Two scales for each fader. What is this?
Close observation of the input module will reveal two different scales printed on either side of the fader. One side has the "0" where you’d expect it – about ¾ up – with another 12dB to the top. But the other side has the "0" about halfway down the fader with 24dB to the top. What the hey?
Look again and notice a small two-position toggle switch to the left of the fader. One position is printed "12", and the other, "24". The "12" is considered the normal mode, but when switched to the "24" position the 24dB scale applies and there is an additional 12dB of gain available with the fader (a full 24dB above the "O" mark). In appropriate scenes, this allows you to set the input trim for the loudest yelling expected and still have plenty reach for the most delicate whispers – using only the fader – without having to touch the input trim when recording.
When I first saw this "+24dB" feature I had to wonder just how useful it would be in the real world. My first day on a commercial set with this mixer gave me the answer: The shot was a wide and high lock-off (the mic could only go so low and the ceiling prevented the mic from going any higher) of a couple lying in bed. The first lines were very soft while lying down. Then the couple would sit up suddenly and delivered much louder lines (closer to the mic), then lie back down and talk softly. Because of the yells at close proximity to the mic, I switched in the -10dB pad on the Sennheiser MKH-50, requiring even more gain for the whispers. Using the 24dB setting on the SX-ST I was able to record all of the lines at full scale, using only the fader and limiter to ride gain, all without input overload distortion or excessive noise. No other mixer I know of would have been able to do this. Now that Trew Audio has several SX-ST customers, reports from the field indicate that I’m not the only one who appreciates this unique feature.