Package includes TI-1b Transformer Interface.
Both packages include a one year manufacturer warranty. Headphone only package ships with just CA-1a Circumaural headphone, no cables or interface box included, Standard Package ships with the CA-1a Circumaural Ribbon Headphone and complete TI-1b package which includes:
OB Compensation barrel for Balanced XLR & Single-Ended RCA amplifier inputs
HPL Cable for connecting TI-1b to conventional 4-pin XLR headphone level amp output
SC2 Cable for connecting True-Ribbon™ headphones to TI-1b interface