Ideas for cleaning 3 and 7 pin XLR pins and sockets

GroupDIY Audio Forum

Help Support GroupDIY Audio Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
I work with metal in my day job, casting finishing and restoring bronze sculpture and other art works. We use citric acid to clean off oxidation from sensitive surfaces. It does not in any way harm the metal, but dissolves and removes only the oxides.
I've successfully cleaned contacts in scores of old audio-gear by a soak in a mild solution and rinse in demin water or IPA (not the beer).. All the devices are still working, to the best of my knowledge.

Happy tinkering...
 
This has been a very informative thread for me. Lot's of great ideas. Thank you everyone.

MicMaven,
Thanks for the tip on the ham keys. I've got a bunch of keys that have been sitting for years in a box that I need to clean up. I order some of those cleaning boards before to do that. I want to clean my Vibroplex BY-2 gently.
I'm guessing I will use them for lots of other stuff too. They are a very reasonable price.

rh001, WPA Brown Stuff
I think this is what I was looking for to clean both the mic pins and sockets (the 7 pin tube connectors are really small).

My thought is,
Pins: get a thin tube just slightly large inside diameter than the pin. Fill the tube with Brown Stuff, then slip the tube over the pins and rotate, ...
Sockets: use a torch tip cleaner that is slightly smaller than the socket, coat it with Brown Stuff, then insert and rotate, ...

I think that will work exactly really good.

thanks all !!!
 
excepting those that are extremely dirty and/or corroded, lots of those out there.
I've never seen a tube that had contacts so corroded that more than extracting them and reinserting them was necessary.
If they are so corroded/dirty, I would think the rest of the unit would also be extremely damaged.
I have an amp I built in 1967 and has been in storage between 1980 and 2020. I extracted all tubes and reinserted them, then turned the amp on. It came to life quickly without a click or pop. After about an hour one of the caps started to blow gas. I recapped the whole amp, but the tubes are the same old ones.
 
I've never seen a tube that had contacts so corroded that more than extracting them and reinserting them was necessary.
If they are so corroded/dirty, I would think the rest of the unit would also be extremely damaged.
I have an amp I built in 1967 and has been in storage between 1980 and 2020. I extracted all tubes and reinserted them, then turned the amp on. It came to life quickly without a click or pop. After about an hour one of the caps started to blow gas. I recapped the whole amp, but the tubes are the same old ones.

I have lots of New Old Stock / New In Box examples with very dirty pins. Many tube dealers will now sell you this with no mention. Cleaning is a must in those cases.
 
Why? Do they not clean up when inserted?

You would not try that if you saw them. You would polish/clean to some degree first. I do not get the impression you deal with extremely old / aged / poor condition amplifiers or parts, so this may be hard to imagine. Buy NOS 1930's tubes for restorations, you might start to get the idea.
 
Why? Do they not clean up when inserted?
World Pro Audio Brown Stuff
Not really worse than applying an abrasive, which will also attack metal as well as the oxide.
Remember Ag and Au are quite resistant to most chemical agents, when Ag2O is dissolvable in acids.
I would agree that treating audio connectors with an acid or an abrasive is a bad idea.

What do you think is the magic agent in DeoxIt?

Deox products existed way before the idea of electric contact, relying on the use of acids (mainly phosphoric and hydrochloric).

Strange concept. Actually, the hardness of silver oxide is very similar to that of metal silver, so cleaning oxide removes metal as well.

Brown Stuff's active ingredient (Dichloro -1-Fluoroethane, also known as refrigerant R141) is a very strong solvant. It has no chemical action on silver oxide, neither on metal. That's why the recommanded procedure requires physical abrasion.
Use of refrigerants for cleaning PCB's is well known, because they dissolve many organic matters, a physical action, but are chemically relatively neutral.
There is no Dichloro-anything in Brown Stuff...it's actually non-toxic, even if you eat it. I don't think there is a magic agent in Deoxit cuz it doesn't work very well...it seems it just temporarily masks the problem with mineral oil. Johson&Johnson Baby Oil will likely work as well as Deoxit. BrownStuff does not remove the contact metal...except in some cases of very old and thin or poor gold plating some of the gold will rub off if rubbed to vigorously, but vigorous rubbing is not needed with Brown Stuff.
 
This has been a very informative thread for me. Lot's of great ideas. Thank you everyone.

MicMaven,
Thanks for the tip on the ham keys. I've got a bunch of keys that have been sitting for years in a box that I need to clean up. I order some of those cleaning boards before to do that. I want to clean my Vibroplex BY-2 gently.
I'm guessing I will use them for lots of other stuff too. They are a very reasonable price.

rh001, WPA Brown Stuff
I think this is what I was looking for to clean both the mic pins and sockets (the 7 pin tube connectors are really small).

My thought is,
Pins: get a thin tube just slightly large inside diameter than the pin. Fill the tube with Brown Stuff, then slip the tube over the pins and rotate, ...
Sockets: use a torch tip cleaner that is slightly smaller than the socket, coat it with Brown Stuff, then insert and rotate, ...

I think that will work exactly really good.

thanks all !!!
Hi!

You should give WPA Brown Stuff a try...you will not believe it's effectiveness. No need for tools to clean small pins or sockets...just coat the pins in Brown Stuff, the squeeze a little in the sockets and mate and un mate the connector 10 or 20 times with a little bit of rotational torque. Rinse with CRC Electro Clean or IsoPropyl and some compressed air. A coating of WPA Clear Stuff is also recommended.
In the case of the ham keys you can put a dab of Brown Stuff on the key contacts and on some plain 1/32" to 1/16" cardboard and use the cardboard as a tool, running inbetween the contacts 10 or 20 times. Rinse as noted above, and even run a piece of clean cardboard between the contacts to be sure to remove all the Brown Stuff.
With sliding contacts...most switches used in audio have sliding contacts...an imperceptible amount of Brown Stuff residue does not interfere but keeps on cleaning. When contacts come together without sliding then it's best to remove all traces of Brown Stuff. Even in relays where there is a tiny bit of slide as contact is made complete removal of Brown Stuff is advised.

BtW, I've made more pro audio repairs than anyone living, perhaps anyone who has ever lived. I am the Yuzuru Hanyu of pro audio repair.
 
Last edited:
Yup,
Thanks for the follow up on 'residue'. I worry about that (probably more than I should).

Also, I like the idea of brown stuff on paper/cardboard.
 
World Pro Audio Brown Stuff

There is no Dichloro-anything in Brown Stuff...
You're right. It's actually the Clear Stuff that contains MS938 aka Dichloro -1-Fluoroethane.

Back to the subject, which is cleaning XLR pins, I still maintain that there is no technical need for cleaning oxidized contacts, only cosmetic reasons.
If contacts are pitted, that is no more the basic Ag oxidation, it's due to strong chemical or mechanical actions. then I don't see why they should not be purely and simply replaced with new ones, because they will never offer a safe contact.
 
Correction: I might have written that WPA Clear Stuff is MS-938...meant to say MS-739 and thus has no Dichloro. MS-938 works well too but I'm not sure it's still available.

Clean xlr pins and sockets is a prohylaxis against random little ticks and (if very oxidized) loss of clarity or just loss of an intangible something you only notice after cleaning. No need to replace xlrs, save lots of time and money by cleaning with WPA Brown Stuff. Clean contacts are a must...for instance, relay contacts. Everything should be clean like in Japan....Only in Japan and France do people have clean arses, but overall Japanese make French seem messy and dirty. Public toilets in Japan are clean.
 
Back
Top