Tune your double bass (contrabass) instantly with professional accuracy! Perfect for orchestra, jazz, classical, and studio musicians. • Displays exact pitch frequency in Hz • A4 temperaments from 392Hz–466Hz • Includes tuning fork & advanced settings (IAP) • Exceptional sensitivity for low-frequency instruments • LED tuning indicator for intuitive visual feedback • Tuned string lights up automatically • Universal app for iPhone & iPad Allow microphone access: Settings > Privacy > Microphone. Questions? [email protected]