Creating a simple speaker on fabric and other materials was demonstrated by Hannah Perner-Wilson in this video. In the best version shown in her experiments, she places wide traces of conductive tape on canvas, and places the material over a rare-earth magnet.
Normal speakers operate by sending a signal through a "voice coil," that is suspended inside a permanent magnet. Force is exerted from the stable magnet to the free moving coil. And the signal through the coil changes it loves back and forth rapidly causing the air around it to pressurize. The pressurized air molecules propagate as a wave, and this is sound.
Speakers are quite inefficient, only able to convert 0.5 to 2% of the power into acoustic power. To make this simple The Power out is equal to the power in multiplied by efficiency.
Pout = hPin (h is efficiency)
So, with enough power, can my future speaker jacket bring the party?