DIY Audio Projects Forum

Hi.

Yes, Ag when exposed to the air will be tarnished by sulphur (oxides) gases inside the air. Sooner or later depends how pulluted is the city airs (lots of taffics will produce tons of S02 gases).

Even sterling silvers (low purity silvers) used to made rings & ornaments tarnish, let alone high purity silvers. Pure silver should be kept away from air to prevent tarnishing.

That's the basic reason why I have to have pure silver wires stored in air-tight flexible tubing of Teflon (again for Teflon's low dielectric loss & high wave propagation velocity).

With Teflon tubing inserted inside a heat shrink tubing (600V UL/CSA), the doube walled protective cover should give enough airtightness to the whole run of cable.

All we have to focus on is how to terminate the cable ends to the end plugs so an effective airtight termination can be made permanently.

Hint:- Silver solder to cover the entire joint so that the silver wire be 100% buried inside the solder.
Extra very short lengths of heat shrink tubings, overlapping each other, to seal up the Teflon/heat shrink tubing ends onto the connector innart with hot air gun. You'll be surprised how effective such overlapping heat shrink covers will be in airtighting the termination.

It is thinking plus handcraft.

c-J

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"If the facts don't fit the theory, change the facts" quoted Albert Einstein.

Hi c-J,

Good info.

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Kind Regards,
Dinesh

Some of my diy audio projects:

• Elliot Sound Products - P3A 100W Amplifier
• TMM 2.5 Way Loudspeaker with Scanspeak 18W8546
• 2-Way MTM Loudspeaker with Scanspeak 21W8554 and D2904-7100

Heya c-J,

Have you perchanse assembled some borrowing some gas from say, a MIG welder to try and scoot the oxygen out?

Was just an idea that popped into my head.

I know a fellow who used mineral oil and clear tubing and it worked well.

Cheers!

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-= Gregg =-
* Ratings are for transistors - tubes have guidelines*
Home: GeeK ZonE
Work: Classic Valve Design

Hi.

Yes, there is always no harm to expell oxgyen out from the tubing holding the bare conductor wire, be it pure copper or pure silver.

By shrinking up the outside heat shrink tubing with a hot air gun so that the inside tube (mine being Teflon as already said) gets tight support without tossing losse inside the outside tubing. While heat up the outside tubing, the moisture inside the air inside the inner tubing will be dried up.

Another reason, which I skipped to mention, why I always use Teflon tubing, is Teflon is a high temp material can handle up to 200C. So when heating the outer protective heat shrink tubing, the inner
Teflon tubing would not be destroyed by the heat of the hot air gun & at the same time, protect the conductor wire inside.

While shrinking up the outer heat shrink tubing by a hot air gun, make sure both ends of the tubings are open so that the moisture inside the inner tubing is expelled rather than forming a vacuum, defeating the very purpose of trapped the dry air inside the inner tubing as the dielectric
for the conductor wire inside.

c-J

_________________
"If the facts don't fit the theory, change the facts" quoted Albert Einstein.

I needed a short inter-connect to go from my Cowon S9 player to my new headphone amp. I used four strands of wire-warp wire, two blue earths, one red and one black.

These were heavily twisted together in a drill and heat shrink tubing placed on top. At the destination end only one earth (blue) is terminated. Gold connectors used. Additional short lengths of heat shrink were placed on the ends for durability, silver solder used.

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Projects: "Abstinence" - 6EM7 power amp | "Number 9" - Tube and Chip Integrated amp | "Arabella" - 6EM7 amp on Acacia wood ]
Website: [ retro-thermionic ]

If you are a member of the flat earth society or the "Thin is in" for inter-connects you may like these. Due to the fact I have built three headphone (HP) amps in the last three weeks and there is no quality 3.5mm to 6.5mm stereo inter-connects I have a made a few pairs of my own. The three HP amps are two CMoy style chip amps on 18V and one K272B (kit from Oatley soon to be released). The K272B is JAN6418 based. I think there is something just unique about a portable triode HP amp which runs on a 9V battery. Back to the cable build.

These cables call in a few techniques I like, appear to make sense and are very easy to employ.

1 - use wire wrap wire to make the inter-connects.
2 - heavily twist two earths and one hot wire in the cable but only terminal one earth at the destination end.
3 - for the player to HP amp two earths and two hot wires but only terminate one earth at the destination end.
3 - heat shrink tube over the cable and shorter heat shrink ends for durability.
4 - isolate one side of the crimp tags with a few mil. of heat shrink in the RCAs (so when they are crushed down they do no form a conductive loop).
5 - use WBT 4% silver solder.
6 - use cheap flimsy RCAs.
7 - test for shorts and continuity with a meter at every step.
8 - try not to enjoy these great sounding ultra-cheap inter-connects too much.

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Projects: "Abstinence" - 6EM7 power amp | "Number 9" - Tube and Chip Integrated amp | "Arabella" - 6EM7 amp on Acacia wood ]
Website: [ retro-thermionic ]

Here are some inexpensive cables I made. Twisted wire-wrap wire - two earths and one hot wire. Only one earth is connected only at the destination end. Light weight connectors are used to reduce eddy currents and magnetic issues in the RCAs. WBT silver solder used for solder connections and heat shrink tubing over the lot. The strain clamp in the RCAs has one side insulated again to stop eddy currents forming.

There is no real shielding other than the second earth wire which acts as a drain to keep noise back at the source rather than pasting it on.

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Projects: "Abstinence" - 6EM7 power amp | "Number 9" - Tube and Chip Integrated amp | "Arabella" - 6EM7 amp on Acacia wood ]
Website: [ retro-thermionic ]