Building on the original iRig, which essentially just provided a pre-amp for normalizing and filtering audio levels for analog input, the iRig HD adds a 24-bit analog-to-digital converter for passing true digital audio into the Dock Connector or Lightning port. iRig HD is designed to be used with IK Multimedia’s own AmpliTube family of guitar and effects processing apps, but also works with Apple’s GarageBand or any other real-time processing…