Audio Troubleshooting Guide: Static, Hum and Bass
It’s something that we all do at least a few times in our lives – setting up a new stereo or home theater system. It’s one of those things that are much too expensive to outsource, but far enough outside the realms of our everyday life that problems often arise! Today we help you troubleshoot several common problems with new speaker setup, from speaker cable issues to power switches!
Why does my sound have static?
Static problems usually originate at the connection or speaker cable level. It is a simple process of elimination to find out which connection or cable is causing trouble:
- Check whether the static only occurs when the source is from one particular item. Does it only happen when watching DVDs? When listening to the stereo? When watching cable? This is a big clue as to what is causing it.
- If you get static no matter what you are listening to, check the cables and connections between the AVR (Audio Visual Receiver) and your amplifier
- If the static only comes from one speaker (or even if the previous tips fail to give you any hints), check the speaker cables and connections between the amplifier or the AVR itself and the speakers.
- If the static is still coming from all speakers and you have never had static-free listening, check that your speaker cables are the correct width for their length.
Why are my speakers humming?
Not quite the same as static, hum is more constant and less acutely annoying. It still has the potential to wreck your listening experience, though! Hum coming from your speakers is not usually a speaker cable issue, but to do with ground loops. These occur when two devices in a circuit or system are grounded through different paths. Noise voltage can occur with the difference between the two grounds.
You need to identify which appliances are running at a slightly different voltage – look for a label on the appliance itself, or in the manufacturer’s information. A simple solution is to plug the two differently volted items into separate power sockets if possible. If this isn’t possible, an item called an isolation transformer can help.
What’s wrong with my bass?
I swear I used to have more bass than I do now – am I imagining things?
- There are several common reasons why your bass might have dropped out completely or become weak. Some people don’t realize that subwoofers have their own separate power switch, just like a television. Once you plug in the subwoofer speaker cable, you still need to switch the unit on to have it work. Check this first up, as the button can be easily bumped off even after it has been turned on.
- Also, your subwoofer needs its own power source as well as being connected by speaker cables to the stereo. If the power cable is loose, you won’t get bass.
- Another obvious one – just check the master volume level or control level on the back of the unit. They sometimes get ‘accidentally’ moved!
- Failing this, check in your AVR that the bass output is set to go to the subwoofer.
- If you have bass, but performance is an issue, set all of your speakers to ’small’ in your AVR with fixed global crossover of 80Hz. Defeat the low pass filter (LPF), or set it to its highest setting or you’ll get cascading effects.
- Check that the seating position is still optimal – if your furniture has moved, you may need to redo your auto-EQ calibration process.
