Voice Journey Lab

Follow a voice as it's chopped into packets, sent across the internet and rebuilt. Make the network worse and hear what happens to the call.

Codec: how the voice is squeezed

Network delayHow long a packet takes to cross the internet, one way.

JitterHow uneven the arrival times are. Some packets get stuck in traffic.

Packet lossPackets that never arrive at all.

Jitter bufferHow long Bob's phone waits before playing. Longer means fewer late packets, but more delay.

Hide gaps (packet loss concealment)The phone guesses missing pieces by repeating the last bit of sound.

Mouth-to-ear delay

0%lost on the way

0%arrived too late

80 kbpsper direction, with headers

50/spackets each way (one every 20 ms)

Listen and compare · 5 seconds of synthetic speech

lost packetarrived too late

Alice saysstraight from the microphone

Bob hearsafter codec + network

Click a waveform to play it. The voice is a synthetic “robot talker”, and the codec sound is an approximation of each codec's character. The quality score uses the ITU-T E-model (G.107); Opus values are estimates, since Opus isn't in the ITU tables.