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Apex PE 133 MkII Paragraphic Equaliser (part 3)



No LCD, no nudge buttons and no excuses. These units are fitted with a full
complement of physical controls, fifty-five on the PE133 excluding the power
switch. The corollary of this is that there is no MIDI facility and no programmability
so we are talking about real old-fashioned sound engineering here. On a unit
with so many EQ sections the first thing I look for are in/out switches, and
there is no shortage. Obviously each section of EQ is going to make a little
bit of noise even when set flat, so it’s good to see that there are six
in/out switches so what you don’t need doesn’t get in the way.

If you have a simple EQ task then perhaps you will start with the low pass
and high pass filters. These have a slope of 12dB/octave and range between 2kHz-40kHz
(high pass) and 15Hz-300Hz (low pass). Just above them is a level control with
a calibration range of minus infinity up to +6dB. If your instincts lead you
to the graphic section then you will notice that there are 30 bands and a scale
switch which sets the range of cut or boost on each band to 6dB or 12dB. I liked
the sound of the constant Q filters rather more than conventional graphics and
I felt that I had much more control over the sound than usual. It is also much
easier to make the sound pretty horrible by having large differences between
adjacent sliders, but then that’s up to your sense of self restraint!

Switching the graphic out of circuit and moving on to the parametrics we find
three individually switched bands, each of which covers the full range between
18Hz and 20kHz. A range such as this on one knob would provide only a very coarse
control and Apex have thoughtfully included a three position range switch, so
you can choose between 18Hz-200Hz, 180Hz-2kHz and 1.8kHz-20kHz. (This switch
is actually closer to the Q control so you might mistakenly think that you could
set a Q of 80 in the x10 position!). For fine tuning there are also ‘vernier’
controls with a range of ±10% over the main control. As I mentioned earlier,
the gain of each band ranges from minus infinity (actually specified to be -45dB)
to +15dB.

One of the things to watch out for with equalisation is the potential for
creating an overload by boosting several sections at around the same frequency.
This could easily happen with four sections which have the capability to boost
a single frequency by as much as 57dB. The overload detection system here works
well and monitors a number of potential overload points in the circuit. I couldn’t
hear any clipping that wasn’t clearly indicated by the LED so all must
be well. One slight anomaly I found was that the overload LED lights even when
the graphic is switched out of circuit, but only when the parametrics are switched
in. I’m sure that there must be a good reason for this and I don’t
see why it would be any drawback in use.

I found the PE133MkII to be a very capable piece of equipment with no significant
drawbacks. It’s quiet with low distortion. It has relay bypass on power
off (as all equalisers should, and delay units too), and it sounds good. What
more can you ask?

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David Mellor

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David Mellor