Polk Binding Post Replacement

PolkFanVA

I am thinking about upgrading the binding posts on my RTA 12B's, any advice? I am not the best with an iron but I can make a decent solder joint I suppose. Seems like a relatively easy upgrade but I was curious if there were any common pitfalls or things to look out for. I don't want to melt the cup or anything. I tend to overthink everything but would love input. I come from more of a car audio background 10-15 years ago in my youth and am really just getting into the whole world of HiFi. I really need to find less expensive hobbies, but where is the fun in that.

pitdogg2

Fwiw you solder it outside of the cup. Then put it back in cup.

Cardas post are top notch and require a ton of heat...

PolkFanVA

Thank you pitdogg2, I will have to pull the cup and look again. I don't like the idea of requiring a ton of heat. With the crossover on these speakers attached to the cup I'm more inclined than I was before to just suffer the poor binding posts until I can send them out for a full refresh.

pitdogg2

Well you'll need to remove both to do it right. Honestly think about ring shanks and screw wires to the post. I've used that method twice. Gold plated rings crimped to the wires.

I've used that method more than once.

PolkFanVA

I was thinking rings or spades, or just stick with 16GA wire as I have a relatively short run. Just so odd that I could get 10GA or larger wire through my amp with no issues but the speakers I can barely get 16GA through. If just one strand is out of place I end up with an end that looks like when our kids were infants eating spaghetti...

Gardenstater

11.5 awg Cardas Litz fits just fine in the #84523 Crimp On Gold Plated Ring Terminals, which are sold as being for 16-14awg (Blue). You have to open up the 1/4" stud holes to 5/16" with a tapered reamer or by drilling carefully while it is held down securely to a block of wood. I got mine at an Advance Auto Parts. I had a hard time finding a store that had them in stock. I think the stores will order for you and you can pick up at store.

Also, it may or may not be an issue for you, but if you're OCD like me you might not want to use the same nut on the Cardas Binding Post that secures it to the XO Cup, to also make the electrical connection. I prefer having that be between 2 nuts and they only give you one gold plated brass nut (5/16"-32tpi), or at least that *was* the case when I bought mine. I complained and eventually got sent 4 more gratis, which was nice of them. Thin Panel Nuts are available but not with gold plating. If you get the short Cardas binding post, you probably will not have room for 2 nuts and a brass washer (I bought), because the crossover cups are made of pretty thick plastic. They are 0.200" thick on my 7B's. As it turned out I couldn't use the 2nd nuts and I wished I had ordered the longer binding posts.

PolkFanVA

Gardenstater, right now I have factory Polk binding posts. I was just curious the level of difficulty in upgrading them and I think it might not be worth the trouble. I would agree with you that using the nut that secures the post to the cup is not as desirable as having a double nut setup. I will stick with my smaller gauge wire for now and look at what ring or spade terminals will best fit the factory posts if/when I want to step up to larger wire. After doing some reading with runs as short as I have and the power my amp puts out I don't think I will benefit much from larger gauge wire now anyway.

Gardenstater

It's not the easiest mod to do, especially if you use 11.5awg Cardas Litz which is difficult to work with AND you retain any external fuse blocks (I guess not an issue for your speakers). I'll let you know what the benefit is tomorrow when I complete the installation on one of my speakers, but I think you would be surprised, despite the short runs involved. I will tell you that the benefit was HUGE when I changed out the stock driver wires for 12awg solid UPOCC Neotech on my MW6500 and 15.5awg Cardas Litz for my Peerless Tweeters. Those were only 24" and 19" long runs.

PolkFanVA

I look forward to hearing your results. I have been wondering about the small gauge internal wiring myself. I should have never read anything on here and certainly never signed up. Now that the genie is out of the bottle I guess you can't put it back or something like that. Time to start pumping some (soldering) iron as it were...lol I crack me up.

F1nut

These are great and no soldering required.
https://www.partsconnexion.com/WBT-75718.html

Jazzhead

I replaced the original posts with Cardas posts and heard noticeable improvement. My binding post cups were cracking from age, so I had a local machine shop fabricate some heavy aluminum discs for replacement. I replaced the internal wire with 14 gauge stranded Neotech UPOCC wire while I was in there. I had to employ my vintage Weller soldiering iron to get fast brute force heat to do the solder job. It was still tricky as you don't want to get the plastic part of the Cardas posts hot. All these (and more) mods add up to impressive sound (the Rabbit Hole).

PolkFanVA

Jazzhead, Did you use the NEI-3003 III? I was looking at the website and wasn't sure which you used. Just looking to see what the prices might run.

pitdogg2

http://www.soniccraft.com/product_info.php/cardas-ccgr-binding-post-p-1390

DaveHo

F1nut wrote: »

These are great and no soldering required.
https://www.partsconnexion.com/WBT-75718.html

Affordable, Hahahahah. Yes they're nice.

Gardenstater

If I had to do mine again, I would choose this one. The longer 5/16 threaded section would've allowed two 5/16" jam nuts (for 5/16" ring terminals), and there is the other option of using the 3/16" threaded section with a 3/16" ring terminal. If you wanted to solder you still could with the small hole in the end.

The other binding posts are either too short or too long for my application. The only way I made the short one work with ring terminals was by sawing and filing off the bosses on the glass filled mounting base, and by eliminating their thick teflon washer in favor of a brass one, and by only using the one jam nut they supplied.

http://www.soniccraft.com/product_info.php/cardas-ccgr-pc-binding-post-p-5194

Jazzhead

Polkfan:

I used these Cardas posts from SonicCraft:

http://www.soniccraft.com/product_info.php/cardas-ccrr-binding-post-p-1668

At the time I wanted the detail of silver/rhodium, but with later mods if I had to do it again I might go with gold.

F1nut

DaveHo wrote: »

F1nut wrote: »

These are great and no soldering required.
https://www.partsconnexion.com/WBT-75718.html

Affordable, Hahahahah. Yes they're nice.

I get them from HiFi Collective, about $25.00 a pair.
http://www.hificollective.co.uk/binding_posts/wbt-0708-nextgen-pole-terminal-1.html

PolkFanVA

Thank you all for the input.

Jazzhead

Polkfan:

As for wire, I used the stranded Neotech 14 gauge listed in the "chassis" wire category:

http://www.soniccraft.com/product_info.php/neotech-stranded-upocc-copper-in-teflon-14-awg-red-p-1873

Gardenstater

Here's a couple photos showing the ones removed from my left speaker and the ones that are ready to go into the right speaker. Initial listening impressions are: a deeper soundstage, cymbals are crisper and more shimmery and decay times are longer and brushes on drumheads are highly resolved. Some improvement in bass, depth and resolution. The one binding post has a test lead from my ribbon cables that I made to see how it would go converting my ring terminal leads on my cables to spades and how they would fit. Came out perfect so went ahead and moddded my ribbons.

PolkFanVA

Looks good, maybe I will dive in after I build my workbench.

Gardenstater

Looks good. Sounds great! A work bench is nice. I did the work up by the speaker itself, using a Workmate with a piece of particle board on it as a work surface, but I did use my desk as supporting surface area for accumulation of tools and parts lol. Again no WAF involved

Gardenstater

More info. just for completeness.

Polk tweeter supply wire (black, through Littlefuse #357 fuse block) was 16x30awg = 18awg, 2 x 7" = 14" long. Now 11.5awg Cardas Litz, 2 x 4-1/4" = 8-1/2" long.

Return wire, white, was also 18awg, 7", now 11.5awg Cardas Litz, 5".

The pre-existing holes in PCB did not have to be enlarged.