How to Deal With Echo for VoIP

Echo is a problem anytime you want to have a conversation with someone. It's fun when you're by yourself and you want to play with the idea of your voice coming back to you with a measurable delay, but it's a nuisance when you have to deal with it during a phone conversation. Both you and your listener have to talk over your own voices.

Instructions

1. Recognize sidetone versus echo. Sidetone is your own voice that you hear when you talk to someone, whether in a face-to-face conversation or over the phone. Echo is characterized by a delay in hearing your words after you've spoken them.

2. Understand echo as not arising from VoIP systems themselves but from problems in the circuits which cause the outgoing voice to pop into the return path or from poor insulation in the handset which gives off the echo effect. A hybrid echo is created when the typical analog 2-wire interface meets a 4-wire interface somewhere along the path. An acoustic echo is produced when the mouthpiece is too close to the ear piece, allowing your outgoing voice to come back on the return path.

3. Install an ECAN (Echo Cancellation Device) at the receiving end of the call, which is where the echo problem originates. This device reads the incoming signal and eliminates an outgoing signal that exactly matches that pattern sound for sound. In this way, it sifts through the incoming voice and the outgoing voice to get rid of the echo effect. Distortion and anything else that changes the echo sound let it slip through the ECAN's ability to do anything about it.

4. Be aware that there is always some element of echo in any phone conversation of any type. VoIP systems are susceptible to it because of all the places in the system where delay occurs. This is about suppressing the echo rather than causing it not to occur.

5. Use a NetQoS VoIP unit to monitor every aspect of your calls. The device works well to monitor and suppress echo as it occurs by tracking levels of non-conversational noise and quashing them when they reach unacceptable levels.