Sonosax SX-M32 3-Channel Mixer
Sonosax SX-M32 3-Channel Mixer
Sonosax SX-M32 Front and Rear Panels
Sonosax SX-M32 Front and Rear Panels
Sonosax SX-M32 Left Panel
Sonosax SX-M32 Left Panel
Sonosax SX-M32 Right Panel without and with Option
Sonosax SX-M32 Right Panel without and with Option
Whether it is a trend in fashion, or a return to the origins, 3-channel mixers are thriving! Since the venerable SQN-3M Mono was released, the 3-channel mixer is by far the usual ENG and EFP mixer. The SX-M32 mixer is a direct competitor for the very sturdy Sound Devices 302 and for the Mixy (which comes from another planet). It is a classic mixer, with quality preamps, and many features rarely available on a mixer of this size.

Providing three balanced inputs for two main outputs, the SX-M32 Sonosax is smaller-sized, 6.93" x 1.75" x 5.43", and weighs 1.98 lbs with batteries. On this ground, it competes with other mixers, even though it may at first seem more fragile.

Sonosax at last follows mixer and recorder conventional settings, established by the Nagra III as an axiom: inputs on the left side, output on the right side, powering on the back, main commands on the front. These SX-M32 settings could be optimal except for some details that somewhat spoil this proven principle.

The hood on the back of the device provides access to a 6 AA-battery compartment. As batteries are not firmly kept in their container, they can easily fall if you take out this container upside down. Six AA batteries provide no more than three hours autonomy (instead of five hours, as announced) which is quite low for an ENG mixer. The adaptable and generous, SX-M32 can be 6 to 18 V powered on a Hirose connector, which is set just above the audio inputs, and so hindering access! The problem being that the SX-M32 does not provide any measure of remaining external capacity, which is yet major information.

Were it not for the awkward orientation of the three XLR input connectors, the left panel of the SX-M32 would be perfect. Set this way, with a 90° rotation from normal, unplug input 1 and 2 is difficult with lumberjack hands! These three mic/line 2.5 kilo-ohms impedance inputs are transformer-less, electronically balanced, and equipped with a RF filter. Under each of these inputs are four mini switches, well protected but rather hard to handle with gloves: 48 V Phantom power, LF Cut (passive 6 dB/octave at 130 Hz), Pad (-20 dB) and phase reversal. The activation of these switches is in down position, logically toward labels and not toward inputs. An auxiliary asymmetric stereo bus input, with mini XLR TA3 connector, lets you connect any external audio device directly on the mix busses L & R, at line level without any adjustment, for example another mixer to build a six channels mixer.

Outputs, all grouped on the right side panel, provide different interconnecting solutions. Besides the main XLR left-right outputs, electronically balanced, transformer-less (+6 dBu level), the SX-M32 provides an asymmetric stereo output which can be connected for example to a mini backup recorder, and an unbalanced mono output, handy for a monitoring system, for example. These two mini XLR TA3 outputs are next to a 1/4" jack headphone output, which is doubled on front panel by a mini jack output. Once again, 90° setting of XLR connectors would facilitate output unplug, which can be done only by unplugging, in this order, headphone jack, left connector, then right connector! Let's also note that there is no engraved label to show where are left and right outputs, an unfortunate oversight!

A digital output with TA3 connector, provides an impressive 119 dB dynamic, thanks to a high quality converter. Unfortunately sampling and format choice is poor and internally set.

One could blame Sonosax TA3 connectors for not having a lock, which is not safe on a hectic shoot, with a classic bag.

Finally, an optional custom multi-use connector allows, after fitting by qualified personal, for either direct outputs (mainly for use with a recorder such as the 744T), or several monitor return to suit all types of cameras.

Cleverly, Sonosax has set on the right side panel, an unbalanced stereo monitoring input, with TA3 connector, and -20 to +6 dBu adjustable level. This exception is necessary to easily connect a monitor return cable to a camera or to any other remote recorder.

The front panel provides controls for the three channels, the monitoring section and meters. Sonosax was obviously inspired by the Sound Devices mixers, for the SX-M32 front panel. Indeed we find the triplet configuration which has made the good ergonomics reputation of Sound Devices mixers. For each input channel we find a modulation potentiometer, a gain potentiometer and a potentiometer for adjusting the progressive active low cut filter, the last two are retractable. Sonosax adds an input level display with three yellow, green, red LEDs. These LEDs combine to show saturation and limiter activation. A pan LCR switch sends channel output signal to the main output, left, right, or both.

Channel's fader 1 can be linked with channel's fader 2 by means of a three-position LINK / MS selector. When the low cut filter retractable knob is released (in upward position), pre-fader listening function (PFL) of the channel is activated, and input level is displayed on the main modulometer. Each input channel has a limiter, unfortunately not adjustable and rather high calibrated -2 dB before saturation.

There is no level adjustment on the main outputs. Each summer has a limiter, located before the analog outputs and before the analog/digital converter. To limit the amplitude of a stereo signal, one should use LINK position to maintain stereo balance. The SX-M32 is provided with a slate mic in the upper right corner on the front panel, and with an oscillator for calibration. Finally the three-position power switch has a power saving mode for modulometer display.

The monitoring switch is classic, with the possibility to listen to a MS signal decoded, then summed in mono. Some will regret that the position adjacent to Mono is the right channel instead of the left channel.

The modulometers are clearly visible; they are factory programmed to behave as Peak Meters. According to cameras or recorders, modulation will be around +6 dB Vu. In that case, it would be easier if the three 1 to +6 diodes were orange, and the three next were red.

The sound of the SX-M32 Sonosax is up to the reputation of its manufacturer. Very analytical, bass is neat, spectrum balance is mastered with astonishing clarity, dynamic is excellent, the large gain allows capture of the more subtle sounds, with a remarkable absence of noise, this mixer is ideal for modern microphones such as the Schoeps CMIT 5 or Sennheiser 8000 series. Some, on the contrary, may criticize it for its analytical side, which will uneasily fit the roundness of the old Neumann KM 84, USM 69, U 87 or even KM 100 series.

In conclusion, despite some flaws and the rigidity of its design (because of the lack of setup menu, everything must be done at workshop), the SX-M32 can be used both on broadcast shoots and on film shoots, even in difficult working conditions, thanks to a smart manufacturing, such as retractable potentiometers, low-cut filters on two layers, significant sound quality and advanced ergonomics.

Come visit DC Audiovisuel and try it out; form your own opinion, by comparing it with other mixers on the market. The Sonosax SX-M32 is worth spending your money in the Little Swizterland.
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