PORTLAND, Ore.Studio-quality audio processing no longer requires expensive gear, according to Universal Audio Inc. (Scotts Valley, Calif.), which has harnessed up to four Analog Devices' Sharc (Super Harvard ARchitecture Computer) digital-signal processors on a single PCI Express board.
By plugging the Sharc-based board into even garden-variety PCs, all the audio processing capabilities of studio-grade gear become accessible to virtual mixers via software plug-ins.
"When you drop one of our plug-ins on a track, it looks like a piece of hardware with all the same controls knobs that people are already familiar with, but when you twist a [virtual] knob on the plug-in, it passes parameter changes down to the Sharc which does all the audio processing," said Brent Elder, vice president of engineering at Universal Audio.
For several years now, audio studio equipment makers have been using ADI's Sharc to transform their previously analog equipment into digital equivalents that use the DSP to emulate audio effects--including vintage analog equipment like Roland's "Space Echo" that has not be manufactured in years. With the introduction of Universal Audio's second-generation PCI Express cards, which can house one-, two- or four-Sharcs, now these same capabilities can be used even in home studios using virtual-mixer software running on a PC.
"Sharc has long been a top pick for pro audio applications, including those that bring the sound of vintage analog effects," said Denis Labrecque, DSP Marketing Programs Manager for Pro Audio at Analog Devices, Inc.
Software for virtual mixers, such as DigiDesign's ProTools, have required a high-end computer to make them work, since the computer's processor has to emulate analog functions at very high speeds in order to provide studio quality audio effects. However, offloading those functions into the Sharc-based PCI Express card, relieves the PC of responsibility for those tasks, enabling even garden-variety PCs to provide studio quality audio effects.
Universal Audio's PCI Express implementation realizes its goal by mediating between the virtual-mixer software and the DSPs, shuttling audio sample inputs from external devices into the Sharc, then back out to the audio outputs, using the PCI bus to accomplish all the input/output (I/O).
"All of our effects accelerators use Analog Devices' Sharc floating-point digital signal processor [DSP] on a PCI Express card that is tied together with a Xilinx FPGA [field programmable gate array] providing all the glue logic between the bus and the Sharc," saide Elder.
Universal Audio's Sharc-based PCI Express cards support sample rates up to 192 KHz, and are fast enough to emulate up 128 entire audio channels per Sharc--including volume, equalization, reverb and effects. PCI Express cards are offered with one-, two- or four-Sharcs, for up to 512 simultaneously real-time tracks.