The bass guitar is glue that holds the band together.
I have no idea what this analogy means. I’ve heard it said about bass – and almost everything else on stage – and I cringe every time I hear it! But, I shouldn’t complain without an alternative, so I’ll offer my own view of how the bass functions in pop/rock music:
The bass guitar bridges the percussive and harmonic elements of a song.
As percussive instrument the bass plays a steady groove, closely tied to the drum kit. It can produce big pulses of sound all way down to the lowest frequencies, so when the bass locks into a groove it tends to define it. Bass is also just about the most effective instrument for playing short and long rhythmic pulses. Think about it! Drums can’t play long pulses and the bass generates more sheer acoustical energy than any other instrument that can! A great example of a bass line with short and long pulses is “Tempted” by Squeeze. The bass tends toward short on-beats and long off-beats which creates a groove full of tension and release.
As a harmonic instrument, the bass stands apart from drums because it plays real notes! Its habit of playing the root note of each chord helps anchor the harmonic content of a song. Sometimes the bass is the only instrument playing the root! Take “With Or Without You” by U2 for example. The guitars are playing single note lines, nothing else is playing chords, and yet we can identify the implied chord progression from the root notes in the bass line.
If you have a hard time picking out the bass in a recording, look for it in these two places: locked in with the drums (percussive), and at the bottom of the chord structure (harmonic).
Let’s move on to how it sounds. For now, I’ll identify three essential sounds in the timbre of the bass guitar: the “rumble”, the “warmth” and the “attack”.
The “rumble” is the low end of this already low instrument – the bass of the bass. These are the frequencies you feel more than you hear, the ones that hit you in the gut and make you want to move to the groove! A standar four-string bass guitar can produce a fundamental frequency around 40 Hz and a low B on a five-string is down near 30 Hz! Most of the low frequency energy, however, finds its centre between 50-100 Hz.
The “warmth” of a bass guitar is still in the low end, in the neighbourhood of 250-400 Hz. It’s not the power range, but it helps to give the bass a rounder or softer sound. Recordings with a more classic sound often feature a “warm” sounding bass with lots of character in this range. A spot-on example is Pino Palladino’s bass on John Mayer’s “Continuum” album.
The “attack” refers to the sound of fingers or a pick plucking the strings. It’s similar to the attack of a stick or beater striking a drum and is found in the speech intelligibility range, most likely between 1-4 kHz. This sound gives us the exact timing of the bass notes, which is difficult to distinguish with just low frequencies. A bass with no “attack” or “finger sound” sounds washy and lacks definition, especially in a live environment where you have less control to begin with.
Okay, so what about this elusive “growl” everyone talks about?
The “growl” quite literally sounds like an angry jungle cat, specifically the midrange or telephone frequencies in that sound. Sit down with a good recording and try to imagine the bass guitar is talking to you. If you can do it, you’re probably focused on the “growl” in its tone!
(Now go see your therapist, I’m worried about your sanity!)
The right sound always starts at the source, and bass is no exception. If a bass doesn’t have any growl to begin with, you will not be able to add it at the sound console! The instrument and the player are the crucial factors. It’s also not uncommon to add in a little overdrive or distortion. In this case, the bass takes on some of the character of an electric guitar. Perhaps the most sought-after example of overdriven bass “growl” is “Roundabout” from the album Fragile by Yes. How exactly Chris Squire acheived that perfectly overdriven sound back in 1972 is still hotly debated in online forums.
Today, Dubstep’s wobble bass or “wub” is the new standard for bass (if you haven’t the sweetest clue what dubstep is, check out “Feel So Close (Nero Remix)” by Calvin Harris … and don’t blame the messenger!) This popular club style features very aggressive bass tones with distortion, sweeping envelope filters and all kinds of stuff. They’re synthesized sounds, not a real bass guitar, but they show the extent to which modern music is pushing the limits of this low-end lion.
So if you have subs, turn them on! If you have big headphones, wear them! The bass is a real team player, often overlooked, but absolutely essential. Just like … say … glue that holds things together (if you like that analogy).