the answers
Harry, I applaud you for trying to make your electric guitar pedals work with your bass; it’s always worth a go even if perceived wisdom suggests it shouldn’t work. You might have gotten lucky and bought pedals that work well with both instruments. That said, there are reasons why some work and some don’t.
01 Let’s look at this question from the perspective of the pedal, since it’s the bass signal that enters the pedal. Starting with signal strength, the average bass guitar has a peak voltage output of one volt peak-to-peak versus an electric guitar, which is around half that figure for humbuckers and a quarter of that figure for signal coils. Looking at those rough figures, you’d think that the bass guitar ‘overloads’ the pedal, but when we analyse the signal strength of active pickups in an electric guitar, they average around 1.25 volts, which is similar to a bass guitar’s output. An overly strong pickup output could overload a pedal with limited headroom; but this isn’t restricted to bass guitar.
The biggest difference between electric and bass guitar is the frequency range in which they operate. A four-string bass guitar operates in the range 40Hz to 400Hz with harmonics out to 4kHz. This is 30Hz to 525Hz for a six-string bass. An electric guitar operates around 80Hz to 1,200Hz with harmonics out to 5kHz. It is this expanded low-end that means a guitar pedal sometimes struggles. To optimise bass response, many guitar pedals do not focus the EQ of the pedal below 60Hz. This means that a large portion of a bass guitar’s signal would not be processed and passed through the pedal. For obvious reasons, this can make your bass guitar sound poor. Some pedals have a clean blend and, as such, they can effect higher bass frequencies and pass through the dry signal uneffected. These can work really well with both electric and bass guitar.
02 With all the above in mind, pedals that work well for both electric and bass guitar typically exhibit the following characteristics: 1) They have the ability to cope with an expanded range of low frequencies; 2) They have a clean blend option; 3) They have higher headroom, ie, the inputs can cope with stronger signals. Examples of pedals that work well for both include my own Fat General Compressor (reviewed on p120), Fallout Cloud Fuzz and Team Medic EQ. Also check out the Death By Audio Fuzz War, ElectroHarmonix Green Russian Big Muff, and Origin Effects’ SlideRIG Compact Deluxe.