We all like great sounding bass, right ? We all agree on that, however a number of producers and engineers have some difficulty in getting the low end frequencies in an audio mix to sound just right. This is going to include your kick drum and your bass line. Getting these instruments to marry nicely can be hard work and these top tips will definitely help you improve the sound of your tracks low end.
1) Choice of sounds, if from the very outset you are hearing that the bass and kick are not marrying together in the way you want consider a completely different synth bass patch and/or swapping out your kick drum sample. There is no point making life difficult and this could save you a lot of head scratching from the get go.
2) Your bass line and kick drum will comprise of a fundamental frequency and harmonics (unless you are using a sine wave bass). Experiment with the pitch of the kick drum if it is not working well with the notes in the bass line. It is remarkable how powerful an effect changing the kick drums pitch up or down a few cents can be in getting it to work nicely with your bass. If the fundamental in the kick is close to one of the notes in the bass it can cause problems when they play together.
3) Monitoring is extremely important, without sonic accuracy there is no basis for action. If you cannot hear what is actually happening in the bottom end you are simply guessing. Taking the guess work out is fundamental and this means understanding your monitors deficiencies well enough to overcome them or bettering your monitoring situation. Also ensure that you are monitoring at around 85dB SPL for at least part of the mixing session, this is the level at which the ears natural response flattens. Read up on the “Fletcher Munson equal loudness contours” for more detail.
One trick you can use is to temporarily stuff the bass reflex port on your speakers with a small towel or foam wedge to gauge the bottom end with a sealed enclosure. Sealed enclosures often provide a more accurate bass response than a reflex design. You might hear deeper lows with a reflex port but it skews the flatness of the low end roll off making it more difficult to judge instruments that co-exist in the bass department. Do not keep active speaker ports stuffed too long as the port may dissipate heat from the internal amplifier.
Install bass traps, no way around, it unless you have bass traps your in room monitoring the low end at any useful volume will be inaccurate. Bass traps absorb the the low frequency energy as it hits the room boundaries such as corners and walls. By stopping the waves reflecting back to your ears where you are monitoring you are increasing the accuracy of the monitors and room. The waves reflect and combine with the originating waves and cause a total mess of the low end. Broadband bass traps are best made from Owens Corning (USA) or Rockwool RW3 (Europe). Observe local safety guidelines when handling these materials.
4) Equalization and high pass filters can assist greatly. If you do not have full range monitors try and get a pair of good quality headphones that have a decent deep bass response. There is no preset suggestions for equalization or using a HPF. But the goal with using a high pass filter is to try and remove the deepest lows which are not adding punch or depth or musical information to the bass. Often we are speaking about frequencies that are below 35Hz. A high pass filter can be used on both the kick and bass line if need be. Care must be taken to set them up effectively so you keep the sub bass elements you want and clear out the infra sound you don’t. Equalization of notes can be effective (as can MIDI note velocity) for balancing out the bass notes if some of them unintentionally sound louder than others. When it comes to kick drums consider the attack portion of the sounds not just the low end. The attack is responsible for some of the kick drums punch and is often in the 2-5kHz part of the spectrum. Sweep an eq around over kick (2-5kHz) till you find the sweet spot between mid range attack and low end bass weight.
5) It is possible to create a hole in your bass line to let the attack of the kick drum punch through. The technique is called side chain compression. You apply a compressor to your bass line track in your DAW. Select the compressor with care as it needs to have a side chain facility. This means the compressor can sit on a track (bass) and yet be controlled by another sound source in your mix (kick). In this case you need to route the kick drum into the side chain of the compressor as a trigger. As the bass line passes through the compressor the goal is to get the kick drum to slightly “duck” or attenuate the bass line by 1 or 2dB when the kick drum hits. This small dipping of the bass line allows the kick drum to sound more powerful and can add rhythmical drive to you track.
The above techniques will help you get your low end defined, translating well across all the different sound systems it will meet. It will help your bas line and kick be well balanced and keep the low end punch required of a good mix down.
Barry Gardner operates SafeandSound mastering a low cost, high end mastering studio based in London UK. Visit the site today: http://www.masteringmastering.co.uk/cheapmastering.html