Hums, buzzes, and hisses are just a few of the distracting and annoying electronic noises that plague audio and video systems. Noise can come from external systems or within a circuit itself.
In this article, you can learn proper and safe techniques on how to ground audio equipment.
Sources Of Electronic Noise
Electronic noise is an unwanted disturbance in an electric signal. The noise you hear in your audio equipment may be caused by many different natural or man-made factors.
Before we discuss the grounding techniques for your audio equipment, let’s have a quick look at what causes the noise.
External sources include:
- Power lines
- RF transmitters
- Ignition systems
- Nearby conductors and cables
- Motors that draw large electric currents
- Wireless systems
The noise produced by nearby conductors and cables is called electromagnetic interference or EMI. On the other hand, the noise caused by radiating signals from wireless systems is called radiofrequency interference or RFI.
The circuit itself can also generate noise because of faulty components and loose connections. Moreover, physical vibration and temperature increases in the environment can also cause noise.
In this article, we will focus on ground loops that are manifested as hums in your equipment. These loops occur when: multiple pieces of equipment are plugged into the AC at different locations and are connected by electrical signal cables whose shielding is connected to the ground.
Here are some tips to avoid a noisy electronic environment. You may ask for the assistance of an electrician or an electronics technician to apply some methods.
Some studios use star ground to prevent ground loops. In this scheme, every piece of gear has AC fault protection. However, no earth grounds are tied together.
This is a complex wiring scheme that requires a sufficient amount of time. If you wish to do this, you can ask for professional assistance. Here are the steps:
- Isolate each piece of gear from AC (alternating current) ground.
- Then, run a separate ground wire from the chassis of each gear back to the main studio ground.
- Connect the main studio ground back to a main AC ground, and/or a large copper rod that is driven 18 feet into the ground.
Plugging Into A Common Plug Group
Plug all your audio/video equipment into a single power strip or surge protector and plug it into the wall.
You may also try having your AC receptacles on dedicated lines. Wires of each AC receptacle should run back to a central breaker box.
If these methods still don’t eliminate the hum in your audio equipment, check your TV antenna or the cable-TV coax cable. These pieces of equipment may cause ground loops only if you are connecting directly to your TV or a video recorder. Disconnect the wire from the cable modem to check if the noise disappears. Replace it with ground-loop isolators. Know more about audio equipment here!
As mentioned in this article, there are many other sources of electronic noise. Consequently, there are many ways to address each. Here, you have learned ho how to ground audio equipment to prevent ground loops. Remember to seek professional advice and assistance when handling electronics to keep your equipment in good shape.