other flexibility, gave DAT many advantages over PCM adaptor-based systems. Digital recorders capable of multi-track recording such as Mitsubishi's ProDigi format and Sony's DASH format also became available on the professional audio market about the same time as the introduction of PCM adaptors. Other tape-based digital audio recording systems overcame problems that made typical analog recorders unable to meet the bandwidth (frequency range) demands of digital recording by a combination of higher tape speeds, narrower head gaps used in combination with metal-formulation tapes, and the spreading of data across multiple parallel tracks. Despite obsolescence, hobbyists are still capable of using modern-day DVDs or Blu-ray discs as a transport medium for video-based encoding of digital audio streams. Notes References Audio storage Video storage Digital audio Japanese inventions