Bose T1 ToneMatch Audio Engine and Mixer for the Bose L1 Audio System , Instrument & Vocal Tone Matching, 100 Proprietary ToneMatch Presets, Digital Multi Channel Mixer, Studio Grade Effects, Bose zEQ, Easy Connection to Bose L1 T1 Portable PA Systems T1 ToneMatch Audio Engine and Mixer for the Bose L1 Audio System