The Empress Phaser's phase is usually controlled by an LFO. In submode 8, an expression pedal can be used to control the phase instead. This means you are able to "freeze" the phaser. While in this submode, you can still modify the sound of the phaser through the blend and gain knobs, and the stages and resonance switches.

No unfortunately. If you just gotta have presets, there is a way. 5 of the parameters on the Phaser (speed/ratio/sensitivity, width/release, waveform/automode, mode, and speed range/attack) can be controlled with MIDI. So you'd need something that would output MIDI program change messages. The manual lists all of the MIDI CC's you'll need to know, as well as the process for setting up MIDI on the pedal.

The Phaser has true bypass switching. It uses a relay to switch.

The Empress Phaser has a microcontroller in it that has firmware loaded on it. Occasionally we'll make small changes to the firmware. To find out which version of firmware you have, unplug the power from the Empress Phaser, then plug it back in. You'll notice that the LEDs above the tap (red LED) and bypass (blue LED) stompswitches flash in a pattern of long and short red flashes. (Actually, if you don't get any flashes, that means you have version 0). It always starts with a long flash. A long flash represents a 1, and short flash represents a 0. The resulting pattern of 1s and 0s is a binary number that gives you the firmware version. If you know how to convert from binary to decimal, you're all set. If you don't, you can do the conversion here. Or you could just email us the pattern and we'll tell you!

For example, if you get a pattern that goes "long short long," that represents 101, which means you have firmware version 5. If you get the pattern "long long," that represents 11, which means you have firmware version 3.

The pinout of the expression pedal should be TIP=output, RING=input, SLEEVE=ground. There's a list of expression pedals on this page that work with the control port. They should also work with the blend exp input. Volume pedals probably have too high of a pot resistance to work with the blend exp port, but you can give it a shot!

Mission EP-1 and EP-2 (no polarity switch, polarity switch, respectively)

M Audio EX-P (has polarity switch)

Roland EV-5

Lead Foot LFX-1

Boss FV-500L

Boss EV-30