Making a Humbuster Cable - 1 or 2 Conductor Cable Required?

stringrazor

Inspired
Pardon me if this question has been answered somewhere in this forum but my searches didn't find what I'm looking for.

I've seen the Wiki image on this topic and also comments saying all that's needed is to short the R&S on the TRS plug connected to the Axe/Fx 1/4" outputs. Can I simply put an R&S-shorted TRS plug on a single conductor shielded audio cable and have it work as a humbuster with my Axe/Fx II? It doesn't seem that I would actually need a 2-conductor cable if the 2nd conductor is shorted to the shield, unless I'm missing something...?
 
I presume humbuster uses both conductors to help cancel noise like a full balanced cable. So use the 2 conductor plus shield wire. The ring wire is soldered to the shield on the AMP side.
 
That doesn't sound right to me. I believe balanced cables are designed to reject noise picked up by the cable itself along its length. Each conductor as well as the shield is a discreet path, none are shorted together. One conductor carries the signal, one carries nothing. Any noise picked up by the cable will be picked up by both conductor wires equally. The noise rejection occurs when a circuit on the powered device side flips the phase of the neutral "noise" conductor and adds it to the signal of the hot conductor.

From what I've read, the humbuster function is designed to stop ground loop noise which is a different issue from noise picked up along a cable's length. Logically, if the ring and shield are shorted, they are electrically the same no matter on which end the physical short is made.

So, my question still stands....
 
The image clearly shows 2 conductors on both ends:

DC04CFBE-DF57-471C-9B89-82687C885B28.jpeg

I've highlighted one conductor in green on both ends and the other in yellow.
 
Yes but what would be the difference between that and this:

1568162607919.png

Wouldn't they be exactly the same to any device sensing from the TRS end? The R & S from the TRS end are connected to the S at the TS end in both, right? What purpose would the extra wire serve?
 
Yes but what would be the difference between that and this:

View attachment 58173

Wouldn't they be exactly the same to any device sensing from the TRS end? The R & S from the TRS end are connected to the S at the TS end in both, right? What purpose would the extra wire serve?
They would be exactly the same, if wires had zero impedance. But they don’t. In fact, if wires had zero impedance, there would be no such thing as ground loops.

Humbuster uses special electronics in Fractal outputs to sense how much noise is being induced into the cable. To do that, it needs that third conductor running the length of the cable. In your scheme, you’re shorting the ring and sleeve together at the Axe-FX end of the cable. That robs the Axe of the ability to sense the noise, and that would make Humbuster unable to do its job.
 
They would be exactly the same, if wires had zero impedance. But they don’t. In fact, if wires had zero impedance, there would be no such thing as ground loops.

Humbuster uses special electronics in Fractal outputs to sense how much noise is being induced into the cable. To do that, it needs that third conductor running the length of the cable. In your scheme, you’re shorting the ring and sleeve together at the Axe-FX end of the cable. That robs the Axe of the ability to sense the noise, and that would make Humbuster unable to do its job.

Thanks for that explanation.
 
Yes but what would be the difference between that and this:

View attachment 58173

Wouldn't they be exactly the same to any device sensing from the TRS end? The R & S from the TRS end are connected to the S at the TS end in both, right? What purpose would the extra wire serve?
Rex answered it... But even without that I would assume Fractal is smart enough to advise on the correct wiring compared to something (what you suggested) that would be much easier to create ;)

In other words, if your suggested wiring did work, they would have likely suggested that as it's an easier solution.
 
I made a couple of HB cables today and it worked out well. I was getting some hum and the new cables significantly reduced it.
 
I presume humbuster uses both conductors to help cancel noise like a full balanced cable. So use the 2 conductor plus shield wire. The ring wire is soldered to the shield on the AMP side.
So trying to make my own humbuster cable, think I missed a big step, can't use a regular guitar cable ? Need a mic cable ? 2 conductor would be 3 wires including the ground shielding, guitar cable is only 1 conductor and the ground shielding, correct ?
 
Yes but what would be the difference between that and this:

View attachment 58173

Wouldn't they be exactly the same to any device sensing from the TRS end? The R & S from the TRS end are connected to the S at the TS end in both, right? What purpose would the extra wire serve?
So trying to make my own humbuster cable, think I missed a big step, can't use a regular guitar cable ? Need a mic cable ? 2 conductor would be 3 wires including the ground shielding, guitar cable is only 1 conductor and the ground shielding, correct ?
 
Yes you need two conductor + sheild cables. Simplest way to make your own is to purchase a stereo/balanced 1/4" TRS to TRS cable and then short the ring and sleeve contacts together with a bit of wire inside the plug on one end of the cable. Mark that modified end of the cable with paint , tape, shrink wrap or whatever and always use that modified end on the opposite end from the Fractal device output (amp or stompbox's input).
 
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