Guitar Multi effects Pedal connected to amp disables amp distortion

Question

I am a guitar player and I recently got a Zoom g3xn multi fx pedal as well as an Orange Micro Dark amp. I have been using the pedal’s amp and effects models connected to the Fx return of the amp and it has worked perfectly. However, when I connect it to the front of the amp it produces volume but the distortion control on the amp does not work; no matter where the gain knob is, the sound is clean. This is true even if no effects are activated on the pedal. My signal chain is simply guitar into pedal into amp. The problem only exists when the master volume on the pedal is low but that is the volume at which I use it as otherwise it is too loud. What could be causing this problem? Any help is greatly appreciated!

Edit: My speaker cab is a 1 12 and Celestion vintage 30 loaded. Everything works fine when just running straight into the amp: I can get nice distortion at low enough volume. The problem is basically getting the same volume and tone going through the pedal into the amp as going straight into the amp.

Answer 1

It's important to realise that a gain control knob works in principle in exactly the same way as a volume control knob: it regulates the signal level. The only difference is that a gain control is located at the front end of the amplifier circuit, a volume control at the back – i.e., a gain knob regulates the signal level inside the amplifier circuit, the volume knob only the level after the circuit. And overdrive is not an effect you somehow add to the signal with the gain control, rather it's simply the result of a signal passing through an amplifier circuit which is too strong for the circuit to properly “keep track” of it.

So, when you put you multi-FX pedal in front of the amp, its volume knob really does literally the same thing as the amp's gain knob. Specifically, if you turn down the multi-FX volume, you're turning down the amp's gain, and therefore it doesn't have enough signal level anymore to go into distortion.

If you want your amp to go into overdrive but still have low volume, the only way is to turn down the amp's volume (or “master”) knob. Note that if it's an all-tube amp, even that will remove some of the distortion (because the master volume still sits before the last power amp stage). The input signal must be high for distortion to happen.

Answer 2

There are a lot of unknown factors here. You say it doesn't work when you go guitar -> G3XN -> amp, but you didn't mention going straight guitar -> amp (no effects loop), set at the same comfortable level. The master volume can have a big effect as well. Generally speaking, low gain high master volume will result in a clean signal at a given volume. High gain low master volume will result in a dirtier signal given that same volume.

My first course of action would be to turn the master volume down to about 9:00, then turn the output volume of the pedal and the amp gain to about 12:00.

I suspect the G3XN is a red herring. Overdrive/distortion is a result of the signal clipping in some way. Think of clipping as the signal "maxing" out at a set voltage, say 2 V peak-to-peak (2 Vp-p). We'll call this the "clipping voltage". The Gain knob amplifies the signal until it hits that clipping voltage. The "harder" it hits that set voltage, the more distorted it will sound. If the input volume is too low, the signal will never reach the clipping voltage, and never distort.

Another variable is the speaker cabinet; you didn't specify what you're using. A 4x12 cabinet will in general be way louder than a 1x10.

Answer 3

In my experience, Zooms are all kinda weird pedals — pretty good, but they do odd things sometimes and even don't play well with each other...which is a huge problem for my situation. It sounds to me like your Zoom pedal or your amp head is messed up. Something is wrong with one or the other. Those are the only other explanations, unless you seriously don't have your Zoom turned up. It's absolutely necessary to have the Zoom volume up to at least 20 or 25 to be at unity gain level with almost any normal amp. Then turn your master volume in the amp as your main volume control.

Another thought: can it be that the amp is just too loud for your low volume situations? This is the absolute only other way that this isn't working for you. Maybe the amp just doesn't turn down as low as you want it to, which would result in having the exact issues you are having. This can be a common problem for those new to the guitar.

Answer 4

One solution that is somewhat controversial among amp owners is called a Power soak. I've known some guitarists who have used them and had no problems with their amps, but I've also heard horror stories about players burning up their output transformers while using them. If you choose to use one, I recommend doing so judiciously. Understand it's always possible to cause yourself some problems while trying to push the limitations of your equipment. A power soak is connected between the amplifier output and the speaker and "soaks up" the juice that would normally be driving the speaker resulting in a lower level of sound actually being produced. This allows the player to crank up the amplifier volume controls to overdrive while keeping the over all volume at a reasonable level. I recommend getting one on a trial basis before making the final purchase to avoid buying a device you might not be very happy with.