Aphex Channel Instruction Manual download pdf (Page 30)

230

instruction Manual

Aphex Systems Ltd. Model 230Page 28

230

master voice channel

Page 29Aphex Systems Ltd. Model 230

APPENDIX G: THE AURAL EXCITER AND BIG BOTTOM TECHNOLOGIES EXPLAINED

The AURAL EXCITER is an audio processor that recreates and restores missing harmonics. Harmonics are musically and

dynamically related to the original sound, revealing the fine differences between voices and various instruments.

Reproduced sound is audibly different than the original live sound because of the loss in harmonic detail, often sounding

dull and lifeless. The Aural Exciter adds harmonics, restoring the sounds natural brightness, clarity and presence, effectively

improving detail and intelligibility. Using the Aural Exciter on specific instruments and/ or in the final mix brings life back to

the recording.

The original Aural Exciter patent disclosed a method for generating harmonics which was amplitude dependent. In nature,

generally speaking, the higher the amplitude, the higher the amount of harmonics. There are instances, however, in which

there are high level sinusoidal waveforms, which should not have harmonics added, and other instances which have low

level transients, which could be enhanced by additional harmonics. Our latest patent, the Transient Discriminate Harmonics

Generator, recognizes transients (transient discriminate) over a wide dynamic range and generates harmonics on them. The

result is a more predictable and natural sounding enhancement over a wider range of inputs.

The Aural Exciter extends the high frequencies, unlike EQ’s and other brightness enhancers which only boost the high fre-

quencies and often alter the overall tonal balance. The stereo image is enhanced with the Aural Exciter, resulting in a greater

perceived loudness without an introduction of noise into the audio path.

The Aural Exciter is a single ended process, that can be inserted at any point within the audio chain. The input signal is split

into two paths. One path goes to the output unmodified, while the other path, known as a sidechain, goes through the

Aural Exciter circuit which is comprised of a tunable high pass filter and a harmonics generator. The Aural Exciter circuit

applies frequency dependent phase shift and transient discriminate harmonics. The output of the Aural Exciter’s harmonic

circuit is mixed back with the unmodified signal but much lower in level. When used at nominal settings, the Aural Exciter

circuit does not add significant level to the original signal. Even though the added information is low in level, the perception

is a dramatic increase in mid and high frequencies.

Another exclusive Aphex patent, Big Bottom, provides a stronger, more powerful bass, increased sustain and density with-

out an increase in the peak output. While static bass-boost EQ’s and subharmonic generators will increase the bass energy

level, the resultant large boost in peak level often increases overload distortion.

Big Bottom resembles the Aural Exciter in that a processed signal is mixed back into an unmodified signal to produce an

enhanced output signal. The sidechain path goes through the Big Bottom circuitry, comprised of a variable low-pass filter

and a phase and dynamics processor.

Big Bottom circuitry dynamically contours the bass response of a complex range of shapes in the 20Hz to 240Hz range. Big

Bottom increases the perception of low frequencies without significantly increasing the maximum peak output. The bass

frequency response is dynamically optimized to isolate and enhance the lowest bass frequencies to provide a deeper and

more resonant bass.

Input

Sidechain

Processing

Original Signal

SUM

Output

SIMPLIFIED SIDECHAIN DIAGRAM

1 2 ... 25 26 27 28 29 30 31 32

Comments to this Manuals

No comments

Aphex Channel Instruction Manual Page 30

Comments to this Manuals

Related products and manuals for Audio amplifiers Aphex Channel