Debugging a building for hum-buzz.

bri · April 5th, 2007, 09:07 PM

Anyone have any ideas about this? I play in our local Legion Hall at least once a week and the buzz in the wiring there drives my Nashville crazy. We have replaced a dimmer switch for the stage lights with a regular toggle and that seemed to help, but it's still unacceptable. The building isn't that huge so I'm thinking we could maybe put on a drive to find the other culprits. The only problem is that other than dimmer switches, I don't really know what to look for. Has anyone ever successfully done this? Are there tests you can perform to find faults? Any suggestions greatly appreciated. In desperation, I may try to go to noiseless pickups to keep from going insane. (see my post in the Just Pickup section concerning SCN pickups)
Brian

Tim Bowen · April 6th, 2007, 03:03 AM

There's the standard 60 cycle hum stuff, and then there's ground loops.

Some links to products that I have absolutely no experience with:

http://www.ebtechaudio.com/products.html
http://www.furmansound.com/product.php?div=01&id=PF-PRO

If you research upper echelon line conditioners and voltage regulators (I have), that particular Furman unit is quite inexpensive. You can spend thousands on the upscale units in a heartbeat. I've no idea whether it's worth it, as I simply can't pay the piper. David Gilmour can afford to hire Pete Cornish to design ultra-quiet rigs for him, but that's not within my budget either.

Not to be contrary, but if you were to troubleshoot and identify the culprit within the venue, what exactly would you do, in reality? You're not going to dig up the ground underneath the bandstand and place a copper grounding spike in the earth. And you're not going to ask to the venue manager to turn off the Budweiser and Miller Lite neon signs, as that's their advertising and ambience.

I work smoky bars and concert venues alike. For the most part, I don't encounter major noise issues. However, there's been a few rooms that I've worked over the years where I know in advance that there will be noise issues, and these are often located within old downtown districts. For these scenarios, I know, for example, that P-90 pickups are a non option.

For the average working player in the trenches (that's me, and perhaps yourself), the usual suspects apply: good cavity shielding within instruments, quality cables and connectors, a bit of common sense as to signal-to-noise ratio in designing a rig, doing whatever one can to ensure clean power (which, in reality, is very little, at least for those on a budget... for the most part, we're at the mercy of the house wiring).

Beyond that, it's noiseless pickups or some sort of noise suppression. As I'm sure you're aware, this subject has been bandied about many times, and I've participated in said discussions many times. I mostly play Fender guitars, and I like real single coil pickups. I dig the sound. So, I use a BOSS NS-2 noise suppressor. However, that's my personal preference as based on years of trial and error. It's not a universal solution or decree.

Best of luck, keep us posted.

chickenpicker · April 6th, 2007, 04:44 AM

Could you use your guitar as a tester? By that I mean go in when no one's around (so it's quiet), plug in and walk around. The hum should get louder in certain places (unless the building has serious wiring issues), so you'll see where the problems are.

Whether you'll be able to solve the problems is another matter, but here's an idea: Say you identify a source of hum, such as a dimmer switch. You could make an aluminium foil wrapped round cardboard baffle and place that in front of the dimmer. Then use crocodile clips and wire to connect the baffle to a ground point on your amp. It may look really stupid, but then again it might go unnoticed; and it might actually work.

April 5th, 2007, 09:07 PM	#1 (permalink)
bri Tele-Meister Join Date: Mar 2003 Location: Ontario, Canada Age: 68 Posts: 455	Debugging a building for hum-buzz. Anyone have any ideas about this? I play in our local Legion Hall at least once a week and the buzz in the wiring there drives my Nashville crazy. We have replaced a dimmer switch for the stage lights with a regular toggle and that seemed to help, but it's still unacceptable. The building isn't that huge so I'm thinking we could maybe put on a drive to find the other culprits. The only problem is that other than dimmer switches, I don't really know what to look for. Has anyone ever successfully done this? Are there tests you can perform to find faults? Any suggestions greatly appreciated. In desperation, I may try to go to noiseless pickups to keep from going insane. (see my post in the Just Pickup section concerning SCN pickups) Brian

April 6th, 2007, 03:03 AM	#2 (permalink)
Tim Bowen Friend of Leo's Join Date: Mar 2003 Location: Atlanta, Georgia Age: 48 Posts: 3,392	There's the standard 60 cycle hum stuff, and then there's ground loops. Some links to products that I have absolutely no experience with: http://www.ebtechaudio.com/products.html http://www.furmansound.com/product.php?div=01&id=PF-PRO If you research upper echelon line conditioners and voltage regulators (I have), that particular Furman unit is quite inexpensive. You can spend thousands on the upscale units in a heartbeat. I've no idea whether it's worth it, as I simply can't pay the piper. David Gilmour can afford to hire Pete Cornish to design ultra-quiet rigs for him, but that's not within my budget either. Not to be contrary, but if you were to troubleshoot and identify the culprit within the venue, what exactly would you do, in reality? You're not going to dig up the ground underneath the bandstand and place a copper grounding spike in the earth. And you're not going to ask to the venue manager to turn off the Budweiser and Miller Lite neon signs, as that's their advertising and ambience. I work smoky bars and concert venues alike. For the most part, I don't encounter major noise issues. However, there's been a few rooms that I've worked over the years where I know in advance that there will be noise issues, and these are often located within old downtown districts. For these scenarios, I know, for example, that P-90 pickups are a non option. For the average working player in the trenches (that's me, and perhaps yourself), the usual suspects apply: good cavity shielding within instruments, quality cables and connectors, a bit of common sense as to signal-to-noise ratio in designing a rig, doing whatever one can to ensure clean power (which, in reality, is very little, at least for those on a budget... for the most part, we're at the mercy of the house wiring). Beyond that, it's noiseless pickups or some sort of noise suppression. As I'm sure you're aware, this subject has been bandied about many times, and I've participated in said discussions many times. I mostly play Fender guitars, and I like real single coil pickups. I dig the sound. So, I use a BOSS NS-2 noise suppressor. However, that's my personal preference as based on years of trial and error. It's not a universal solution or decree. Best of luck, keep us posted. __________________ "Everyone is different in how they learn, but for me, it's turning the pegs and just playing." - BB

April 6th, 2007, 04:44 AM	#3 (permalink)
chickenpicker Friend of Leo's Join Date: Jan 2005 Location: UK Posts: 3,060 14 Photos	Could you use your guitar as a tester? By that I mean go in when no one's around (so it's quiet), plug in and walk around. The hum should get louder in certain places (unless the building has serious wiring issues), so you'll see where the problems are. Whether you'll be able to solve the problems is another matter, but here's an idea: Say you identify a source of hum, such as a dimmer switch. You could make an aluminium foil wrapped round cardboard baffle and place that in front of the dimmer. Then use crocodile clips and wire to connect the baffle to a ground point on your amp. It may look really stupid, but then again it might go unnoticed; and it might actually work.