If you are using a passive instrument, such as a guitar or passive bass, a buffer is arguably one of the most important pedals to get a good sound.
Passive instruments typically provide a high-impedance output. This means that; as the length of the cable(s) between your guitar & amp increases, your tone quality decreases. Typically; if you have a very long cable or run a lot of true-bypass pedals, you lose some of your high frequencies and get a warmer sound; losing your brightness.
This may be desirable for some musicians targeting a vintage tone. However; most of us would like to preserve the original tone of the guitar and make purposeful adjustments on the amp.
It is easy to test if you have such a problem.
- Insert your guitar directly into your amp with a short cable, and listen.
- Run your guitar through your pedals (turned off), and listen.
If you hear audio degradation, your signal path is sucking your tone off.
That’s where the buffer steps in. A typical buffer will transform your high-impedance signal to a low-impedance signal; which travels relatively effortless among pedals and long cables, reaching the amp without dramatic losses. Thus, you end up hearing the original tone of your guitar; preserving the high frequencies.
Playing passive basses, I put the buffer at the beginning of my signal chain. That way, my tone doesn’t get dimed by following pedals. Typical active instruments provide low-impedance signals and don’t really need an “opener” buffer.
If I have a long pedal chain, I might also place a buffer at the end of the chain to re-vitalize my tone before it hits the (long) cable reaching to the amp/desk.
A buffer will typically have a high impedance input (1MΩ) and a low impedance output (<1KΩ). If you have an always-on pedal (such as a compressor) or a pedal with buffered bypass with similar values, that pedal would be buffering your signal anyway. Using an additional buffer could be obsolete at that point.
Be warned though: “Too much buffer” is as real as “signal degradation”. Using too many true-bypass pedals or long cables can make your tone muddy, that’s true. On the other hand; using too many buffers or buffered pedals can make your tone harsh and thin – which is equally undesirable for many.
Therefore, you need to pick your pedals mindfully – keeping your signal impedance in mind as much as your creative tonality.
- For small boards, one buffer should be enough.
- For medium boards, one buffer towards the beginning and one towards the end should be enough.
- For large boards, you might need additional buffer(s) in-between.