Electronic foot pedal controls for musical instrument amplifiers; speakers, namely, audio speakers; speaker cables, namely, electric audio speaker cables and audio cables; electronic effects loop interface units for musical instrument amplifiers; electronic effects pedals for use with musical instruments; audio speaker cabinets and protective covers therefor; musical instrument amplifiers and protective covers therefor; electrical cables for musical instruments; software plugins, namely, downloadable software for emulating the sound characteristics and sound samples of musical instrument amplifiers for use in digital reproduction, production, editing and mixing of music and other audio data; electronic effects pedals for use with musical instruments; musical instrument amplifiers.