like the same type) from my 2B crossover to see (hear) if the 1.2TL will sound like they should. Then I will have to order proper capacitors for each side until I upgrade the rest.

pitdogg2

Buy some @gimpod new boards and make your life easier. @westmassguy sells them for 100.00 i believe. They have more room for newer larger caps and are not nearly as cramped.
They're fantastic

michaeljhsda2

That piece of wood laying on the bottom of the cabinet is one of the cross braces and should be reinstalled. I would recommend reinforcing the other cross braces as well.

DaveHo

That might explain how the cap was taken out.

westmassguy

hauxon wrote: »

I did notice something unusual before going to work this morning. The binding posts are different between the speakers. The right side are gold plated and the left one is not. Both look authentic though. The serial numbers are 155 apart (6935 and 7090). The one with the higher serial number has gold plated posts. Probably normal but rather strange for such expensive speakers.

Both are original. Polk used both types.

hauxon

I managed to solder the cap back into the crossover and "voila!" they sound normal.

The soldering job was a mess so I don't trust it 100% and I will order two 12uF caps (for both speakers) after the weekend. I used ClarityCap ESA for the TL mod on my 2B's so I'll probably also order ClarityCap caps for my 1.2TL and keep the legs long enough so I can reuse 'em when I do the whole crossover thing.

I find the sound as it is now pretty good but the 2BTL sound more open and rounded, probably the RD0-198 tweeter. Since I plan to either have me 2B as secondary speakers or sell them I think the SL3000 would be good enough for them. Is there a one most important tweeter in the array I should put my 198 into. What tweeters should I swap out first?

verb

First thing (mod) I did was replace the 8 tweeters. Well, that's the only mod I've done, so far!

And, well done in finding the root cause of the issue! Congrats!

daddyjt

westmassguy wrote: »

hauxon wrote: »

I did notice something unusual before going to work this morning. The binding posts are different between the speakers. The right side are gold plated and the left one is not. Both look authentic though. The serial numbers are 155 apart (6935 and 7090). The one with the higher serial number has gold plated posts. Probably normal but rather strange for such expensive speakers.

Both are original. Polk used both types.

My bad - thanks for the correction. Never seen those before (on my 4 pair of SDAs, or anywhere else - except my Klipsch RF7s).

pitdogg2

I'm with you @daddyjt I've seen a ton and never seen any gold. That being said Dave has seen many many more than I. Heck my 2.3tl's are plain nickel, I've feel robbed.
Lol

Tony M

Fantastic!

I'm glad it was a simple fix!

Now get some new replacement tweeters when you can. I think you will need the highly praised rdo-198 models.

honestaquarian

Congrats on scoring the king of all SDA's! Glad to see it was a simple fix for you as well.
Now all ya gotta do is get used to that amazing extreme low bass capability!!!
There are truly few speakers which can reproduce the subterranean bass that these are capable of (and they all cost a LOT MORE)
I'm not just talking about bass in the boom range of 50 to 100hz. I'm talking about a couple of octaves below that in the 10 to 20hz range.

F1nut

Someone was playing around with those binding post plates. You can see the glue Polk used around the SDA socket, which is slightly yellow while the rest is modern hot glue. In fact, in the second pic you can clearly see where they didn't entirely cover the one binding post nut......not good. That will cause an air leak.

pitdogg2

F1nut wrote: »

Someone was playing around with those binding post plates. You can see the glue Polk used around the SDA socket, which is slightly yellow while the rest is modern hot glue. In fact, in the second pic you can clearly see where they didn't entirely cover the one binding post nut......not good. That will cause an air leak.

Right is right
Excellent observation skills

F1nut

westmassguy wrote: »

hauxon wrote: »

I did notice something unusual before going to work this morning. The binding posts are different between the speakers. The right side are gold plated and the left one is not. Both look authentic though. The serial numbers are 155 apart (6935 and 7090). The one with the higher serial number has gold plated posts. Probably normal but rather strange for such expensive speakers.

Both are original. Polk used both types.

I've never seen gold binding posts on any stock SDA.

westmassguy

F1nut wrote: »

westmassguy wrote: »

hauxon wrote: »

I did notice something unusual before going to work this morning. The binding posts are different between the speakers. The right side are gold plated and the left one is not. Both look authentic though. The serial numbers are 155 apart (6935 and 7090). The one with the higher serial number has gold plated posts. Probably normal but rather strange for such expensive speakers.

Both are original. Polk used both types.

I've never seen gold binding posts on any stock SDA.

I've only seen them on late production SRSs, not older SDAs or Monitors.

hauxon

westmassguy wrote: »

F1nut wrote: »

westmassguy wrote: »

hauxon wrote: »

I did notice something unusual before going to work this morning. The binding posts are different between the speakers. The right side are gold plated and the left one is not. Both look authentic though. The serial numbers are 155 apart (6935 and 7090). The one with the higher serial number has gold plated posts. Probably normal but rather strange for such expensive speakers.

Both are original. Polk used both types.

I've never seen gold binding posts on any stock SDA.

I've only seen them on late production SRSs, not older SDAs or Monitors.

The right speaker (with gold) is serial 7090 the left is 6935.

I found out that the 3rd tweeter from top is silent. I connected the RD0-198 from the 2B's and still no sound. The SL3000 from the 1.2 produced sound in the 2B so my guess is that I need a take a better look at the crossover. Maybe a broken solder jount or something.

hauxon

I took a look at the schematic for the SRS 1.2TL and found out that the 12uF capacitor that fell off (C5) is in line with the 3rd tweeter (the silent one). Seems like either the cap is done or the soldering does not make enough contact with the side where it was broken off close to the cap. So I need to replace the caps.

My plan is to use ClarityCap CSA for the crossover update process
so I've placed and order for 12uF CSA for each side and will reuse them when I start. I will probably start a new thread for the rebuild. The only "restoration" I've now is giving the wood a massage with Danish oil (as recommended by F1nut), looks beautiful.

Thanks for all the help and comments!

westmassguy

Clarity CSAs are very large. You might want to consider @gimpod circuit boards. A lot more real estate to work with, and much better quality than the original boards.

hauxon

I will probably be able to find a way to fit the single 12uF 250V CSA (38mm length ) onto the original board just to get the speakers up and running. I will however order Gimpods for the new crossovers.

Right now I'm looking into what parts to order and how much I'm willing to spend. Lot's of options to agonize over.

I've also been wondering how the Gimpods mount to the crossover plate in my 1.2TL's.

pitdogg2

They should be able to mount in the same place the old plate. They have the same hole pattern as old