The 664 Six-Channel Portable Production Mixer with Integrated Recorder from Sound Devices has an unprecedented amount of functionality from a unit that can be battery operated. It starts with a low-noise, transformerless preamplifier section, continues to an intuitive mixing surface, adds a host of digitally-controlled routing features, allows room for analog inserts and aux busses, and finally terminates with versatile, plentiful output connectivity. By the way, the 664 can be configured to record digital audio to CompactFlash or an SD Card from any point in that signal flow.
The Sound Devices 664 has an input board that features six balanced XLR connections. Within the firmware, they can be selected to accept microphone or line level signals. Additionally, inputs 1 and 6 can configured to accept AES digital signals. Each channel has a direct output on an independent TA3 connector. There is also an input for a slate microphone, if you don't wish to use the 664's internal slate mic. Two headphone outputs are also provided.
The physical mixing surface of the 664 has the basic features you'd expect, such as trim pots, panning and level knobs. But it also has more advanced features, like sweepable high-pass filters and pre-fader listen switches on each channel.
The 664 has very flexible routing options within its LCD-based menu. When a channel's pre-fader listen switch is pushed to the right, it brings up that channel's menu options. Input level, pre/post track routing, aux buss routing, mix routing and polarity can all be adjusted. Channels can be paired in left/ride or mid/side modes. Phantom power can also be engaged at either 48V or 12V.
The Sound Devices 664 has many output options, from its balanced XLR main outputs to the unbalanced 1/8" stereo tape output. It can even send and receive word clock and timecode signals. Two Aux outputs on TA3 connectors allow custom track groups to be routed to external devices. The outputs can even be set to send AES digital signals of each buss and channel.
The 664 has an integrated recording system that tracks WAV files at up to 24-bit/48.048kHz resolution to CompactFlash or SD cards. The whole device can be powered by five AA batteries or an optional DC adapter.