Giving Jambu Better Ears

Sitting still on a desk, a basic USB microphone is good enough to hear a clear “Jambu.” On a robot — with its own motors, fans, and eventual road noise — it isn’t. So before floor-driving became a regular thing, the microphone got upgraded to a proper 4-mic array with onboard beamforming, echo cancellation, and noise suppression, paired with a small dedicated USB speaker instead of the old one.

New hardware, new gotchas. The array exposes two audio channels over USB, and it turned out the “first” one was the quiet one — the real signal, roughly 17 times louder, was on the second channel. Easy to miss, obvious once measured. The other adjustment was gain: the old microphone needed a software volume boost to hear anything useful; the new array has its own automatic gain control built in, so that same boost just clipped the signal. Turning it back down fixed it.

Small, unglamorous fixes — but this is most of what a hardware project like Jambu actually is. Not one big breakthrough, but a long chain of “why is this louder than expected” and “why is this the wrong channel,” solved one measurement at a time.