To enhance the artistic intent of the producer/mixer's original stereo mix balance is the ultimate goal of any professional mastering engineer. Mastering engineers stake their reputations on making crucial sonic decisions based upon two things: their own experience and their trust in their tools and monitoring system. Maselec's MTC-1 allows those decisions to be made instantly by offering a powerful yet flexible collection of routing and monitoring facilities and the freedom to audition/use up to six stereo inserts at the same time.

The insert routing design covers configurations such as parallel and additive processing, post output processing, and the ability to audition inserted processors "swapped" in signal chain order with a touch of a button. Auditioning various combinations and orders of external stereo outboard processors to evaluate their value (or not) when used is now easy. The MTC-1 also incorporates monitoring and scalable metering facilities to verify and check the audible merit of the mastering engineer's work (subjectively) in an (objectively) accurate and empirical way.

To accomplish this sonic legerdemain, the MTC-1 is divided into four sections. The Input section selects between two stereo sources called S1 and S2 with separate phase (absolute polarity) flip and cut buttons for the left and right channels. There are large individual, left and right resettable level controls in 0.5dB steps from -5 to +5dB range and a fixed +5dB level "bump" button if more is required. There are also 12dB/octave high and low roll-off filters with six, selectable corner frequencies for each. These are very smooth filters with a proportional slope design that steepens towards the lower and higher frequency extremes--Maselec says that this feature optimizes these filter's subjective performance.

The Insert section has six, stereo insert points each configurable in very powerful ways. Any processor connected to Insert 1 is usable normally (as serially in a chain) or as a M/S or Mid-Side processor with a front panel difference signal gain control adjustable in 0.1dB steps. Insert 1 and 2 are reversible in their chain order--swapped with the Flip button. Insert 4 and 5 also flip but the processor connected to Insert 4 will crossfade between Insert 2 for parallel processing--wet/dry compression and/or the Add button allows Insert 4's processor to be mixed into the main output like a reverb return. Insert 6 is available like the others but the Post button routes it to the final output of the MTC-1--such as for adding a brick-wall limiter.

Section 3 is the Output section with left and right gain controls, L/R Cut buttons and the Elliptical filter with 20 frequency choices below which all non-correlated signals (non-identical signals) are made mono. The Stereo Width control circuitry is the same as in the Maselec MTC-2 unit and is engaged with the Image button. Image is a great way to A/B the effects of an enhanced stereo width via the unit's built-in M/S encode/decode matrix.

Section 4 is the monitoring section and has four stereo source inputs: S1 and S2 are from the aforementioned Input section; S3 is for another external stereo source; I/P is the Input Section after any gain adjustment and filtering; O/P is the output of the MTC and S4/DAW is useable for analog playback of your DAW or stereo tape deck.

There are five monitor modes: Stereo, Left or Right channels only, plus L+R Mono and the Diff mode is useful to check for mono capability when using extreme M/S insert processing. The 23-step monitor volume rotary switch uses precision resistors for matched L/R gain from -55dB and 0dB. There are Dim button, separate L & R cut buttons along with monitor Main or Aux speaker choices and meter scaling features that are all very important features to any mastering engineer to do their best work.

I found the MTC-1 to exceed all my expectations--there is no sacrifice in headroom or sound quality within the unit itself no matter what configuration of any and/or 6 inserts or the M/S processing amount. I found the interrelationship and balance of all frequencies, the left/right channel balance, the phase integrity, dynamic range and, most importantly, repeatability of the MTC-1 astounding in its accuracy.