EQ Section

Click the “EQ” switch on an Input Strip to expose the EQ controls.

Channel Strip EQ & Filters

The channelstrip EQ emulates the famous Harrison 32Series EQ, which was used on countless popular albums.

The Channelstrip EQ provides a very wide range of frequency and gain changes ( up to 15dB! ) to help tame your tracks. The high and low bands are shelving filters for general tone sculpting, while the 2 middle bands are “proportional Q” design. Optionally, the High and Low bands may be switched to “bell” ( peaking ) shape with the small mode switches at top and bottom.

*The proportional-Q design was used in the original Harrison consoles to allow an engineer to use the EQ as either a subtle tone shaping tool, or a steep filter problem-solver, with only 2 knobs. As the gain is progressively increased (or cut), the bandwidth becomes progressively narrower (the Q increases). A typical technique is to increase the gain to maximum, sweep the frequency to find an offending sound, and then turn the gain to minimum to “notch” out the unwanted frequencies.

*NOTE: In the original 32C EQ, and the Mixbus emulation of it, the frequency and gain knobs are labeled as if the “bell” knob were engaged, however the default mode is shelving. In shelving mode, the available gain is +/-18dB and the frequencies are different (because it is a filter corner freq, not a bell center freq). We have decided to keep the labeling of the knob the same as on the actual 32C console. Please note that the knob is labeled for a mode that is not the default, and the text display does not match the tick marks around the knob.

Specifications:

Separate “In” buttons for 4-band EQ; 2-band Filter section.

Gain Range +/- 15dB

Frequency Ranges (adjustable):

• HI: approx 900 Hz to 13,000 Hz
• HI MID : approx 400 Hz to 6,000 Hz
• LOW MID: 200 Hz to 3,100 Hz
• LO: 40 Hz to 600 Hz
  

Filter Frequencies:
LPF 12 dB/octave, frequency range (approx) 160 to 20,000 Hz
HPF 12 dB/octave, frequency range (approx) 20 to 3,100 Hz

NOTE that the filters have a generous frequency overlap. It is possible to adjust the frequency knobs on the filters such that there is NO signal coming through! This was also possible on the original 32C analog console, and was a favorite tactic of control room pranksters.

*Care was taken to model the performance of the analog circuit, and variations in the knob resistor values are used to drive the model, rather than more typical “frequency” settings. Due to that, and also the resulting interaction between bands, you will notice that the reported band frequency can change with the gain setting, and vice versa…particularly in the “shelving” mode.

Mixbus EQ

Each of the 12 mixbuses provides a 3-band “Tone” control.

The Mixbus EQ provides carefully chosen center frequencies, and wide tone-shaping shapes, to provide overall tone control of the signal on the bus. The gain range is slightly lower than the channelstrip EQs, and the bandwidth is wider, to provide more nuanced controls.

Specifications:

Gain Range +/- 9dB

Frequency Ranges (fixed):

• HI: 2000 Hz Q=1.0 Shelf
• MID: 800 Hz Q=0.7 Bell
• LO: 300 Hz Q=1.0 Shelf
  

Master Bus EQ

The Master Bus EQ provides very fine control of the final output tone. The band frequencies are carefully chosen to address the problem areas of a typical pop music mix: very low frequencies, mid-low frequencies, and “very high” frequencies ( leaving the primary mid-band relatively unchanged, as the reference ) The limited gain range ( +/- 6dB ) provides for very fine adjustments.

Specifications:

Gain Range +/- 6dB

Frequency Ranges (fixed):

• HI: 4000 Hz Q=1.0 Shelf
• LO/MID 300 Hz Q=0.7 Bell
• LO 90 Hz Q=1.0 Shelf
  

*You can copy EQ settings from one track to another by dragging the EQ processor (in the processor list at the top of the channelstrip) onto another channel’s EQ processor.

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