5. Low-end control: notes that weigh differently

When one note of the riff explodes and another disappears: multiband compression, dynamic EQ and kick sidechain (and when you need none of it).

There’s a problem a regular compressor doesn’t solve: some notes weighing far more than others, not in overall volume but in low end. You play the riff with the same force and the G sounds normal while the E shakes the room. This section is for that — and it starts with a warning: you may not need it.

Why it happens

Two reasons that add up:

The note lands where it lands. Each note has its fundamental at a different frequency, and your chain (bass, amp sim, EQ) isn’t flat: if your curve has a boost at 80 Hz, the note whose fundamental lands there will sound twice as fat.
The room you listen in. Every small room reinforces and cancels low frequencies depending on position. Sometimes the note doesn’t really “explode”: it explodes in your room. That’s why it’s worth confirming the symptom on headphones before going out to fix it.

Tool 1 — multiband compression

This is the direct answer: compressing only the low band, leaving the mids and the attack intact.

Multiband Dynamics

Multiband compressorstock Studio One Pro 4

Studio One's stock multiband compressor. Compresses the lows without touching the mids: the tool for making every bass note weigh the same.

Multiband Dynamics splits the signal into frequency bands and compresses each one separately. On bass it solves a problem a regular compressor can’t: some notes sounding far bigger than others.

The problem it solves

A bass is not even by nature. Depending on the note, the fundamental lands in a different part of the spectrum, and on top of that the room you record in reinforces some frequencies. The result: two notes played with the same force, one sounding twice as fat as the other. A regular compressor, seeing a low peak, compresses the whole bass: it also pulls down the mids and the attack, and the instrument “breathes” oddly. The multiband pulls down only the lows of that note and leaves the attack intact.

How it’s used on bass

Low band (up to ~150 Hz): the one doing the real work. Firm compression here evens out the weight of every note.
Mid band: at rest or very gentle. This is where the bass’s intelligibility lives; compressing it too much dulls the instrument.
High band: normally untouched.

Where you’ll use it

In mixing, on the bass track or bus, after the corrective EQ. It’s also the emergency tool when a single note of the riff “explodes” and you don’t want to pull down the whole instrument because of it. If you don’t need it, don’t insert it: it’s easier to ruin than a regular compressor.

Alternatives (for reference)

TDR Nova (free, 4-band dynamic EQ)
FabFilter Pro-MB (the multiband reference)
Fat Channel XT with the compression module (also stock)

Captura de Multiband Dynamics (de tu Studio One Pro 4)Pending — this one is on you

The Multiband Dynamics open on the bass bus, with the low band (below ~150 Hz) compressing and the rest of the spectrum at rest. The crossover points between bands and the gain reduction meter of each band should be visible.

Formato: PNG o JPG, legible (que se lean los valores). Dejala en prodmus_frontend/public/img/plugins/ y avisame para integrarla y validarla.

Low band (up to ~150 Hz)threshold for 3–5 dB of reduction on the notes that explode

This is the band doing the work: it pulls down the excess weight of the problem notes and leaves the others as they are. Because it only acts down low, the pick attack and the presence are untouched — which is exactly what a regular compressor can't do.

Mid bandat rest or very gentle

This is where the bass's intelligibility lives (the harmonics from the previous section). Compressing it too much dulls the instrument and undoes the work of making it audible.

Tool 2 — dynamic EQ

A dynamic EQ is a cut that only acts when the frequency shows up. If the problem is one very specific zone (a peak at 95 Hz that jumps on two notes of the riff, say), it’s more surgical than the multiband: the rest of the time the bass is untouched.

Tool 3 — kick sidechain

Sidechain makes the bass dip slightly every time the kick hits: the kick finds free space at the exact moment it lands, and the bass comes right back.

When yes and when no

It helps if you have a very fast kick (double pedal) and, despite your EQ sharing, the kick still gets lost. 1–2 dB of well-set ducking unblocks that situation.

It doesn’t help as a replacement for the frequency sharing in section 2. Audible sidechain pumping is distracting if you use it heavily, and in rock/metal it’s rarely needed: it’s a far more central tool in electronic music.

🔵 Can wait· in mixing

These are fixes for specific symptoms. Sharing with the kick, compression and saturation solve 90% of cases; this is for the remaining 10%. If you don't detect the symptom, don't touch anything: on bass, every extra plugin is a way to dull the instrument.

Before using any of the three: clip gain

Worth repeating because it’s what pays off most. If the problem is two or three specific notes, pulling them down with clip gain is faster, more transparent and more precise than any dynamic plugin. Multibands and dynamic EQs are for when the problem shows up many times and in different places.

Common mistakes

What you should NOT chase yet

Quick route — only if you have the symptom

Quick path

Confirm the problem on headphones (it may be your room).
Is it two or three notes? Clip gain and you're done.
Is it systematic? Multiband Dynamics: compress only the band up to ~150 Hz, 3–5 dB on the notes that explode.
Leave the mid band nearly at rest.
Only if the kick still gets lost with a double pedal: 1–2 dB of sidechain.
Compare against bypass at matched volume: it should sound more stable, not duller.

Expected result

A low-end stable bass: no note of the riff shakes the room while another disappears, and the kick keeps its place even in the fastest passages. If you got here and didn’t need to touch anything, that’s a valid result too — it means the previous sections did their job. Last step of the mix: integrating the bass with the guitars.