small and lightweight battery, amp & speaker

Floris

What would be your suggestions for a battery, amplifier and loudspeaker that keep my Bela project as lightweight, small and flat as possible?

I just tested with a 7,5cm speaker and the build in amp from the original Bela and the sound was fine.
But the sepaker is just too bulky and heavy. The final project will use a Bela Gem, that's smaller but lacks the amplifier.
I was using a 0,3kg power bank which worked well but could be lighter. I don't mind building batteries, but would need recommendations.

giuliomoro

For a battery, you may want to use lipo cell, these come in all sort of sizes.

To get estimated battery duration, get the battery's advertised mAh and divide it by 1000 times the value from the table above for the use case you are targeting (most likely audio + 1 core load).

Speaker amps, see what adafruit and sparkfun have, keeping in mind that having an option for differential input may be better than having single ended inputs. Power amps may require larger voltages than provided by single-cell lipos, so you either need a dedicated battery for those or a power booster. If possible, avoid sharing the power between Gem and the power amp, unless the power amp has a differential input.

For speakers, I don't have any specific recommendations as it really depend on size and power needed.