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Zero-Loss FX Loop Kit

Now on sale!

First time ever reduced price on this best of it's kind FX loop.

Steve Miller's unmatched FX loop design in kit form. 

We officially support this loop when installed in Marshall 1959, 1987, 2203 and 2204 models, also authentic replicas of these amps. The installation instructions are specific to this style of amp, with the long tailed phase inverter circuit. The loop will also work great in many, many other tube amp circuits, but we do not supply specific instructions. Please download the instructions from the link below to determine if the loop is compatible with your amp. Also, any good tube amp tech/designer can tweak this loop to work in most applications. It has been used successfully in tube amps from 18 to 200 watts.

From Steve:

This is an entirely new loop, designed specially for Metro kits and specifically with these classic Marshall circuits in mind. The idea here was to make a loop that truly left the tone, and just as importantly the "feel", of a cranked Super Lead unchanged. To not be able to hear any difference at all. Those with fine-tuned ears know that's not an easy task. Even "good" loops are still audible or affect the feel in some way. You work very hard to achieve a certain tone, so a loop should NOT change that. A tube loop may "sound good", but an ideal loop should not "sound" at all - that's the goal of this new loop.

There is nothing else out there like this loop, it's a new design using unique high-voltage devices that actually run at high voltage. These little devices operate much like an "ideal" tube, but without all the drawbacks of a real tube (i.e. installing and wiring up a new socket, potential heater hum, tube noise, limited gain, lack of headroom, "coloration", etc.). Hundreds of volts of actual signal (way more than needed) can be buffered to true guitar/pedal level, then returned just as strong as where it started--distortion free. This is something no 12A-7 tube loop could do, forget about your typical SS loops. These devices simply will not clip, add distortion or compress the tone in your Metro amp. Even the signal phase is preserved through the loop.

To handle the extremely stringent demands these loops had to pass, these special high voltage SS devices were the absolute best choice. Nothing else comes close.



Download the instructions here:  FX Loop Instructions V 1.4 

And here's a link to more info on the MetroAmp forum:


Loop dimensions are 3 3/8" x 1 3/4"


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