The Gtown Custom Amps D’Leator External Active FX Loop is a tribute to the amazing Dumbleator tube driven (12AX7) effects loop buffer used for Dumble (and many other) amps. Since the Dumbleator is more rare than a Dumble amp, Gtown Custom Amps has filled the void.

If you use any time based guitar effects (chorus, delay, reverb, phase, flanger) they should never be plugged into a guitar amps input. They should be ran through the Effects Loop so that the guitar signal stays intact throughout the signal chain. Otherwise the pre-amp stages of the amp also boost the affected signal, coloring it, sucking the tone out, deadening it, etc. The only effects you want in the guitar amps input is your OD pedal, if you use one.

This is where an Effects Loop Buffer comes into play. You may ask, why would you want an effects loop buffer at all? I went many years and never used one, but when I did, I then realized all those wasted years of noise, transients and clutter in my signal….which means tone!

First, it is often advantageous to have some effects like reverb, delay, chorus, flanging and phasing, work their magic on your guitar tone after it has gone through distortion pedals and the like (that reside between your guitar and your amp’s input) AND your amp’s preamp. This is particularly true if your amp creates preamp distortion.

At that point in your amp’s signal chain your gear has worked much of its mojo on your tone and it is often the best time to slam it with a time-based effect like those mentioned above. This is, of course, a subjective decision. Some guitarists prefer putting time-based effects in the same chain as their other pedals between their guitar and amp.

Second, the FX loop’s signal is better suited for an Effects Loop Buffer that likes to see “line level” signals instead of the “instrument level” signals that exist between guitar and amp. We won’t dive into the technical definition of line and instrument level signals other than to point out that they are different and some ‘fancier’ gear likes it better when it’s driven by a line level output.

This does NOT mean that you cannot put good old stomp box pedals in an FX loop. If your loop has a line/instrument switch or a Send Level control, you should be just fine. Even if it doesn’t and you want to use a stomp box in a loop – go for it! It may be that the signal levels in the loop won’t be matched perfectly, but you won’t hurt anything – depending on what’s in the loop you may hear more ‘noise’ (hiss), but that again is a subjective decision: is it good enough or not? Only your ears can make that determination.