Ground lift switch question

FPFL

FPFL

Experienced
Does having the ground switch in or out impact any sound or feel of playing?

Very related but not the same question - I was at a practice space with really bad noise problems and I had to gate the @#$% out of my 9 to be able to play. I hate to do that b/c it chokes off notes if you want sustain. I'm also looking at other things I can do to clean up the noise, like better power strips, etc. as I am stuck with this space for some time.
 
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@ FPFL,

You could also try the Furman AC-215A Surge Protector/Line Conditioner. Fits with a Temple Audio bracket securing the AC-215A to the underside of your TA board. Has 2 reliable 3-prong AC outlets that can power the FM9 and one additional device, preferably with a low-profile AC plug or power adapter. Dunlop makes some right-angle power adapters, just need to check amazon for them...

Amazon product ASIN B003PJ6NPO
I use mine with power switch always on, and my TA IEC Micro Power module for on/off. You'd need to do some surgery on a IEC power cable to thread the power cable up through the access port to the FM9, but here's how she looks:

YVwwl37.jpg
 
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FPFL said:
Does having the ground switch in or out impact any sound or feel of playing?
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I wouldn't expect it to.
FPFL said:
Very related but not the same question - I was at a practice space with really bad noise problems and I had to gate the @#$% out of my 9 to be able to play. I hate to do that b/c it chokes off notes if you want sustain. I'm also looking at other things I can do to clean up the noise, like better power strips, etc. as I am stuck with this space for some time.
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What kind of noise?

It could be from the power, or more likely from EMI, which can be challenging to eliminate in someone else's building.

Search for "EMI" here and you'll find plenty of suggestions on what you can do to try and solve it.
 
FPFL said:
Does having the ground switch in or out impact any sound or feel of playing?
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The ground-lift switch is only useful for dealing with ground loops, like 60-cycle hum, it won’t do anything for RFI that comes through the air and affects the guitar. It shouldn’t affect the sound or feel unless you’re fighting a ground loop, which is when it should help.

FPFL said:
Very related but not the same question - I was at a practice space with really bad noise problems and I had to gate the @#$% out of my 9 to be able to play. I hate to do that b/c it chokes off notes if you want sustain. I'm also looking at other things I can do to clean up the noise, like better power strips, etc. as I am stuck with this space for some time.
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“really bad noise” doesn’t really tell us what kind of noise it was, but if it was able to be improved by the noise gate it sounds like it was RFI, noise from something else being picked up by the guitar. If it would go away by turning off the guitar’s volume, or by turning in a circle to find a quieter orientation, then it was RFI.

Bad shielding in the guitar, broken/damaged shielding in the cable, bad cables or shielding cables to, between, or from external pedals in an effects loop, electrical motors or circuits, different types of lights, cell phones and WiFi routers can cause it. And it’s a lot harder to fix.
 
unix-guy said:
I wouldn't expect it to.

What kind of noise?

It could be from the power, or more likely from EMI, which can be challenging to eliminate in someone else's building.

Search for "EMI" here and you'll find plenty of suggestions on what you can do to try and solve it.
Click to expand...
If I were ever troubleshooting EMI, first thing to do is check lighting. Any fluorescent bulbs? Swap 'em for LEDs. Any sensitive electronic equipment close to your music room or workstation? Be sure your computer, video and audio gear utilize separate circuit breaker circuits, or are connected to reliable UPS power supplies, or surge protector/line conditoners.

Case in point, my video gear is plugged into one UPS unit, and my computer is connected to a separate UPS. My computer monitors are powered via power strip-switchable wall outlet, my FRFRs and audio peripherals, as well as my printer, are powered via reliable surge protection/line conditioners, and lastly, my FM9 is powered via a Furman AC-215A surge/conditioner unit into a wall outlet. The video gear resides on the opposite side of the room, whereas the computer, printer, and audio gear the same side of the room, into 3 separate wall outlets.

Sometimes you'll find that certain electronics components add to extraneous EMF/RFI (not exactly EMI, but close). I usually don't practice guitar with any video gear at the same time, because of the possibility of RFI. Since my computer monitors, drafting-style LED desk lamps and FM9 are on one circuit, that tends to isolate ambient line noise from these and doesn't affect either UPS or surge protectors.

If the OP owns his home and can afford it, I'd suggest he ask a licensed electrician to visit and evaluate his house wiring system. For perhaps 45 minutes work, the electrician might find if there are wiring issues that can be repaired that will help mitigate EMF/RFI in the affected rooms, or be able to offer simple solutions that the OP might not think of himself. If the owner rents, he might need apartment management's approval or ask management themselves to help solve his line noise issues. Something to consider is what type of guitar do you use, what pickups, etc.

Regards myself, my tendency is to look for the least invasive ways of handling a problem, instead of throwing money at it. Much the same way a doctor treats a patient, the diagnosis typically doesn't require the most expensive treatment. The doctor will typically prescribe something that will treat the issue for the least expense, instead of performing a costly surgery. If the doctor is doing his job correctly, he will also suggest preventive ways to avoid health issues.

Same goes for the electrician. If he can diagnose the problem, he also may be able to offer simple solutions instead of requiring costly repair. A trusted electrician will do this. But be aware of the guy who throws a huge number at you expecting you to agree to a costly repair. Find a trusted tech, just not the guy that your ex-girlfriend used for her recent apartment overhaul.
 
bleujazz3 said:
If I were ever troubleshooting EMI, first thing to do is check lighting. Any fluorescent bulbs? Swap 'em for LEDs. Any sensitive electronic equipment close to your music room or workstation? Be sure your computer, video and audio gear utilize separate circuit breaker circuits, or are connected to reliable UPS power supplies, or surge protector/line conditoners.

Case in point, my video gear is plugged into one UPS unit, and my computer is connected to a separate UPS. My computer monitors are powered via power strip-switchable wall outlet, my FRFRs and audio peripherals, as well as my printer, are powered via reliable surge protection/line conditioners, and lastly, my FM9 is powered via a Furman AC-215A surge/conditioner unit into a wall outlet. The video gear resides on the opposite side of the room, whereas the computer, printer, and audio gear the same side of the room, into 3 separate wall outlets.

Sometimes you'll find that certain electronics components add to extraneous EMF/RFI (not exactly EMI, but close). I usually don't practice guitar with any video gear at the same time, because of the possibility of RFI. Since my computer monitors, drafting-style LED desk lamps and FM9 are on one circuit, that tends to isolate ambient line noise from these and doesn't affect either UPS or surge protectors.

If the OP owns his home and can afford it, I'd suggest he ask a licensed electrician to visit and evaluate his house wiring system. For perhaps 45 minutes work, the electrician might find if there are wiring issues that can be repaired that will help mitigate EMF/RFI in the affected rooms, or be able to offer simple solutions that the OP might not think of himself. If the owner rents, he might need apartment management's approval or ask management themselves to help solve his line noise issues. Something to consider is what type of guitar do you use, what pickups, etc.

Regards myself, my tendency is to look for the least invasive ways of handling a problem, instead of throwing money at it. Much the same way a doctor treats a patient, the diagnosis typically doesn't require the most expensive treatment. The doctor will typically prescribe something that will treat the issue for the least expense, instead of performing a costly surgery. If the doctor is doing his job correctly, he will also suggest preventive ways to avoid health issues.

Same goes for the electrician. If he can diagnose the problem, he also may be able to offer simple solutions instead of requiring costly repair. A trusted electrician will do this. But be aware of the guy who throws a huge number at you expecting you to agree to a costly repair. Find a trusted tech, just not the guy that your ex-girlfriend used for her recent apartment overhaul.
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LED bulbs can also cause noise...

Also, if it is EMI, most likely there's not any wiring problem...

I wiring problem might lead to grounding issues that could cause other noise, though.
 
unix-guy said:
LED bulbs can also cause noise...

Also, if it is EMI, most likely there's not any wiring problem...

I wiring problem might lead to grounding issues that could cause other noise, though.
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Hmm. My 60W comparison LEDs are relatively silent, perhaps the quality and brand name of the bulb has something to do with it...methinks it's likely something unfriendly within the OP's circuits that is causing the problem. Anyway, gonna go sit with a cuppa tea and clean, warm socks, and a good book, and prep for a meeting. See you guys towards 10 PM.
 
Thanks folks. Appreciate the ideas and the humor!

Couple, three things...

This was not 60 cycle hum. Way squelchier and louder than that too.

Yes, this is a practice space, not my house - I can't do much work to the walls, power etc. At best I could swap out an outlet b/c they'd probably not notice, but that's it.

There are computers next room over, as it's a small, modern recording studio next door. The walls between us are unremarkable but they do have a lot of sound dampening up in their space.

Think of this as a "what would you do if you had little control over what was around you." situation. It's a workable space otherwise and it's something the band can afford so I'm going to try to make it work.

People pad the walls for sound dampening... I wonder what non-permanent things you can do for RFI in a rented space?
Could I make an RFI baffle of some sort up move it around me to see if there was directionality to where the problem was coming from?

I'm betting it's not a bad cable b/c I don't have anything like this with the same simple rig guitar -> FM9 -> power amp -> cab back at my house.

Be well!
 
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Dimmer switches can add a ton of noise. Most of them work by chopping up the 60 Hz AC waveform into a variable duty cycle waveform. This adds a bunch of harmonics to the waveform and can sound much worse than typical 60 cycle hum. If the space has ceiling fans, sometimes both the lights and the fan are wired through separate dimmers which makes it even worse.
 
Yes the noise can be so bad it overwhelms (effectively muting) everything else - including the band; I was being a bit cute and not 100% literal. It's well beyond a background hum or 'under the sound' as a lot noise is, this was the point I was making.
 
FPFL said:
Yes the noise can be so bad it overwhelms (effectively muting) everything else - including the band; I was being a bit cute and not 100% literal. It's well beyond a background hum or 'under the sound' as a lot noise is, this was the point I was making.
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If the interference is so loud that it overwhelms the audio, you pretty much have to locate the source and deal with it. Move your guitar all around the room at different angles. See where the interference is the loudest.

You say there are computers in the next room. Is there also a Wi-Fi router there? Those are notorious for generating interference.
 
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