CATALINBREAD / Epoch Bias

The EP-3 Echoplex has been responsible for some of the most iconic tones in rock history, not only as a tape echo unit, but also as a preamp. The Catalinbread Epoch Bias is an extension of the Epoch Boost, which is a compact version of that preamp section.

The new BIAS control on the Epoch Bias adjusts the EP-3's basic gain and body. While the gain itself does not increase significantly, it can be adjusted beyond the original specifications. In addition, the FILTER control provides a classy high cut, allowing you to adjust the advantages of the early to late EP-3.

First released as a solid-state, the Echoplex EP-3 was introduced into numerous recording studios, where guitarists plugged it in before their amps and created guitar tones with a great preamp. The Epoch Boost could be placed anywhere, but most players, including pro guitarists, placed it at the end of the chain like an always-on preamp pedal that adds sparkle at the top while tightening the overall mix.

Catalinbread wanted to see if they could improve it further, so they added a BIAS control that adds a little gain and body by simulating parts outside the original EP-3 specs.

We also tested the early and late EP-3 circuits and found little difference, so we added a FILTER knob that allows you to adjust the tone to those early and late tones, plus beyond. This allows you to adjust the pedal to your operating environment.

The PREAMP control simulates the original EP-3 volume control. Originally, the EP-3 circuit adds very little gain by itself. Therefore, the BOOST knob allows for punchier tones with more gain.

It is truly the most flexible and easy-to-use EP-3 preamp pedal ever.

■Controls
PREAMP: Basically acts as the volume control for the EP-3, but this control is not just a volume control, it is the panning of two different signal paths. This control combines the preamp and mixer circuits, with the first half of the knob being the volume and the second half being the frequency boost: before 12:00, the entire frequency range is pushed gently, with maximum loudness around 2-3:00.

BOOST: Adjusts the volume of the sound adjusted by the PREAMP knob. Counterclockwise minimum is the original EP-3 circuit, clockwise increases volume and adds punch.

BIAS: The original EP-3 preamp circuit had gain and volume determined by a single resistor value in the circuit. However, when the EP-3 was first released, the gain of the preamp itself varied because of the tolerance of that component, and the BIAS knob allows you to adjust that value to control the gain and sound thickness of the circuit. This knob produces a crackling noise when turned, but it is normal operation.

FILTER: The first few hundred early units of the EP-3 had different preamp circuitry than the later units. The early ones have a slightly brighter tone than the later ones; the FILTER control is a gentle high-cut filter that covers both tones.

■Power Supply
Epoch Bias is powered by a standard center-minus DC 9V adapter. Current consumption is 18mA. Do not connect any power supply other than 9V as it is internally boosted. Batteries cannot be used.