After a long career in this industry, I have made a few friends in all areas of engineering. One mastering engineer posted recently stating the one of the most common issues he faces is uncontrolled lowend from bass guitars and subharmonic frequencies, usually from inexperience or lack of monitoring to even hear them. I can’t give everyone a subwoofer otherwise I really would! But in the meantime I can impart some wisdom in yet another blog post, but today’s topic focuses on how to control and add groove into your bass. Let's dive in!
Compression For 2 Purposes
Compression can serve two carefully adjusted purposes with bass guitar especially. Not only can we control the low end but we can also shape the sound to help the flow and feel of the song move more.
Most compressors will have a high pass function that is extremely handy when you feel the signal is pumping or misbehaving in some way. Moving this up to around 60-80hz can let a lot more low end pass untouched by the compressor and you retain more focus on that lower part of the body of the guitar and amp tone. There are several way to approach bass compression, by adding more punch and attack, or leveling the signal if you have an inconsistent or novice bass player for example, but I find the most exciting is to stay with an attack time of 10ms or above, and adjust the release to taste for the track - the shorter the release, he more aggressive, the longer the release, the more controlled and the compressor will ride the bass signal. Just becauseful you don’t add more dynamics and pumping by choosing an attack time that doesn’t work with the speed at which the bass is being compressed - it’s a bit of trial and error but these tips will give you a great start.
Now, as we’ve discussed, compressors are very different from one to the next - from makeup components, to age and everything in between. But this is also a benefit as it can help add more groove into the playing. Take for example the LA2A, it’s medium attack and slower release as well as being fixed control (no ability to change the attack and release settings) means you have a one stop shop compressor that you can dial the high pass function to taste. And when really pushed, it gives a certain flavor and groove that can’t really be replicated that works really well for slower songs.
The LA-2A has been replicated in plugin form time and time again, the UA version being very close to the original warm, musical tube sound loved by engineers
The DBX 165 however is a VCA compressor with a much faster attack and release, and even when set in auto mode which it’s famed for as it changes it’s settings automatically via a signal dependant circuit; when put on the same signal, it will sound much more aggressive and imparts a growl that won’t be available on smoother, more transparent compressors such as the LA2A we touched on above. Even the limit functions on both will be totally different, the DBX is a very aggressive compressor that, when the limit is engaged, can add prominent clipping and distortion that can really bring out a rock bass guitar for example, whereas the LA2A will add more punch, but more more depth into the lower end of the signal with a smooth harmonic distortion due to the valve driven compression.
With both of these compressor and any others you might experiment with as well, don't be afraid to 'pin the needle' and reduce by as far as the needle will go. To impart the sound characteristics of the compressor, invariably you need to be extreme to get the best results (the mix knob is your best friend here to dial in the compression to taste!).
The SixtyFive is a faithful recreation of the dbx 165 and is also free! Go try it on bass guitar and tell us how you found it.
Sidechain and Multiband Compression in Unison
We’ve talked about this exact topic in another post, but I briefly wanted to remind how useful it can be for taming low end. As we’ve talked about already, the high pass function can be engaged to help retain a low impact and tame the rest of the bass signal - but that also leaves the loweven untouched and still out of focus and wild, left to its own devices.
Multi-band compression from 80-120hz and below can really help here. It’s almost set and forget, simply add the compressor of your choice, set the band from the lowest point to 200hz or to taste, and as a good starting point, set the attack at 30ms and decrease for more control however remember you’ll sacrifice bass as well (I sometimes will set the attack as low as 5ms, and compensate in makeup gain or adding a Pultec style EQ to enhance the lower end again in a much more musical way!). Set the release to around 120ms which is relatively medium, and try to only reduce by around -4db, but always remember to gain match as you go. A/B’ing between a before and after processing is important here, it’ll help you decide whether you’d help the track or starting to make it flat and unexciting.
The Ambisonic Multiband Compressor is a great free alternative for new and veteran engineers if stock plugins aren't cutting it, or you fancy something new!
Lastly, try sidechaining the Kick to the Bass guitar with another band in your multi-band compressor set to the external input setting on that one band, and adjust the setting to be a fast attack and release (10ms and 50ms release works well for me usually), and allow the kick to trigger the compressor, reducing by the same about as above but this time, try to not compensate the level and let the kick sit in that part of your mix for a split second as it’s kick. This doesn't work for every track, but it greats a clear separation in your low end marriage and helps the instruments live cohesively and in harmony with each other.