You searched for how to mix sub bass, so one of two things is happening: the sub sounds huge in your headphones and then vanishes on a laptop or phone, or it is technically there and you have no idea whether the level is right. Both problems share a root. Sub bass lives in a range most rooms and headphones misreport and small speakers physically cannot play, so you end up mixing the most powerful octave of your track by guesswork. This guide replaces the guesswork with numbers: the exact range the sub occupies, how loud it should sit against the kick, and the harmonic trick that makes it audible on a phone speaker.
Where sub bass lives, and why your room lies about it
The fundamentals of a sub bassline sit between roughly 30 and 60 Hz. E1 is 41 Hz, A1 is 55 Hz, and most basslines in electronic music move within an octave of those notes. That range is exactly where monitoring falls apart. An untreated room builds standing waves below 100 Hz, so a 50 Hz note booms at your chair and disappears two steps to the left. Consumer headphones either roll off below 40 Hz or hype 60 to 100 Hz to fake depth, which makes you cut the real sub. And a laptop or phone driver gives up entirely below 100 to 200 Hz, so nothing you put at 45 Hz reaches that listener at all.
The consequence: you cannot mix sub bass purely by ear in a bedroom setup. You need an analyzer, a reference track, and the translation moves below.
Keep it simple: one mono sine below 120 Hz
A sub that translates is boring by design. Use a single sine or triangle oscillator as the core, because anything with more harmonic content turns into uncontrolled energy across the whole low end. Keep everything below 120 Hz dead mono. Stereo content down there cancels unpredictably on club systems that sum the low end to one driver, so put a utility plugin after the sub and force mono below 120 Hz. That also means no chorus, no unison detune, and no stereo wideners anywhere on the sub channel. If you want width, add it to a higher layer, never to the fundamental.
When you layer a second oscillator or a sampled sub on top, watch phase. Two layers playing the same note slightly out of phase can cancel 6 dB or more of your low end while both meters read fine. Flip the polarity of the new layer and keep whichever position sounds fuller, then nudge the sample start until the waveforms align. One clean layer beats three smeared ones every time.
Level the sub by numbers, not by feel
Setting the sub level by ear in a room you cannot trust is how mixes end up 6 dB off in either direction. Set it against a released track instead. Pick a commercial reference in your genre, loudness-match it to your mix, and put a spectrum analyzer on both. Compare the 30 to 60 Hz region directly: your curve should land within 1 to 2 dB of the reference, not just look vaguely similar.
The relationship to the kick is the number that matters most. In bass music, meaning drum and bass, dubstep, and trap, the bassline is the lead instrument and the sub typically sits 3 to 6 dB above the kick in the sub region, with the kick punching through at 60 to 100 Hz instead. In four-on-the-floor genres like techno and house, the kick owns the bottom and the sub tucks in below it in level. The deciding factor is which element carries the groove: if the bassline is the hook, it wins the sub region; if the kick drives the track, the kick does. The handover itself, who owns which octave and how to sidechain the seam, is covered in full in the kick and bass guide. And if you want this measured instead of eyeballed, upload your track to TrackSensei and it compares your low-end balance against released tracks in your genre, in dB.
Harmonics make sub bass audible on small speakers
This is the fix for when you cannot hear sub bass on anything small. A phone speaker will never reproduce a 55 Hz fundamental. What it can play is the harmonic series stacked on top, and saturation is how you build one: the 2nd, 3rd, and 4th harmonics of a 55 Hz note land at 110, 165, and 220 Hz, high enough that even a tiny driver reproduces most of the series. The listener's brain hears those harmonics and reconstructs the missing fundamental, so the bassline reads as deep even when the actual sub is gone.
Do it in parallel so you keep the clean fundamental. Duplicate the sub or send it to a bus, drive that copy hard into a saturator or tube emulation, high-pass the saturated copy around 80 Hz, and blend it in 6 to 10 dB under the dry sub. Alternatively, design a dedicated upper bass layer that lives at 80 to 250 Hz and plays the same notes. Genres built on bass weight rely on this constantly; the drum and bass production and mixing guide treats the sub and its midrange counterpart as two halves of one instrument for exactly this reason.
Compress 2 to 4 dB so every note holds the same weight
Sub energy is brutally unforgiving of level differences. A note that plays 2 dB hotter than its neighbors eats your headroom and pumps the whole mix; a note 2 dB quieter leaves a hole the listener feels in their chest. Put a compressor on the sub channel with a ratio of 4:1, a 10 to 30 ms attack, and a release timed so the meter resets between notes, then aim for 2 to 4 dB of gain reduction on the loud notes. The goal is every note holding the same weight, not audible squash.
Then sidechain the sub to the kick. Even with a clean spectral handover, both hitting at once costs headroom. Trigger 3 to 6 dB of ducking from the kick with a release short enough that the sub is back at full level before the next hit. At 174 BPM drum and bass that means a release under 100 ms; at 125 BPM house you have more room.
Tune it: an off-key low end reads as mud, not pitch
Below about 40 Hz, pitch perception fades and the ear hears pressure instead of notes. That has two consequences. First, the sub must follow the key of the track exactly, because an off-key sub does not register as a wrong note, it registers as mud that no EQ can find. Check that your sub patch is tuned to concert pitch and that any sampled sub is pitched to the project key, not just close. Second, keep your fundamentals above E1 at 41 Hz whenever the key allows. A bassline riding at 30 Hz wastes enormous headroom on energy almost nobody perceives as pitch. If the key drags notes below that, play them an octave up and let the sub patch supply the weight.
Verify in mono, on a phone, and against a reference
Three checks confirm the sub before you bounce. Collapse the mix to mono: if the low end drops in level, a stereo or phase problem survived and needs fixing at the source. Play the bounce on your actual phone: you should clearly follow the bassline melody through the harmonics even though the fundamental is gone. If you cannot, the saturation layer needs more level or drive. Then A/B against your reference at matched loudness, because an unmatched comparison always flatters the louder file; the master loudness guide explains how to match LUFS so the comparison is honest.
Every one of these checks fights the same enemy: a monitoring chain that misreports everything below 60 Hz. If you want the verdict in numbers instead of another educated guess, upload a bounce to TrackSensei and read the low-end section of the report. It measures your sub level and kick balance against masters that already work on real systems and tells you, in dB, whether the sub is actually 4 dB hot or whether your headphones have been lying about it the whole time.