BSM designed a new private stock booster just for the favorite taste of the company‘s mastermind. It was intended in first place to emulate the sound of the 1975 studio recording “Ritchie Blackmore’s Rainbow”, second to achieve Ritchie’s early Rainbow live sound that can be heard on the Nov. ’75 bootlegs, e.g. Bacon Theatre, NYC. Furthermore the unit was designed to get this sound from any stock “Bright” input found on classic Marshall amps.