Harmonics on Sub Bass

Why Add Harmonics to Sub Bass?

Small speakers, like those found in a notebook computer or smartphone cannot properly represent very low frequency material. Programme material that features a lot of sub bass instrumentation will most likely sound thin and sparse when referenced on these types of speakers. Adding additional harmonics to the sub bass parts will help.


Introduce a small amount of distortion using an aux send on your DAW or mixing desk to add related frequency content above the fundamental sub bass tone. Doing this will appear to make the original sub bass part audible on tiny speakers by tricking your ears into hearing something that may not actually be present. Remember that subtlety is key, so even percent or two of distortion will help.

Advanced Technique

Add an equalizer or filter after the distortion and experiment with filtering out the high, low or mid frequencies of the distorted signal to add interesting sonic character. Different forms of distortion, like analogue distortion from transistors, tape and vacuum tubes or even digital clipping will also yield different and interesting harmonic texture. Choose the one that best suits your programme material.


Awesome sounding plug-ins for this technique are SoundToys Decapitator, Waves NLS or Camel Audio CamelCrusher. However, in my opinion, the ultimate tool for this is the Thermionic Culture Vulture.


The High Pass Filter

What is a High Pass Filter?

A high pass filter (sometimes called a low cut filter) allows high-frequency signals to pass unchanged, but reduces the amplitude of signals lower than the cutoff frequency. The amount of attenuation is defined by the slope. Using a high pass filter on parts can help focus a song’s low end by only allowing the most important low end sounds to exist in the mix.


To start, decide what part or parts of the song should provide the sub bass frequencies. This would usually be the kick drum and bass synth or bass guitar. Use a high pass filter on all the parts of your mix except those. Start at approximately 80Hz, then sweep up slowly until you start to hear the sound change and then turn in back down slightly. Experiment with different slopes; with 6db/Oct sounding more gentle and “natural” and on the other extreme; 48db/Oct sounding modern and “digital”.

Advanced Technique

Advanced mixers should experiment with a resonant high pass filter on parts to make it poke out. Somewhere between a Q of 1 and 1.4 should be all that is needed, but higher Qs could yield interesting results, too. A resonant high pass filter can even be used on sub bass parts like bass or kick drum to make them really stick out. This is how the famous Little Labs Voice of God works.


My all-time favourite high pass filter is FabFilter Pro Q. The second generation of this plug-in was recently released and it sounds amazing. For producers just starting out, I suggest checking out iZotope Alloy. It packs a great EQ, Compressor and more in a single plug-in so you only have to learn one GUI. Alloy is both quite musical and a good value.


Preparing Your Project for Stem Mastering

Stem mastering is ideal for those who have problems getting their mix to sound the way they want or just wish our help in perfecting it. Stems also allow for Out-of-the-Box summing, which can give a more clear and open analogue sound. The steps for getting your songs ready for Stem Mastering are mostly the same as stereo mastering. We recommend you review this article before reading further. The main differences are outlined below.

Make stems

A stem is a collection of similar tracks that have been mix down together in your DAW as a stereo audio file. The level of each instrument in a particular stem should be as close as possible to the desired volume of that instrument in the final mix. However, stems do give more room for us to fine tune those levels. Our standard for stem allocation is as follows:

  1. DRUM – kick and snare drums
  2. PERC – the remaining percussion such as hi-hats, crashes, hand drums, etc
  3. BASS – whatever instruments are playing the bass part of the song
  4. INST1 – the primary or most important instruments
  5. INST2 – the remaining instruments, special effects, risers, etc
  6. VOX – lead vocals or most important samples
  7. BGVOX – background vocals, less important samples
  8. FX – reverbs or delays, etc

If we need any tracks broken out from these stems, we will request it and not charge you for the additional stems.

Leave headroom

None of the meters on any of the stem channels should exceed -8 dBFS. Some channels, such as FX, may peak much lower.

Organize it

Please organize your project before sending it to us. Create a folder and name it after the overall project. Then create folders inside it for every individual song naming them after each song. Place all the stems with both the song name and stem name in it. You can include any reference versions in the folder for the song.

You can then Zip up the parent folder and proceed to the order page because you are ready to go. As always, feel free to contact us if you have any questions about our services.


Preparing Your Project for Mastering

You’ve done it. You finished mixing your new project and gotten past a point that many artists have trouble getting to. We are happy that you’ve made the decision to get it professionally mastered and chosen our Mastering Service to do it. Below are the last steps before sending them to us for mastering.

Make sure its ready

Be sure your song’s composition and the level of the individual instruments are the way you want them. If you are not sure about your mix, we offer a free Mix Analysis with every paid project. If you want more help, we suggest you look at our Stem Mastering service, which gives us great flexibility with this. Don’t worry about matching the volume of commercial releases, we’ll take care of that.

Leave headroom

Your final bounce should have between 6 and 12 dB of peak headroom. Another way of saying this is make sure the peak meters on your master channel are hitting between -12 dBFS & -6 dBFS. If your songs does not, pull down each channel fader a few dB (by the same amount) until your song falls into in that range.

Bypass buss processors

If you have any buss processors such as compressors or limiters on your mix buss, disable them. If a compressor or limiter is vital to the sound of your track, do a separate bounce with it enabled and label that bounce as a reference track so we can match the vibe.

Keep your settings

To achieve the cleanest audio possible, avoid any sample rate conversion or bit depth quantization when mixing down your songs. Keep the same sample rate and bit depth as your song’s project file. For example if your DAW is set to a 88.2 kHz sample rate and a bit depth of 32-bit float for a particular song, bounce it at that setting.

Don’t dither

Noise Shaping & dithering technologies mask the distortion caused by quantizing from higher to lower bit depths by introducing small amounts noise. Since this process adds noise, it should only be done once per song and at the end of the mastering process. Finding most appropriate variation of noise shaping for the particular song is part of our mastering process.

Don’t normalize

Remember that we request between 6 and 12 dB of peak headroom? Enabling normalize would lose this headroom.

Check it on headphones

If at all possible, listen to the final mix of your song (the one you are about to submit for mastering) on a pair of decent headphones and make sure there are no pops or clicks that are not supposed to be there. If there are, figure out what is causing the sound and fix it. Some of the causes of those unwanted sounds are:

  • Clipped audio – check for any of your clipping indicators in your DAW (have you left enough headroom?)
  • Recorded chair creaks or foot taps – can you do an edit or re-record the part?
  • Slow processor or disk – if your DAW has a freeze function, enable it or increase your DAW’s buffer sizes (or do both)

If there are unwanted sounds that you are unable to remove take note of the time they appear in the song and let us know in the project notes. We will see if we can fix it for you.

Organize it

If you are sending us more than one song, please organize your project before sending it to us. Create a folder and name it after the overall project. Then create folders inside it for every individual song naming them after each song. You can include any reference versions in the folder for the song.

Zip it

Once you have your project organized neatly into folders, create an ZIP file of the whole project folder. If you prefer RARs, go ahead and use that. We are not as concerned here with reducing the file size, but compressing your project creates an easy check to make sure none of the data was corrupted during the transfer to our studio.

Once you’ve done all these steps, you’re ready to go. Drop by our order page and we’ll get started on your mastering.