Music changes over time. This is a constant, reliable fact that is clearly evident just from listening to any two songs from any two different eras. Changes in musical influences and tastes means that demands on effects and amplification also inevitably change alongside music. Certain sounds and tones come and go out of fashion over time, and so effects and amplifier companies often have to be aware of changes in taste.
While the guitar tone, effects and tube amps are usually considered a benchmark, and are often sought after by musicians, certain genres require effects pedals with specific characteristics. With distortion pedals – the most obvious example – certain kinds of music may require greater or reduced string to string definition, heavier or lighter clipping or darker or lighter tones.
A lot of blues music for example might be characterized as requiring darker, lightly clipped distorted tones with little emphasis on individual string definition. Speed metal is almost completely opposite, needing the mids and highs as well as plenty of definition, so that fast solo lines shine out from the general mix of the band when they need to.
The idea of string to string definition is one thing which is slightly less considered, and often even completely overlooked. Distortion effects by their very nature have a tendency to ‘muddy’ the sound, blending notes in chords together into one general sound. That being said, not all music which makes use of distorted tones will necessarily require this kind of ‘wall of sound’ clipping. Certain rock songs, and this is usually pretty true of progressive rock music, will require both the harder distortion and the defined individual tones. A good distortion pedal will deal with every string and every tone well, even when there are many sounding out at the same time. For example:
See? Pedals with good string to string definition will allow chords to cut through beautifully, and tastefully, as they should. They will add to the tone of the guitar, without detracting from the playing of the guitarist. These kinds of distortion pedals are incredibly useful for many rock guitarists, and they are also regrettably few and far between. On the other hand, if droning guitar distortion is more your thing, there’re plenty of pedals for that too!