There have been many occasions over the past few years when readers of the magazine have telephoned me and asked if I knew of a simple line mixer with lots of inputs that would be suitable for basic keyboard submixing. It seems reasonable enough to expect such a product to be available, but the reality is that most of the rack mixers on offer are unnecessarily complicated — for example, products like the Mackie LM3204 and the Studiomaster 162BP (reviewed in SOS March 1995 and July 2001 respectively) have full channel EQ and multiple auxiliary sends, as well as taking up lots of rack space.
The Rolls RM203X reviewed in SOS January 2003 provided one answer to this problem, but now our friends at Behringer have joined the fray by adding the RX1602 to their Eurorack Pro range. This 1U rackmount mixer is a simple but clean way to submix hardware synths to a single stereo feed that can be returned to a pair of inputs on a computer's audio interface.
Despite having the word 'Pro' in the title — which in the context of audio equipment is usually as good as an admission that it isn't (when did you last see a Neve preamp or SSL console with Pro written on the front panel?) — the RX1602 offers good-quality basic line-level mixing in a mains-powered unit.
The reason that a mixer can be reviewed in such a short space as this is that the Behringer RX1602 has very few features. All the connections are on the rear panel, where you'll find 16 balanced TRS jack line inputs arranged as eight stereo pairs, two main outs on TRS jacks (these are specified as being unbalanced, even though they are on TRS jacks), and a single aux send buss.
The aux send is normally configured as post-mute, pre-fader, but you can modify the circuit board very easily (at the expense of voiding the warranty) to change this to a post-fade send on a per-channel basis — the manual tells you exactly how to do this by cutting one link and adding another. A switch on each channel allows the input sensitivity to be switched from -10dBV to +4dBu.
On the front panel are eight identical sets of stereo channel controls comprising Level (up to 15dB of gain), Balance, and Mon/FX (the aux send), all on rotary pots. An illuminated channel Mute button also doubles as a clip warning LED. In the master section there's a headphone outlet with its own Level control, a pair of master Level controls for the left and right outputs, and a further Mon/FX master control with a button that enables you to monitor the send buss via the headphone output. Stereo eight-section LED meters monitor the output level, and a large square power button resides at the right-hand end of the panel.
The RX1602 is a nice-looking and seemingly solid piece of equipment, even though it is very inexpensive, and the only flaw I can find is that the outputs are unbalanced, which means that you may need to make up a pair of unbalanced-to-balanced ground-lift cables to avoid ground-loop hum in some systems. The mixer is certainly very quiet, has plenty of headroom (with a maximum output capability of +22dB), and boasts a frequency response covering 20Hz-20kHz ±0.2dB, which is only 3dB down at 200kHz.
As a solution to my synth submixing problem, the RX1602 came close to being ideal, but it would also work well as an aux returns expander on a larger console, and could even be pressed into service as a live sound keyboard mixer, provided that you don't need EQ. It could also be used in a computer-based studio to provide multiple feeds to a monitor controller such as a Samson C*Control or Mackie Big Knob, allowing you to play keyboards, guitar preamps, CD players and so on through the monitor system at the same time without your computer having to be switched on.
While the RX1602 has no effects returns, EQ, PFL buttons, or any of the other more advanced facilities available on a large console, it offers a compact and effective way to mix up to eight stereo line-level sources, and it does so very well. I now have one as part of my own studio system, and I'm sure many other musicians will find that it meets a need, both live and in the studio.