Why does my amplifier hum

You may not be able to completely get rid of unwanted noise but here are some things to take into consideration:. Why does my amplifier squeal when I play in my bedroom? The distance between your guitar pickups and your amplifier is responsible for the squealing noise you hear. The louder you set your amplifier, the greater this distance needs to be. If you plan to use your amplifier at higher volumes then move as far away from it as possible.

Unwanted Noise Why do I have unwanted sounds coming from my amp? Since I don't listen to music with my ear on my amp, it's not a problem. DC direct current cannot make the flux changes required to sustain a transferable magnetic field. Under normal conditions DC does not exist on power lines. However, because of nasty things like cheap lighting dimmer switches, sometimes a small DC component can occur on an AC line. Because toroidal cores are so efficient, they sustain magnetic flux easily.

DC offset on an AC line will eventually cause the toroidal core to go into saturation by continually driving the core into one direction. This sounds bad both literally and figuratively. I guess that's why my mono-blocks were so much louder than the A Ref, and probably why an old low wattage Adcom I have laying around isn't affected as much.

Hey, I've plugged just about everything I have to check out this problem. Foster 9, After 29 years, you have to have something to argue about. I guess if it weren't for my audio idiosyncricies, I'd be the perfect husband. LOL Jea48, I'm looking into an isolation transformer for that circuit. Something I can put safely in the attic.

The kitchen lights I was having problems with have the cheap electronic transformer built into in them. Rleff, Since the lights are on a different circuit, there would no difference in the AC voltage readings.

Even if I were to take AC V readings of that light circuit, I seriously doubt there would be much change off or on, since those lights have such a minimal amperage draw. Measuring AC and DC at the same time is beyond the abilities of my tester.

I think you would need a pretty sophisticated piece of equipment to be able to measure DC V leakage into an AC circuit. Heff48, DC offset caused by light dimmers, ceiling fan speed controllers, etc. Its one of the first things you look for as a possible cause when you have such hum problems. Heff48 I also have some sporadic hum, and have partially solved it with cheaters on Conrad Johnson preamp and keeping noisey lights off.

As a builder, perhaps you can advise me. I live in a modern condo but are stuck with 15 amp outlets. I am going to try to install a 20 amp home run this summer at great cost unfortunately for my audio gear.

Is there any kind of isolation transformer I could install to keep stray DC and other bad stuff out of my new circuit? Thanks Glenn. Prevention is better than cure. Avoid using electrical devices that are sources of DC offset in the first place. However, you have no control over what your neighbor on the same power company transformer does, and their use of such devices could affect you.

I have a similar humm problem from an unknown source. Danhirth Danhirth Danhirth, If you are hearing a hum through the speakers, jmho, the hum is not caused by DC offset voltage on the ac mains. The hum is more than likely a ground loop hum. The hum could also be caused by a bad electrolytic capacitor in the power supply of the amp or preamp.

You need to isolate the problem piece of equipment that is causing the hum. Start from the amp and add equipment upstream one at a time until the hum is heard. If the hum is heard through the speakers with only the amp, no ics connected, then the problem is the amp. Could be a dried out electrolytic cap in the power supply.

Danhirth, I'm curious, what setup did you use to obtain your DC offset readings? IMO 59mV is kinda low to cause hum problems. I cannot for the life of me imagine how these lights a make the power dirty, and b how that dirty power makies the transformer in my Emotiva XPA-5 emit what sounds like a 60 Hz. Firckin' amazing. Now- I wonder if there's a way to filter so the lights won't interfere Dirty power is only going to get worse due to the elimination of the incandescent light bulb.

Bad harmonics as well as DC offset. I wish this was the answer to my similar issue. Maybe I need to flip their breakers too! Hoff - your post was both entertaining and illuminating! I, too, have that mysterious, transient hum -- and now I know what to look for. I have found the source of my hum issues. I would like to add this post by Wayner, a member of Audio Circle. I too, was fighting a hum issue, thinking it was caused by dirty AC or poor interconnects or something else related to a ground loop.

The answer was distance. Having the amplifier checked and repaired by a qualified technician is the best way to solve this issue. Since there are many potential causes of hum, the first step is to determine the type of hum in your situation.

Experts have broken down hum into two wide categories: 60Hz hum caused by poor shielding, close proximity to magnetic fields, and cable problems; and Hz buzz, usually a result of ground loops.

To a wide extent, undesired amplifier noises are preventable and fixable when they occur. Matching speakers with an amplifier that can comfortably power them is the first line of defense against clipping. Not just any amp can power your speakers. These measures should help you to enjoy undistorted audio from your sound system consistently and for many years. Evanchuk owns an auto stereo center, where he offers highly competitive car audio installation and repair services.

He has written dozens of articles on different sound engineering topics, all of which have been published in leading journals, blogs, and websites. He enjoys swimming and boat riding during his leisure time.

Save my name, email, and website in this browser for the next time I comment. How can I get rid of clipping, hum, buzz and hiss from my amp? Amplifier Noises: Causes and how to detect and fix them. What is amplifier clipping and what causes it? You have a hunch: get a big, powerful amplifier and all clipping is kept at bay. Proper gain adjustment can eliminate a lot of amp clipping. Log in Social login does not work in incognito and private browsers. Please log in with your username or email to continue.

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Download Article Explore this Article methods. Tips and Warnings. Related Articles. Method 1. All rights reserved. This image may not be used by other entities without the express written consent of wikiHow, Inc. Lower the gain setting on your amp for the easiest solution. Turn off fluorescent lights and other interference sources in the room.

Fluorescent lights, Bluetooth devices, computer monitors, and dimmer switches all emit frequencies that create radio interference for amps. Leave your amp turned on while you shut off other devices in the room one by one. Listen carefully to the amp as you turn off each device to see if the hum disappears. Plug equipment into the same outlet to prevent ground-loop feedback.