Drawmer MC 3.1, Руководство пользователя

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MC3.1
- Monitor Controller
Active vs. Passive Circuits
There is a great debate as to which is best - a passive or active monitor control
circuit. The theory is that passive monitor controllers must be best, since they
do not add transformers or other components to the signal path, along with the
noise and distortion that they can bring, however they have severe disadvantages
over active circuits. The most significant is that the output impedance of the
connected source equipment and the input impedance of the power amp or
active speaker will affect the workings of the passive controller - each needs
buffering to remain reliable and consistent, otherwise level matching problems
will be inevitable. Since even the best cables have capacitance, it is extremely
important to keep cable lengths to an absolute minimum (i.e. less than a couple
of meters) to avoid signal degradation especially in high frequency signals.
Long cables will act like a simple low frequency filter.
Furthermore, it is incredibly difficult to get a mono signal from a passive circuit
without affecting the sound so any kind of reliable mix checking becomes near
impossible.
Active designs make it easier and more reliable to guarantee a high performance
level as the signal attenuation and switching is actively buffered, as well as
providing complete control over distortions, crosstalk, frequency response, and
transient fidelity. Moreover, cable lengths of tens of meters should not be an
issue. Furthermore, it makes it possible to introduce mix checking features that
would otherwise be missing. The disadvantage with active monitor controllers
is that the electronics have the potential to introduce noise and distortion.
Designing a clean monitor control system is far from simple, however, using
only the very best components and clever circuit design, with the Drawmer
MC3.1 we have overcome all of these problems and managed to combine the
best of both - whilst retaining the transparency and responsiveness that a
passive circuit would bring with the advantages of an active one.
Know your Left from your Right
It is useful to get into the habit of using the Left / Right Swap button every now and
then when working on a stereo mix. We get so used to hearing a mix as it’s
developing that its’s easy to get a stereo imbalance. If when pressing the Swap
button the stereo image is mirrored around the centre, and you notice that it’s more
prominent in a certain ear then the stereo image is likely to be out of balance. If it is
unclear that it has altered then the stereo mix should be balanced.
The Swap button also highlights problems with the monitoring system such as if
piece of audio that is panned centrally but actually sounds off centre. If by pressing
the button the stereo image remains the same then it shows one speaker is
louder than the other and the system should be recalibrated. If the same audio is
mirrored around the centre then it shows that the fault is within the mix itself.