Roles, Registers and the Frequency Ladder

A song is chords, melody and lyrics. An arrangement is who plays what, when, and where in the frequency spectrum. This is how demos become records.

The idea

Think of a band as jobs, not instruments.

Role	Who usually does it	What it provides
Foundation	Bass and kick drum	The low end, the roots, the rhythmic lock
Pulse	Drums, rhythm guitar or keyboard comping	The subdivision and the groove
Harmony bed	Rhythm guitar chords, piano, pads	The chords, sustained or rhythmic
Melody	Voice or lead instrument	The one thing listeners follow
Counter-melody and hooks	A second guitar, keys, backing vocals	Answers in the gaps of the melody
Ear candy	Anything	One-off details, transitions, textures

Any instrument can take any job, and jobs can move between sections. What matters is that every job is covered and that no two parts fight for the same one.

The frequency ladder. Every part needs its own zone.

Zone	Roughly	Who lives there
Low end	40–200 Hz	Kick and bass. Nothing else should be busy here.
Low mids	200–500 Hz	The body of guitars, piano left hand, low vocals. Mud collects here.
Mids	500 Hz – 2 kHz	Guitars, snare, vocals, piano. The most crowded zone.
Presence	2–5 kHz	Vocal clarity, pick attack, the “bite” of a lead guitar
Air	above 5 kHz	Cymbals, breath, shimmer

If piano and guitar both play full chords in the same octave, you get mud. The fixes are simple:

• Give the piano high voicings while the guitar plays low power chords, or the reverse.
• Use the small triads from Module 3 instead of six-string barre chords.
• Remove doubled notes. If the bass plays the root, the guitar does not need it.

One melody at a time. Two lead lines at once fight for attention. Counter-melodies go in the rests of the melody. This is call and response at the level of the whole band.

On your instrument

Guitar and piano together cover the whole range, which makes them the ideal pair for practicing arrangement.

• Split 1: guitar plays a low riff or power chords. Piano plays high, sparse triads and a counter-hook.
• Split 2: piano left hand plays the bass line and mid chords. Guitar, with a capo, plays high arpeggios.

With two guitars and no piano, do the same thing: one guitar low and rhythmic, one high and sparse. With only one guitar, record two tracks.

Worked example

An arrangement chart for a four-section song. Each row is a job and each column is a section.

Role	Verse 1	Pre-chorus	Chorus	Bridge
Foundation	Bass on roots, simple kick	Bass adds 8th notes	Bass and kick locked, driving	Bass drops out
Pulse	Closed hi-hat	Toms build	Open hi-hat, crashes	Ride cymbal only
Harmony bed	Guitar 1, palm-muted power chords	Guitar 1 opens up	Both guitars, full chords	Clean guitar arpeggios
Melody	Vocal, low	Vocal, rising	Vocal, high, doubled	Vocal, quiet
Counter	None	Guitar 2, one rising line	Guitar 2, octave hook between vocal lines	Piano, high single notes

Read across any row and the part changes at every boundary. Read down any column and every job is either covered or deliberately empty. No two sections have the same line-up. That is the whole method.

Exercises

1. Take Assignment Song 1. Write a one-page arrangement chart like the one above: for each section, list which roles are active and who covers them. Make sure no two sections have the same line-up.
2. Record a two-layer demo (a phone is fine): a rhythm guitar part and a second part in a different register. Then record a deliberately bad version where both share a register. Hear the mud. You will never unhear it.
3. Listen to a favorite record through one job at a time: only the bass for a whole song, then only the hi-hat and cymbals, then only what answers the vocal.

Common mistakes

• Everyone plays all the time. If every instrument is in from bar 1, the song cannot grow.
• Two guitars playing the same thing in the same place. Double a part on purpose, for thickness. Do not do it because nobody wrote a second part.
• Fixing arrangement problems in the mix. If two parts mask each other, change the parts.