This guide will provide a brief overview of Warm Audio's EQP-WA, a recreation of the world renowned tube EQ, the Pultec EQP-1A.
1. The unit has two stepped, semi parametric bands which share a bandwidth (Q) control. Also features a Low pass Filter (Cut High Frequency).
2. The far left control is the boost (amplification) for the frequency of the first band.
3. The boost & cut low frequency pot controls what centre frequency the band is set to. This pot is stepped so only the named frequencies on the unit can be selected. This ranges from 20Hz — 800Hz.
4. The cut (attenuation) pot controls how much you attenuate the centre frequency by.
It is possible to boost and cut the same centre frequency, because both controls share the same frequency control.
This causes a dip before the centre frequency, then a boost slightly afterwards, this is known as a resonant curve.
This helps to emphasise the boost and can be used in very creative ways.
5. The fourth pot controls the bandwidth (Q value). It ranges from sharp to broad, 0 — 10. However in Q value terms sharp would be a high number >10 Q to create a narrow bandwidth. While broad would be a low number <0.2 Q to create a slight curve.
6. The next three controls are the same as the first three, however the High frequency pot steps from 3kHz — 16kHz.
7. The final control to the far right is the Cut High Frequency pot. This control is a stepped Low pass Filter,3kHz —20kHz.
8. This unit is a clone of the famous Pultec EQP-1A, and features Premium grade input and output CineMag USA Transformers. It is powered by two high voltage tubes, the 12AX7 and the 12AU7.
A trick with the original Pultec was to bypass the EQ (using the bypass switch on the far left) and run the signal through the unit purely for the tube and transformer colouration. This is believed by many to add analogue warmth.
1. Make sure the EQP-WA is on, check the switch to bottom right of the unit. The light should be on.
2. Signal coming through but the controls aren’t working? The EQ can be bypassed, the switch to the bottom left needs to be up for the controls to affect the signal.