Like all of Apogee’s products, the Symphony I/O is a Mac-only device. Although this limits Apogee’s market, it also means that its devices are very well integrated with Apple’s hardware and the Mac OS X operating system. Perhaps the Symphony’s most unique feature when compared to the HD OMNI, however, is its modular design. It includes two I/O module slots into which any two of eight separately available I/O modules can be inserted. Each module includes a specific series of inputs and outputs covering the needs of most studios, making the Symphony I/O extremely versatile.
Unlike the Symphony I/O, the HD OMNI works across platforms, operating equally well under Windows and Mac OS X. Although it works with any digital audio workstation, such as Apple’s Logic or Ableton Live, the HD OMNI is optimized to work with Avid’s Pro Tools. The HD OMNI also includes a large variety of inputs and outputs adaptable to nearly any small studio scenario. In fact, depending on your studio’s needs, the HD OMNI may offer more of the kinds of inputs you need than any one combination of Symphony I/O modules can offer.
Both devices can handle not only multiple digital inputs, but multiple analog inputs as well. Both also offer comparable frequency response ranges for the different input types and both can interface with a variety of ADAT and other digital or analog recording devices. An important common feature is word clock functionality, meaning either device can be used as a studio master to control the timing of compatible equipment.
The HD OMNI’s price of between $2,500 and $3,000 USD, as of November 2011, is almost twice that of the Symphony I/O base unit, depending on where you buy. However, each Symphony I/O module costs nearly $2,000 USD apiece, making the Symphony I/O a much more expensive prospect if you require multiple modules to cover your needs. In essence, the HD OMNI is a good all-around audio interface with sufficient inputs and outputs for most small studios, particularly those running Avid’s Pro Tools. The Symphony I/O, by contrast, offers much greater versatility to Mac-based musicians, but at a proportionately higher price.