Apple Logic Express 7 - Manual (Page 38)

38 Chapter 5 Distortion
Guitar Amp offers a range of Amplifier and EQ models that can be combined in a
number of ways. The EQ models are equipped with the Bass, Mid, and Treble controls
typical of guitar amplifiers.
Four different amplifier models can be accessed via the Model radio buttons at the top.
• British Clean—simulates the classic British Class A combos which have been
continuously produced since the 1960s to the present, without any significant
modification. This model is ideally suited for clean or crunchy rhythm parts.
• British Gain—reproduces the sound of a British tube head, and is synonymous with
rocking, powerful rhythm parts and lead guitars with a rich sustain.
• American Clean—emulates the traditional full tube combos used for clean and
crunchy sounds.
• American Gain—emulates a modern Hi-Gain head, making it suitable for distorted
rhythm and lead parts.
The entries in the pull-down menu at the top are Settings that refer to the simulated
Amp models. Accordingly, the British Crunch, British Lead, American Clean, Crunch, and
OverDrive select the appropriate Amp models, and apply new EQ and other settings.
You can, however, combine any Amp model with any EQ or other parameter settings,
as required.
At the top of the slider section, you will find the Pre Gain control, used to set the pre-
amplification level of the input signal. This control has different effects, dependent on
the selected Amp model. As an example: A maximum Pre Gain setting produces a
powerful crunch sound when used in conjunction with the British Clean Amp model,
but the same Pre Gain setting results in a heavy distortion—suitable for lead sounds—
with the British or American Gain Amp models.
Directly below, you will find the Low, Mid, and High controls. Use of these sliders allows
you to adjust the frequency ranges of the bass, mids, and treble as desired.
Presence is an additional high frequency control which exclusively affects the output
stage (Master) of the Guitar Amp plug-in.
The Master slider controls the output volume of the amplifier (to the “speaker”).
Typically, in tube amplifiers, an increase in the Master control level produces a self-
compressed and saturated sound, along with increased level, resulting in a more
distorted and powerful amp signal. In the analog domain, this results in an extreme
increase in loudness. In Guitar Amp, the Master control influences the sonic character.
The Output Level slider serves as a final level control for Guitar Amp’s output. It can be
viewed as a volume control “behind the cabinet”, and is used to set the level that is fed
into ensuing plug-in slots on the channel, or into the channel output.
Note: This parameter is very distinct from the Master control, which serves a dual
purpose—for sound design, as well as controlling the level of the Amp section.