Hall Research has released the AD-340 Universal Audio Delay Processor, which can add delay to stereo as well as multi-channel bitstream audio signals.
Audio delay has traditionally played an important role in large venue sound reinforcement systems, however the increasing prevalence of high definition video has created a new niche due to the time required to process HD video causing lip-sync issues. The AD-340 provides both analogue (L/R) and digital (SPDIF) inputs and outputs, enabling conversion between analog stereo to LPCM or vice versa.
Output delay can be dialed as milliseconds, video frames, or simply distance depending on the application. Analogue inputs provide +/- 24 db of gain for direct connection of low level mic as well as handling 2vrms line-level signals. The AD-340's digital I/O support 2-channel linear PCM, 5.1 Channel Dolby Digital, and DTS Surround encoded bitstreams at any sampling rate from 32KHz to 96KHz. Inputs are ground-loop isolated to prevent buzz and hum noise when connecting to PC's or other unbalanced sources.
For advanced control, the AD-340 connects to a PC via USB port. No special drivers are needed and Hall Research provides a free software utility that allows advanced features such as: selection of sample rate for analog inputs, temperature compensation of delay calculation for a given distance, and gain level control of analogue inputs and outputs.