Skip to content
Red-Eye Preamp - Effects Loop?

Red-Eye Preamp - Effects Loop?


Is there a certain reason for having an effects loop for other pedals, as opposed to it being in line like a regular pedal rig?



The idea behind the Red-Eye design is to make it simple for a performing musician to have great sound in live performance situations. 


There are three main features that help do that...

1) Bring in a clean, natural, acoustic signal into the system.  Allow good acoustic instrument pickups to couple into the preamp field effect first stage by properly matching the impedance of piezoelectric pickups.  Handle the signal with studio-quality, low noise, low distortion analog electronics.  Buffer the signal to provide sufficient drive to feed the Red-Eye’s balanced output transformer and to drive any pedal the musician may want to connect to the Red-Eye’s Effects Output.


2) Provide a simple high quality effects loop so a musician can use a tuner and effects pedals he or she may be accustomed to. Provide a built in Solo Boost Button so the musician can control the signal level when called upon to solo or if he or she changes from using a pic to finger style.


3) Provide a very high fidelity balanced output to supply a sound system with a very clean signal and to bring in XLR Phantom Power to run the Red-Eye without having to use a battery or make other power connections.


Most of the acoustic players that use the Red-Eye play it by itself or with just a stomp tuner.  They ask a venue’s sound tech to start out with his mix board EQ flat and then adjust for the house room acoustics.


Pedals in line vs Effects Loop...

The sound you get with a high impedance passive pickup depends on the impedance of the device it’s feeding.  Not many devices match the impedance of the pickup properly.  Connecting a pedal between the instrument and the Red-Eye’s Instrument Input will destroy the impedance match between the pickup and the Red-Eye.  If a piezo pickup’s impedance isn’t properly match it may ring or generate wolf notes that are almost impossible to EQ out.


So connect a passive pickup instrument directly to the Red-Eye and put pedals in its buffered Effects Loop.


An active pickup is just a passive pickup and a built-in preamp.  Some instruments with active pickups may be buffered well enough to drive pedals in-line.  However, I’ve measured several active pickup systems and did not find one where the preamp’s input impedance properly matched the pickup.  The pickup may be fine, but it’s signal can’t get into the preamp properly if the impedance isn’t properly matched. And I’ve been to too many gigs where the battery in the instrument dies during the show.  Nasty!  I don’t think batteries belong in fine instruments.


Daren Appelt, Engineer, Fire-Eye Development, Inc.

Previous article Red-Eye Preamp - AC Power Ground Loop Hum Issues

Leave a comment

Comments must be approved before appearing

* Required fields