The problems are:

• The difficulty to hear the correct volume of the instruments and mix them correctly into the loop.
• The danger of feedback. Even if the volume is not as high as to create a oscillation, sound from the monitor enters the mike again and is recorded again into the loop, deteriorizing the sound quality and making clean Replace impossible.
  Pressing OVERDUB really just while playing improves this situation a lot. The OVERDUB Mode SUS helps to do this.
• Crosstalk from other instruments and noises into the loop. If the drums are playing next to the percussionist or loud in the monitor, the snare will be looped. Whether this is a problem or not depends on the music and the way the loops are used.
• The physical distance of the instruments and the various postures of playing can make positioning of the pedal board difficult.
  ECHOPLEX pedal boards can be used in parallel. You can have the keys in several places, even in several forms (to operate by knee or elbow, for example)

Basically there are three ways to go:

1. A microphone/sound system only for the loop

This is the most simple, suitable for rehearsals, small shows:

• Connect a clip microphone directly to the ECHOPLEX and keep clipping it to the instrument you want to loop. You can prepare a piece of wood on each instrument so you know exactly where to clip the mic and how loud it is going to be.
• Mark the correct position of the Input control for each instrument so you can adjust it quickly before you play.
• Wind up the Mix control to "loop".
• Connect the ECHOPLEX output to some amplifier (preferably not a guitar amp!) and regulate the volume, so the instruments appear about equally loud direct and from the loop. The sound will not be the same, but this can be interesting even.

2. Mixing on stage or by the band's sound man

The musician or a smart sound man controls the loops from the mixing desk. The sound can be equalized for each instrument and monitored. Thus, the difference between the original and the looped sound becomes small.

The ECHOPLEX is connected like a reverb to an Aux send and returns to a channel (remember to close the Aux in that channel!). The MIX control is way up to "loop".

The problem is the position of the Aux send control in every channel. To optimize cross talk, the sound man should only open the channel that is actually going to be looped.

With this setup you can for example maintain a groove on the congas (Aux closed) and throw a cymbal into the loop (Aux open) without having the congas looped (except cross talk).

The most perfect solution: Headphones (getting popular anyway!).

3. "Electric" percussion instruments:

Could be MIDI sounds, but that's too cold, sometimes.
Instruments like Korg WaveDrum are much better because they bring through details of playing techniques that cannot be recorded by MIDI, but very well in the loop, because there is no problem with noises and feedback.

Maybe we should start inventing "electro-acoustic" percussion instruments in the sense of a electro-acoustic guitar: Little resonance and a pick-up in the right place. The sound can become richer, easier to amplify, and the instrument can be played very dynamically.

Also, a simple piece of metal that has no volume but maybe an interesting sound can turn into a new instrument.

In general, this type of instruments will be lighter and smaller, needs less stands, less space on stage, can be accessed more immediately.

Piezo pick-ups are cheaper than good microphones, need no clamps.

Mixing desks with piezo inputs (impedance > 1 MOhm) are not common yet, but most ordinary ones can be modified easily.

This is the most futuristic way. It will take time and efforts, but we will end up there.

Matthias Grob Salvador, April 96