Keith Hilton
From:
248 Laurel Road Ozark, Missouri 65721
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Posted 26 Aug 2018 5:20 pm |
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I am constantly asked where in the signal chain is the best place to put a particular effect pedal. This is almost impossible to answer for a number of reasons. I always tell people the best solution is to try the pedal in different places, and see where in the signal chain it works and sounds best to you.
Many people use the chart below to organize their signal chain of effect pedals.
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Signal Reshaping
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Overdrive
Distortion
Compression
Ring modulation
Pitch shifting
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Signal Augmentation
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Flanging
Phasing
Chorus
Delay
Echo
Reverb
Signal reshaping comes before signal augmentation in the signal chain.
The thing that confuses all of the above is amount of voltage being fed to the input of effect devices in the signal chain. Remember, everything in electronics boils down to only 2 things, voltage and current. Even the word impedance boils down to voltage and current.
With a guitar, volume pedal, and amplifier, you have a choice of 3 places to put effect pedals in the signal chain. Voltages at the 3 possible places vary in huge amounts.
The lowest voltage point is between a guitar's pickup and the volume pedal. The exception is when the guitar's pickup has a preamp that boosts signal.
The voltage coming out of a volume pedal is lower than that coming from the pickup, unless the pedal is wide open. A volume pedal controls the range of voltage produced by the guitar pickup.
The send and return on a amplifier has a preamp that boosts the signal sent to an effect device up to line level. Line level being up to one volt. Whereas a instrument level signal from a magnetic pickup can be a small fraction of one volt.
Of course voltage can vary depending on how hard a string, or strings are picked. More voltage is produced by more strings being picked together.
The strongest voltage points then would be: After a preamp boosting a magnetic pickup, and before the volume pedal. Also in the send and return loop of an amplifier.
Effect pedals are designed with a certain input and output impedance. The amount of voltage feed to the input of an effect pedal, can change how the pedal operates. I have always maintained that some guitar pedals were designed to see the low level of a magnetic guitar pickup. Other pedals are designed to see stronger line level input signals.
A perfect example of how input voltage changes the operation of an effect pedal is the distortion pedal. Most distortion pedals alter the top positive, and bottom negative part of the sine wave. The breakover voltage of a diode junction is somewhere around 6.5 volts. Also distortion schemes involving the base of a transistor, JFET, or other device is dependent on voltage.
So what does all this boil down to? Like I said earlier, everything boils down to voltage and current. The best answer of where to put your effect device in the signal chain is to experiment. Your ears will tell you where it fits best. |
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