Trying to record a few bits and I'm getting hum coming through both channels (Direct Output - Git Studio, Monitor Output - Stack). It is much worse on the Direct Output channel. I know the main cause is the guitar because if I plug my acoustic in it is much less but I thought the ground lift would take care of that?
Hum present even with ground lift
- tubelube
- Thread is marked as Resolved.
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Ground lift is used to remove hum from ground loop induced hum. Ground loop, in simple terms is from connecting two grounded pieces of equipment together, i.e. in a loop, but they have different potentials. I.E some extraneous current is flowing between them. Lifting the ground on one, breaks that loop, and thus the noise.
However your hum is from your single coils, not from a ground loop. The ground lift would help, when profiling an amp for instance, where you have the two connected together, KPA and Amp X. That is, assuming they created a ground loop.
You need to use techniques for reducing hum in your guitar, (again assuming single coils, P90s, etc.). Shield the guitar better. Remove hum inducers in single coils from the environment (old school fluorescents, ceiling fans, computers near, etc, look at the EHX Hum Debugger, etc.
Is it a single coil guitar? Strat? Try in positions 2 and 4. Should be hum cancelling in those. P90 guitar? Try the middle position.
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Hammerclaw humbuckers with a shield plate. Which one is in use makes no difference and where I stand in my room makes no difference.
Does touching the strings, bridge or tailpiece make a difference?
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It is either the guitar wiring or a problematic guitar cable.
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Yes. Touching the strings makes some difference but touching the bridge seems to be even better. Like I said I know it's the guitar because all I hear with my acoustic is the 50Hz hum (and it's very low). I just figured the ground lift on the kemper would sort it, guess I was wrong. Something not grounded in the guitar electrics?
It is either the guitar wiring or a problematic guitar cable.
Yep. Guitar and/or cable are not properly grounded.
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Tried continuity test with a multimeter from all strings, pots, pickups, the bridge and the ground on the output and they are all connected. I also tried with the audio output and there was no connections and I tried both of those with a lead in the output and the results were the same.... what's next I wonder?
Does the ground of the output jack have continuity with the ground of the pots?
If not, that is the connection that needs to be repaired.
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Tried continuity test with a multimeter from all strings, pots, pickups, the bridge and the ground on the output and they are all connected. I also tried with the audio output and there was no connections and I tried both of those with a lead in the output and the results were the same.... what's next I wonder?
If the hum goes away completely when you turn down the volume on the guitar then it's airborn interference that is being picked up by the pickups
Dimmer switches anywhere in the house can cause this (they can put an unholy amount of crap back onto the wiring). Fluorescent lights also - and I don't just mean strip lights but the individual energy saving bulbs based on that technology. I've had good results with the modern LED types though - no noise, better light and cheaper to run. Computers will do it too.
Your body acts like a big aerial for all this noise. When you touch the bridge, you earth yourself and the part of the noise you, the aerial, is causing goes to earth and is reduced hence the noise level coming down.
Also note that some profiles are noisy buggers...... Exclude that too
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If the hum goes away completely when you turn down the volume on the guitar then it's airborn interference that is being picked up by the pickups
Dimmer switches anywhere in the house can cause this (they can put an unholy amount of crap back onto the wiring). Fluorescent lights also - and I don't just mean strip lights but the individual energy saving bulbs based on that technology. I've had good results with the modern LED types though - no noise, better light and cheaper to run. Computers will do it too.Your body acts like a big aerial for all this noise. When you touch the bridge, you earth yourself and the part of the noise you, the aerial, is causing goes to earth and is reduced hence the noise level coming down.
Also note that some profiles are noisy buggers...... Exclude that too
It goes away, yes. Also putting the tone all the way down makes it go away. If I play a clean sound and pick the strings I can still hear it, even if my fingers are touching the strings. Strumming and I can't hear anything.
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Try touching the Green wire to the base of the pot. If that fixes the problem, great
If not, you can likely find an online schematic or pictoral diagram for exactly how the wiring should be on your guitar.
