Splicing In-Line Audio Cable

Aaron Becker

Well-Known Member
Apr 27, 2016
US - East Coast
I've seen many lengthy balanced lines extended, and extended again, and extended yet again. Not always ideal, but impractical to extend. I've done terminal blocks, and in-line soldering. The inline soldering is (to my knowledge) still in existence today. The terminal blocks were since removed for unrelated reasons, but both lasted 10+ years and worked fine, other than pre-existing issues that were unrelated to the extensions.
If you can, however, pull new runs, I highly suggest it, as it eliminates points of failures, as others have noted.
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Ben Stiegler

Well-Known Member
Aug 3, 2017
Sf Bay Area
I was considering soldering, trying to do in-line. A bit tedious but can be done haha

so soldering and shrink wrap would you say will be overall better than a terminal block?

I realize overall the “performance” is going to be the same, either will pass phantom power and signal I’d expect without noise issues for that shield splice
solder and heat shrink will be better cuz: 1) you can better maintain the twist and minimize the length over which the conductors are separated. 2) if you are lucky, you can save some of the foil by peeling it back and re-wrapping it. The best way I've found for this is to do offset inline splices.
A) push 2 pieces of shrink wrap up one of the cable ends. One should be say 2.5"", the other slightly larger diameter and 4" length.
B) prepare the cable ends: - carefully cut the reds so one is long, the other short; then do the inverse for the blacks. now you can splice and solder them (left to right) side by side, with insulation offset space between them, keeping them tight and parallel. Use this approach to mechanically join them before soldering: https://makezine.com/2012/02/28/how-to-splice-wire-to-nasa-standards/

C) once the red and black are soldered and cooled, pull the smaller shrink wrap piece down and warm it with a heat gun (not a match, plz) til it formfits the red/black splices.
d) Now join the drain wires - solder. If you were able to save the foil wrap, bring it back out to cover the splice area for EMI shielding.

E) finally pull the larger/fatter heat shrink down and encapsulate the whole splice.

F) connectorize the far end (extended), and TEST.

Terence Gray

Dec 4, 2013
I spent about 10 years doing installation and maintenance work on cruise ships, where inline connectors aren't allowed – not even within a rack. All the connections had to be made within a non-conductive outer "shell", so we used barrier strips for any points out in the "field" where wiring needed to be extended or split, and DIN rail terminals for everything leaving the rack. Every wire end had to be ferulled, all drain wires got a Teflon sleeve, and we used Hellerman sleeves to reseal the outer insulation where the conductors were coming out. To my knowledge, not one of the racks I worked on has had to be serviced for a terminal connection failure; nor were there termination issues with any of the equipment from earlier installations that we replaced.

After I started working on the ships I took the techniques I'd learned and applied them to the wiring of a G-Scale temporary model railroad display that I set up each year, which dramatically reduced the number of service call's I'd get.


Craig Hauber

Nov 6, 2016
Plentywood MT, Grenora ND
Crimped fork lugs on properly dressed wires to barrier strips were my favorite way to never have a call back. Back when one could get tinned pad barrier strips these were 60 year connections.
You forgot about lots of little blue wire-nuts!
They were going on 45 years when I discovered them under the stage at a church. Gray foil-shield Belden multiplier. No problems with them, the stage was just getting torn out and rebuilt bigger.

But seriously, phoenix/euroblock type connector plugs make great junction devices. I have bins of unused ones from things that have logic connectors or stuff that isn't used in most of my installs. You twist the little wires together first, then put that into the connector and crank it down. You don't actually have to plug the connector into anything.
Makes me wish for an affordable inline one with screw downs on each end of it (I've searched their huge catalog to no avail. -bonus points if it is din-rail mounted)

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