Electrical and electronic audio apparatus; sound mixing, processing and synthesising apparatus; sound reinforcement systems; amplifiers; electrical amplifiers; electrical amplifiers for use with musical instruments; electro-acoustic amplifiers; power amplifiers for use in sound reproduction; sound amplifiers; valve amplifiers; tube amplifiers; valve amplifiers for sound amplification; solid-state amplifiers; solid-state amplifiers for sound amplification; hybrid amplifiers; hybrid amplifiers for sound amplification; combination amplifiers; head amplifiers; pre-amplifiers; public address systems; public address systems including passive enclosures; public address systems including powered enclosures; public address systems including mixer amplifiers; guitar amplifiers; acoustic guitar amplifiers; microphones, headphones; loudspeakers; mixing desks; audio mixing apparatus; audio mixing desks; mixing consoles; master audio mixing desks for use in an audio recording studio; loudspeaker cabinets, grilles and casings; switches and footswitches for use with amplifiers, musical instruments and sound reproduction equipment; sound and musical effects apparatus and equipment; electrical and electronic interfaces for use with musical instruments, amplifiers and loudspeakers; effects pedals; electrical leads, cables, plugs and connectors; batteries and power packs; chargers for batteries and power packs; USB interfaces; stands, bags and cases, all for use with loudspeakers and amplifiers; parts, fittings and accessories for all the aforesaid.;