Downloadable computer software applications for smartphones; computer software applications, downloadable; microphones; audio-and video-receivers; loudspeakers; megaphones; equalizers [audio apparatus]; wah-wah pedals; guitar effects processors; guitar amplifiers; electric and electronic effects units for musical instruments; pickup amplifiers; bluetooth earphones; wires, electric; electrical adapters; mobile power supply [rechargeable batteries]; battery chargers; dry cells.