Sonoflex is a flexible, textile dynamic speaker made without using a permanent magnet. Our design consists of two flat spiral coils, stacked on top of each other, and is based on an isolated, thin enameled copper wire. Our approach allows for thin, lightweight, and flexible embroidered devices and does not require high voltage as in electrostatic speakers. We show how Sonoflex can be designed and fabricated, and evaluate its acoustic properties with respect to manufacturing parameters, such as size, turn counts, turn spacing, and substrate materials. We are able to produce audible sound with a broad frequency range of 1.5 kHz – 20 kHz with a 50 mm diameter implementation.