The SPL Crescendo Duo is a two-channel preamplifier meant for recording audio at extremely high qualities. Though intended for the tracking and recording stage, the Crescendo Duo utilizes the 120V Rail technology SPL normally reserves for their mastering-grade gear.
 
The 120V rail technology allows for capturing more dynamic range with a greater headroom than you'd typically find in recording gear. Thus, you can use this preamp to capture the most dynamic material you'd come across, such as recordings for jazz and classical music, where compression is usually undesirable at the recording stage.
 
Another interesting feature is the parallel output section. Yes, this is a two channel preamp, able to record dual-miked sources such as drum overheads, pianos, acoustic guitars, and the like; however, each input offers two parallel, mirrored outputs, so you can route sound to two different destinations. If you're in a mission-critical scenario, you can use this feature to route audio to a backup recording system, thus obviating technical difficulties should the primary system fail. Great care has gone into the componentry that splits the output signals, so you can expect no loss in fidelity.
 
The unit offers balanced XLR connections, as well as controls over phantom power, polarity, and a built-in high-pass filter. You'll also note the prominent gain dial, -20 dB pad, output attenuator, and meter trim for particularly hot signals. A power cord is included.