Top producer / engineer, George Shilling, also takes time out to review interesting audio equipmentGeorge Shilling reviews:

SSL X-Rack Mixer



I took a look at the SSL X-Rack a while back but back then the only module available was a Dynamics processor. In the meantime, SSL have introduced a series of modules which enable the user to configure a custom system, much like any other lunchbox or powered rack system – e.g. the API 500 series.

The configuration sent for review brings together some predictable additions to the X-Rack range, plus modules which enable configuration as a mini-mixer. Unsurprising add-ons, derived directly from SSL’s large analogue consoles, are a mono Input module with mic, line and DI inputs, plus filters, and also an EQ module, with familiar four band E/G Series EQ. The mixer module is a four input Line Return unit; this is designed to work in conjunction with the new Master module, the latter’s features resembling a desk’s centre section.


All modules utilise the Total Recall system using LEDs in the module panels, as detailed in the previous review. Knobs have a tiny LED to indicate above/below positions. This is something no rival can boast, being as it is self-contained, with the option of storage in a DAW via MIDI. Unlike SSL consoles and newer AMS-Neve outboard, there are no onscreen graphics to watch. Because one’s eye is always on the unit, there is therefore less chance of turning the wrong knob. It is a very neat system, but there was some audio interference on the main Master monitor outputs when in Recall mode - a continuous burbling hum.


One initial drawback of the Line Return and Master modules is that their compact size necessitates the employment of 25-pin D-Sub connectors. This wouldn’t be such a problem, but SSL make things marginally worse by employing non-standard wiring formats for these. This is partly necessary due to the unique combination of inputs and outputs required, but it does seem odd that they have used reversed polarity for the pin wiring compared to the more commonly adopted Tascam standard. Custom cabling will be required!


The comprehensively featured Input module includes a neutral and quiet SuperAnalogue microphone preamp, with excellent transient handling and clarity, and plenty of gain. An Impedance knob allows wide variation of the mic input, even matching the connection of Line sources, although there is a dedicated Line input section with separate XLR input and gain knob. The Instrument input jack on the front panel includes a useful Ground Lift switch, and this input sounds particularly solid on bass guitar. A tri-colour LED senses level prior to the output amplifier, and there are useful routing buttons to select Left and/or Right Record Buss on the Master module (see below). Smooth sounding filters are also featured.


The EQ module features the familiar Black-knob type SSL EQ, with the usual colour-coding for the four bands. The EQ In button is central, adjacent is a G-EQ selector button which makes the shelving steeper and adds overshoot, or undershoot (if cutting) below the selected HF frequency (or above the selected LF frequency). Additionally, this mode sees bandwidth vary according to gain for the parametric bands. The EQ sounds exactly the same as the console EQ, clean and tweaky.


So, to the mixer. The Line Return module features four line inputs. The rear of this module features two D-Sub 25 pin connectors, allowing provision for fully balanced inputs and returns on one connector, and Insert Sends and Returns on the other. The Insert Send is simply a parallel of the Line input. The Insert Returns are switchable via separate Insert button on each channel. On the front, each channel features a Level pot with calibrated centre détente and a tri-colour signal level LED , a centre-détenting panpot, and in addition to the insert buttons there are Solo and Record Buss routing buttons (channels normally route to the Mix Buss). It’s crowded, but all buttons are sensibly accompanied by LEDs. The Master module acts in conjunction with up to seven Line Return modules. Further racks can be chained with a Master Link D-Sub, (although this does not feature on earlier X-Racks), allowing bussing and soloing across very many channels.


The two D-Sub connectors on the rear of the Master module provide (in conjunction with front panel pushbuttons) Main and Alt Monitor outputs, Mix Insert Sends and Returns (these can also be selected to sum with the Mix buss), (Stereo) Record and Mix buss outputs (the Record buss can also be summed with the Mix), External Inputs (2-track monitor) and Follow Monitor outputs.


Furthermore, the front panel provides a Headphone jack. Small LED meters show monitor levels, and there are knobs for Mix, Solo and Monitor levels. Like a proper console there are Mono, Dim and Cut buttons. Dim level is even adjustable via the Recall section. Separate Monitor and Mix sections allow one to monitor External inputs or listen to the Record and/or Mix busses. One can easily create separate record path and monitor mix setups using the two different stereo busses, it is an elegant and logical system.


Absent from the Line Return modules are any Auxiliary Sends; one must route from within a DAW directly to outboard or headphones, making this X-Rack configuration perhaps more of a summing mixer, albeit with the huge advantage of Recall. But for summing, the (even newer) eight-channel module is probably more appealing. To use the X-Rack as a centrepiece of a studio, careful decisions about placement for ergonomic convenience must be made – controls and legends are tiny, and you need to have the Master section within easy reach. There are interesting possibilities here, there is no question about the sonic quality (apart from the noisy Total Recall), and I suspect further modules may be on the way to make even more of this system.




Excellent Total Recall implementation; Similar circuitry and sound quality to large-format SSL consoles; Clean, High-performance audio quality; Comprehensive Master section module; Ultra-compact mixer format




No Aux Sends on Line Return module; Less ‘character’ than most summing mixers; non-standard D-Sub connections; Audio interference in Recall mode


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Reproduced with kind permission from George Shilling. Copyright George Shilling.




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