Arturia 1973-Pre, User Manual

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4. 1973-PRE OVERVIEW
As we said already in the Introduction, the Neve mixer channels (preamps and EQs) have
become industry favorites since the time he made the first EQ units for Philips in 1964.
Neve circuits usually employed a simple 3-band EQ, consisting of high and low shelves with
a bell mid band. The shelves used a Baxandall type design providing a High Shelf with a
fixed frequency and a Low Shelf with some selectable switching frequencies. These Shelf
EQ bands usually provided a boost/cut range of +/- 16dB. The Mid band usually had an
inductor-based bell design with also a fixed number of selectable switchable frequencies,
and a boost/cut range of +/- 18dB.
To complete the set, a High Pass filter was also added, again with a choice of several
switchable fixed frequencies.
This was also the design of the celebrated Neve 1073 that was the basis of the present
Arturia emulation. However, some modifications were introduced.
The most notable is the changing of the Midrange Bell and Low Shelf bands from switchable
to sweepable. This allows a much wider range of choices, since we can now use ANY
frequency within the range of both EQ bands.
In addition to these, the High Pass filter also has sweepable selectable frequencies between
the lowest and the highest. Only the Off point is a switch.
The plug-in works as a Single Channel or as a Double Channel, according to the audio
channel it is inserted on. In Single Channel we just have Mono mode, but in Double Channel,
we can use the plug-in in Stereo mode, Mid/Side mode and Dual Mono mode.
4.1. What is a preamp?
A preamplifier (preamp or simply "pre") is a device that takes care of the first stage of
amplification. It is usually designed to boost a weak electrical signal to "working level", to
make it strong enough to be noise-tolerant and for further processing, for example in a
mixing desk. The working level is usually called "line level".
Many of us probably still remember the days of vinyl records. Vinyl records were played by
turntables, a device which had an output with a completely different impedance than, for
example, a tape recorder. The turntable output signal was much weaker. To drive it to a level
strong enough to be audible meant that it had to pass through a circuit that would amplify
it to a level where it could be passed to the main audio amplification circuit. More than that,
the circuit also had to transform the tone, in order to decode the special RIAA encoding tone
curve. Without this previous stage, the signal would be weak and distorted harmonically.
This circuit was (is) a preamplifier, and was usually part of any Hi-Fi amplifier (those special
inputs labeled "phono", which seem to be coming back as of lately). It should be mentioned
that Arturia's AudioFuse audio interface also features a microphone preamp circuit, and it
even features the special RIAA preamp we just mentioned.
But there are other kinds of preamplifiers, that do other things. The preamp devices that
brought us to this point are those typically used to amplify signals from audio sources
such as microphones and instrument pickups. Because of this, preamplifier circuits are now
usually built into the audio mixers (and are included in many computer audio interfaces
too).
But it wasn't always like this. There was a time when preamps were separate units that
received the signal from microphones and delivered it to the mixing circuit. The Telefunken
V76 was one of those units. Then they became modules that could be plugged into those
mixers (like the Neve units). Now, they are simply standard equipment. But there are still
many other devices that use preamp circuits besides mixers, as electric guitar and bass
players know very well.
18 Arturia - User Manual 1973-Pre - 1973-Pre OVERVIEW