Deliberately making a crackly cable

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Slothrop
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Deliberately making a crackly cable

Post by Slothrop » Wed Jul 10, 2019 10:02 am

Hi folks!

I like to play bass guitar in an FX-heavy ambient / noise / experimental sort of vein. As a child of the clicks-and-cuts era, I quite like the sound of crackly pots running through delay and reverb from time to time, but I don't really want to be stuck with something permanently knackered in the signal chain.

I can't find anything that does this off-the-shelf, so I'm kicking around the idea of trying to produce a deliberately crackly cable that I can plug it into the FX loop of a loop switcher pedal, so I can either make buzzes and crackles by fiddling with the cable or bypass it and have a solid signal chain.

For the cable, I'm basically expecting to split a short instrument cable, strip back the outer, reconnect the ground conductors properly (twisted together well with a blob of solder and then insulated) and then reconnecting the central hot conductor with a variably bad connection, eg loosely twisted together or attached via elastic bands to a piece of copper pipe or something.

Does this have a reasonable chance of a) doing what I want and b) not buggering up my gear in some way? Have I missed an obvious easier approach? I'm pretty much a novice at electronics, but I know which end of a soldering iron you hold, I have competent friends with the necessary kit, and none of this sounds too technically taxing...

Thanks!

proubaud

Post by proubaud » Wed Jul 10, 2019 11:54 am

Not answering your question, but god i love this forum :mrgreen:

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justin3am
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Post by justin3am » Wed Jul 10, 2019 12:12 pm

I made a cable like this. I used a little project box near the plug which connected to the instrument. Inside the project box I had a switch which acted like a pass though (on-off-on DPDT switch). It would pass signal normally in one position and in the other position ground and signal were just connected to a pair of terminals. I used alligator clips to connect the terminals through various components, or temporarily short the signal to ground or mimic an intermittent connection. It also worked well as a kill switch, when set to the off position.

It was just a one off, for a specific project I was working on. I'll have to see if I still have the cable in a bin somewhere.
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Noodle Twister
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Post by Noodle Twister » Wed Jul 10, 2019 2:36 pm

I had forgotten it's name but had a dig around and I think this https://bastl-instruments.com/eurorack/ ... el-kontakt

Could be just what your looking for.

Slothrop
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Post by Slothrop » Wed Jul 10, 2019 4:23 pm

Noodle Twister wrote:I had forgotten it's name but had a dig around and I think this https://bastl-instruments.com/eurorack/ ... el-kontakt

Could be just what your looking for.
Hah!
"It is also very usefull as a CABLE HANGER or as 1HP blank panel."
Although it's Eurorack format, whereas I'm after something more pedalboard-oriented. Also, as I read it they leave the sourcing of broken cables as an exercise for the user, which is kind of where my original question came in...

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Noodle Twister
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Post by Noodle Twister » Wed Jul 10, 2019 9:19 pm

It works with working cables too as it's the jack socket's that you deliberately break. Say's however to do this first whilst it's not in the rack (calibration haha) and then install to rack after.

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Post by danfan » Thu Jul 11, 2019 12:05 am

when i was an EAI-as-fuck young lad, i would take an end of an RCA cable and rub it on one of these coiled up in an aluminum tray from a little debbie thing:
https://images-na.ssl-images-amazon.com ... L1500_.jpg

with a lot of gain. loads of crackling. but also line hum.

maybe you can just make a 10x gain box in a pedal enclosure and have the switch just mute the signal path of the lead hooked up to it. that way you just stomp the pedal on and shake the cable/a contact mic/whatever around when you need to.

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JimY
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Post by JimY » Thu Jul 11, 2019 3:23 am

If you want the crackle to happen when the cable is moved - and not having to dedicate one or two hands to do it, then the wrong type of cable will.

Unscreened cable will be noisy, but also pick up hum and you may only want crackle.
The type of audio cable with a metal foil screen intended for fixed installations can be relied upon to crackle when moved, more so if in a high impedance input circuit like a guitar pedal.

Slothrop
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Post by Slothrop » Fri Jul 12, 2019 5:04 am

Ah, thanks - so as far as I can tell, you can actually find instrument and mic cables that are foil screened and generate handling noise, but it's hard to guess in advance which ones they are because they tend to be the sort of super-cheap ones that don't go in for pages and pages of tech specs. Otherwise I can find various things described as "foil screened twisted pair cable for fixed installation wiring" or suchlike - presumably getting a metre or so of that (edit: if I can find anywhere in the UK that sells it in less than 500m lengths...) and then attaching jack plugs would be the ticket?

In the short term, I'm tempted to just try taking a craft knife and cable strippers to a cheapo guitar cable - presumably the worst that's going to happen (unless I accidentally slice my fingers open or something) is that I trash the cable and don't get anything useful out of it?

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guest
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Post by guest » Fri Jul 12, 2019 5:16 pm

alternatively, you could use piezo wire:
https://www.mouser.com/ProductDetail/Me ... 3jDG4oE%3D

its a different sort of effect, but it would add handling noise for sure. not as much crackle, and you would have to add resistance in the cable so that any signals going through it didnt swamp out the piezo effect.
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chuckg
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Post by chuckg » Sat Jul 13, 2019 10:23 am

Now, why didn't I save all those crappy cables I've tossed away? Lost economic opportunity!
….working on it.

slow_riot
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Post by slow_riot » Sat Jul 13, 2019 10:27 am

DC offset into crappy pot, then remove the DC component (e.g. AC couple, subtraction).

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Pelsea
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Post by Pelsea » Sat Jul 13, 2019 11:37 am

Try some cable adaptors--1/4" to 3.5mm ->3.5mm to 1/4"-> repeat until you have a foot or so of them. Flexing the stack should give all the crackle you want. (Don't spend too much on the adapters.)
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ArboriaAuralist
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Post by ArboriaAuralist » Fri Jul 19, 2019 4:41 am

When I intentionally want a crackly cable I just loan out a good one for a day. :D

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