In recent years manufacturers introduced so-called "invisible sound" solutions. In-wall, surface mount or glass mount versions of different vibrating transducers are commercially available. The entire surface becomes a speaker delivering sound and the frequency response is said to be equivalent to conventional diaphragm speakers. Furthermore, the sound is omni directional at nearly all frequencies (60 Hz - 15 kHz) while channel separation is maintained. This paper presents measurement results of the SolidDrive SD1g transducer mounted on different glass surfaces, including vibration measurements and acoustic parameters. Furthermore, based on a numerical FEM-model using COMSOL, comparison between measured and simulated results and estimation of transfer function and directional characteristics are presented.