Part of the fun in collecting pedals is finding new ways to use them creatively in the never-ending quest to define your tone. And while there are no rules when it comes to how one should use a pedal with your guitar and amp setup, there are two ways to introduce your pedals into the signal flow, the front input of the amp and the FX loop, typically found on the back of your amp head or combo. These both serve a specific purpose in how they interface with your pedals and as such can produce substantially different results. Additionally, there are pedals that will sound better when used with the FX loop, which tends to cause some confusion. In this Blog post, I’m going to attempt to help clear the air here and provide you with some audio clips that will demonstrate the difference in sound.
Be the Signal
Let’s start with a solid foundation by identifying and defining the difference between the front input on your amp and the FX loop.
The front input on your amp is provided for you to introduce a signal into its’ preamp, prior to being amplified and equalized. This is the simplest of connections and the first point that you can begin to alter your sound. This is where you’ll likely find a gain knob to help introduce the amps’ overdrive into your signal. Additionally, this is where you can choose between your clean channel or the second channel typically reserved for the amps’ built in distortion.
Once the signal is pre-amplified, it’s fed through the amps’ on board equalization, and finally fed to the Power Amp section. This is where the processed signal is routed out to your cabinet. Keep in mind that this is an extremely basic example of the signal flow through an amplifier and as you can imagine, there are several amps out there that house additional functionality and complications. For the purpose of this Blog, we’ll stick with simple.
The front input is ideal for pedals that are meant to alter the entire signal as its fed into the amp prior to pre-amplification. These are also known as “In-Line Effects”. With that in mind, overdrive/distortion pedals, compressor pedals, and EQ pedals would be the first choice for the front input of your amp.
There are also other pedals that would work well here, such as a Wah-wah, Flanger, Phaser, and Chorus. It really is just a question of what appeals to you as it’s your tone after all.
Additionally, there are also other pedals that can be used here, such as reverb, delay, and tremolo. They would ideally process the signal after your In-Line Effects. This would be a fine solution if you just using the clean channel on your amp exclusively. Have a listen to the following audio clips.
The first clip is an A chord being played through a distortion pedal which is then fed through a delay pedal and finally routed to the front input on the amp with the clean channel selected.
The second clip is a melody line that’s being played through the same setup.
However, if you intend to use the amps’ built in distortion (as many of us do), you may find that the resulting processed signal is unfocused, washed out, and/or degraded. This is the result of the effect itself is being processed prior to the amps’ distorted amplification and equalization.
This may or may not work to your liking, as you can hear in the following audio examples with a delay pedal being fed to the front input of the amp and using the amps’ built in distortion channel.
First, the A chord.
And the same melody line from the previous example.
As you could hear, the delays’ reflections were distorted and muddy, which resulted in a tone that was less than ideal. It might sound cool as a texture to add periodically into your tone (say for a solo), but when playing with a full band, it can tend to hurt the overall sound and tight rhythm.
This is where the FX loop on the back of your amplifier comes into play. The FX loop sends the post amplified/equalized signal out of the amp (The SEND jack), and into a pedal of your choosing. That signal is then processed through the pedal and fed back into the amp before the Power Amp section of the amplifier (The RETURN jack). If used correctly, this results in a much more focused and cleaner tone.
Listen to the following audio examples. In these examples, the distortion channel has been selected on the amp. Therefore, the distortion will sound different here than it did the two previous examples. What you should pay close attention to is the delay pedal, which is connected to the amps’ FX loop.
First, the A chord.
And the same melody line from the previous examples.
As you could hear, using the amps’ distorted sound, and feeding that sound to the delay pedal resulted in a much clearer and defined tone, as the reflections of the delay weren’t pre-amplified or equalized.
Using the FX loop on the back of your amp may be the solution you’re looking for when attempting to keep your tone clear and defined. I hope you found this Blog entry useful and please come back often to find more tips and tricks, as well as the latest in pedal-related news.
Keep on Stompin!