Polk 5jr Speaker Fixes

GospelTruth

Back Story
This past summer we went to go and see a band called Pink Martini. We've seen them a handful of times and if you haven't seen them and get the chance - do it. My first time seeing them live, I was drawn in to the performance and have been a fan ever since. Anyway, saw them again with our friends and of course they are selling their albums on vinyl. So my friend buys one to get autographed by the band. He doesn't have a turntable, stereo, speakers - nada. His wife picks up for him one of those USB connect to the computer turntables so he can play the music. Needless to say, I told him that I could get him a set up for less than $150 that would be WAY better than what he has going on. So begins my quest to get him a simple setup through the local craigslist. This won't be fancy by any stretch, but in my search I'm looking to get a turntable, receiver, speakers and maybe a CD player. And so begins this journey...

Purchase
So I picked up a set of Polk 5jr speakers on the local Craigslist. The gentleman wanted $40 for the pair, but I offered $20 and he let them go. He just wanted to clear out his garage as he was moving out of state.

The speakers looked to be in decent shape with some nicks on the back edges and grill cloth coming loose. I have some glue to fix the speaker cloth. Speakers themselves were dusty, but nothing a little Windex couldn't fix. Push test was good (no air leaks) and no scratching sound from the drivers when pushed in (frozen drivers). Cleaned them up and hooked them up to the receiver in the living room. Everything works and sounds pretty good actually.







Looking for your thoughts
So I cleaned up the drivers with Windex. Vacuumed the grills and cleaned those also. Glued down the grill cloth that was loose around some of the edges and they look pretty good.

One issue on one of speakers though is that the corners have a slight separation on one of the speakers. This is on both the front left and right of the speaker. Upon further investigation, it looks like the front baffle of the speaker is slightly pushed in compared to the top (and compared to the other speaker. It's almost as though it got pushed in and when pushed, it caused the bottom corners to separate. There is nothing I can see damage wise that would have done that though. I removed the passive radiator and the back plate and the glue along the edges all looks solid. It doesn't appear to have been pushed from the inspection there.


Bottom of the baffle where there is a little more of a gap with the box.


Top corner of baffle where it's pretty much flush with the speaker box.


You can see the split in the lower left corner easily without the grill.


Bottom of the other speaker where the baffle looks close to flush with the box.

Just wondering what your thoughts are. I might just try to give it a tap with a hammer from the inside and see if it pushes out. Not the end of the world, but I'm kinda anal and like things to look perfect. It's not something totally noticeable with the grills on. Do you think I should just leave it alone? I could also just fill the cracks with some wood putty and get a stain pen to kinda match just to hide gap. Not ideal, but might be less sightly than leaving it alone. I don't want to make this a project as it's for someone else, so cheap is what governs this project.

Not planning on upgrading the SL2000 tweeters. If he wants to do that, I'll gladly do that for him, but right now I'm trying to build this system cost effectively to show his wife he can have something nice for not much cash. Same goes for the crossover - leaving this stock at present.

One thing I would also like your thoughts on are some rust on the tweeter bolts. Don't know if there is an easy way to remove it without either taking off the black coloring of the bolts or having to remove them individually. I could always use bluing to get the black back if need be - which I have on hand. Just would like some thoughts on that as well.




An Oddity
Finally, when I opened up the one speaker, the passive had a date of May 10, 1996? I thought this model with the SL2000 was from the late 80s early 90s. I have another pair of 5jr+ with the SL2500 that I bought around 1991. So I would think these speakers would predate that. Just a little odd based on model years.




Anyway, your thoughts are welcome.

F1nut

Try to close the gap using woodworking clamps. If it closes take the clamps off, inject Titebond wood glue and reclamp for 24 hrs. If it doesn't close, you're SOL.

You can safely remove two screws at a time, clean the rust and spray them black.

That PR issue is odd. It has to be a replacement.

westmassguy

Rusty screw heads and swollen joint indicate they were stored in a damp location at some point. Probably a basement or garage floor. Try the clamping that @F1nut suggested, but more than likely it will not close the gap. Re-sealing the cabinet internally is your best bet.

GospelTruth

Thanks guys.

The cabinets are sealed inside from what I can tell as that has not been compromised. It's just the corners that became separated, not the entire bottom of the speaker, so it seems like just the front bit. Probably saw some moisture as suggested. Not bad though. The bottoms aren't warped or anything so seems a bit odd. The guy lived in California before along the coast. I've seen that with salt water on screws like that before because of the salty air. Must have had a little too much moisture in the air for the one speaker.

Tried to clamp them down, but they don't seem to budge. I may just fill will wood putty and put a dark stain on them to kinda hide that. Not the end of the world.

Thanks for the advice on the screw heads. I'll do that as soon as the holidays allow.

I decided to open up the other speaker and check the date and the passive there as well. Same exact date which I found odd. Doesn't seem like they were ever opened based on how the screws looked and how "stuck" the passive was when trying to pry it loose once the screws were out. Maybe they just did a typo on the label.

The drivers however were dated November 4, 1991. MW 6502. Those appear to the the right drivers for the model and year.

Again, thanks for the input.

F1nut

That doesn't look like water damage. It's the type of damage one would see as a result of the speaker being dropped straight down. You'd have to clamp top to bottom and side to side to get that to close. There's plenty of vintage Polk's out there with rust on the screw heads and on yours it's only on a few, so I doubt salt air was the cause. They were likely exposed to a corrosive before mounted.

GospelTruth

Thanks for the reply. I'll give it a go with the clamps sometime in the next week and do the top-bottom side-side thing. Hopefully that works.

K_M

@GospelTruth I realize you said this is a very budget conscious re-do, but replacing the tweeter cap (Forget if one or two on this model) is one of the biggest improvements you can make.

Literally any brand will be far better than the 30 year old ones in there now.