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ivanglam
12-10-2005, 08:48 PM
Usually, when I do my recordings, I either record electric guitar directly, or I go accoustic through a micophone. After my exposure to actual studio life and recording techniques, I learned that the proper way to record electric guitar is through an ampifier, and then into a microphone (because it gives better tone than straight into the computer via amp). But then I noticed something very weird. In there is a humming coming through my amplifier. Yes, I know that is common with many cheap amps, but mine is a 600$ amp.

My question to you is, what could be causing this 'white noise'?
Electrical power boxes?
TV's?
Closeness to computers/radios?

Any suggestions?


PS. this is the amp. (http://www.users.dialstart.net/~2metres/images/behringer-gx210.jpg)
(Behringer GX210)

sailorjim
12-11-2005, 12:11 AM
I also have a Berringer 212. It also has white noise., only when the front pick up on the guitar is selected or the rear pick up but not both. I thought it was the guitar, it was a peavy raptor cheap tele knock off. However I just got a Schecter Classic and it does the same thing..

magicninja
12-11-2005, 01:27 AM
My question to you is, what could be causing this 'white noise'?
Electrical power boxes?
TV's?
Closeness to computers/radios?


Yes, yes, and yes. Also, flourescent lights, bad grounds anywhere in the loop, the electrical setup of your house ( a power conditioner takes care of this one), too many things too mention. Best thing is to use a noise reduction pre and post.

Grambo
12-11-2005, 01:31 AM
yes: checkout, Amp to PC, on this page

Akira
12-11-2005, 05:28 AM
I'd try moving your amp around the room that it's in, or moving yourself around the room.

Andrew Sa
12-11-2005, 05:56 AM
It could be caused by any of those and many many other problems...

I have an electric fence around my house and that gives me numerous problems when recording through my amp..(oh, thank heavens for my Pod).

Fenderalltheway
12-11-2005, 12:47 PM
ya i have that to...but i dont really mind it...too much

ivanglam
12-11-2005, 07:18 PM
I find the noise is on regardless of normal volume, although increases when master volume is increased. Any suggestions to rid myself of this, or is this purley the amp?

ivanglam
12-11-2005, 07:20 PM
none of that really helps :( . I do find though that the noise increases only with the master volume. The noise remains constant regarless of regular volume.

Lordathestrings
12-11-2005, 08:49 PM
none of that really helps :( . I do find though that the noise increases only with the master volume. The noise remains constant regarless of regular volume.

That indicates that the noise is not being fed to the amp input from an external source. :)

Of course, it also indicates that the noise is originating in the power stage of your amp. :(

Superhuman
12-12-2005, 08:30 AM
Try turning off your pc monitor, the photons spilling out of the screen will cause interference through the pickups. Also, make sure that any audio cables are not crossing power cables and that your amp is not too close to a large power supply (eg extension plugs with power convertors etc). Try setting up the amp and gear as far from the pc as possible and sitting as far away from both as you can. Hum on the amp can be reduced through phase invertion in your software package (if it can't be reduced by any other means). Hope this helps.

Lordathestrings
12-12-2005, 10:50 PM
... the photons spilling out of the screen will cause interference through the pickups. ...

wtf? :confused:

Superhuman
12-14-2005, 07:58 AM
wtf? :confused:

Photons from the screen of a regular monitor (not TFT screen) cause major hum and interference on electric guitars, its amplified then if you are using a distorted channel. Check out the following link for more info on reducing electrical interference:

http://www.soundonsound.com/sos/1995_articles/apr95/homestudio2.html

Lordathestrings
12-14-2005, 05:20 PM
Photons from the screen of a regular monitor (not TFT screen) cause major hum and interference on electric guitars....

Not bloody likely! Photons are the minimum quanta of light, used by theoretical physicists to explain why light sometimes behaves like it's made up of particles.

I run a test lab that assesses electronic equipment for the level of interference it causes, or that it can tolerate. Photon emission does not cause hum! The electrical and magnetic noise generated by monitors and fluorescent tubes can definitely create havoc, but the light is no problem at all.

Superhuman
12-15-2005, 11:26 AM
That's good to know. I read about photon interference in a few recording articles... they all seemed to blame the interference from boxy monitor screens as coming from photon emissions... so does it actually come from the magnetic field generated by the equipment or something else? Just wondering because even though I have a TFT screen I get interference if I face my pickups towards it. I'm using Dimarzio Breeds and they seem to be the most sensitive pickups I have owned to date, they pick up noise from everything in the room and even pick up pops and crackles if someone turns on a light in another room in the house...

Lordathestrings
12-15-2005, 12:19 PM
Some background:

I work in a technical field called >EMC (http://www.etc-mpb.com/)< (ElectroMagnetic Compatibility). This breaks down into two courses of investigation: Emissions, and Immunity.

For emissions testing, we put the test sample in an electrically 'quiet' room, and listen to it with sensitive antennas and analyzing equipment. If it makes more noise than the applicable regulations permit, the product can not be sold in the marketplace.

Immunity testing subjects a product sample to specified levels of interference to see if it will continue to operate as specified by the manufacturer. Again, if it fails, it can't be sold commercially.

These tests weed out the worst offenders, but since a certain amount of noise is allowed, there is always the potential for two pieces of equipment to interfere with each other.

Any time you get a current flowing through a wire, there is a magnetic field produced around that wire. If the amplitude of current changes, the amplitude of the magnetic field will change with it. A changing magnetic field will induce a current in any wire that is in the field. This is how guitar pickups work.

Electric fields are the result of voltages appearing between two points, instead of current flow, but they behave somewhat like magnetic fields, and they can also effect electronic devices.


So, in a computer monitor you have voltages being switched at high frequecy, and current flow being started and stopped at high frequency. Older picture-tube monitors are worse because they use high voltages (reulting in high currents), but even new LCD and plasma displays give off emissions. Both magnetic and electric-field. Same thing with fluorescent lights.

These emissions can get picked up by anything that acts like an antenna. Which means that your pickups do a great job of receiving magnetic pulses, and cables can be very good E-field antennas. And then the amplifiers boost these interference signals along with the music. Articles like that SoundOnSound link give some ideas of what problems are likely to occur and some solutions to try when they do.