Spectral analysers are bundled with most top DAWs now. This often overlooked metering tool is key to achieving the best possible sound you can. Of course, a visual representation of your music is substitute for your ears and trusted monitoring systems but using it conjunction with these can iron out frequencies that are letting your mix down and might go undetected.
So what is spectral analysis? It’s simply a graph mapping frequency (x-axis) against volume (y-axis), and this changes over time as your track is played. A spectralnsare analyser can be placed anywhere in the plugin-chain, but ordinarily at the end makes most sense. Placing it on your master channel is going to give you the most flexibility as you can solo a sound/group of sounds if you need to check those. (It’s also worth noting that if you have any limiting/mastering plugins in your master channel strip to put the analyser after these, to ensure you’re viewing the limited sound).
Logic, Ableton and Reason all come bundled with spectral analyser tools, but for this I want to look at Voxengo SPAN. It’s free, comes in AU and VST format and (importantly) is 64-bit compatible (alternatively, another free option is Blue Cat’s FreqAnalyst). To get going with spectral analysis, it’s necessary to understand a little about frequency, and what you’d typically expect to hear where. To the left are lower sounds and to the right are higher sounds, so that’s sub-bass, kick drums, bass guitar and such to the left, all sorts of cymbals, white noise* risers, distorted sounds to the right. In the middle is everything else.
*It’s worth noting that true white noise is every frequency present at the sample amplitude, but typically people associate it with the higher end ‘fizzle’.
This guide made by Future Music shows roughly where you’d expect to hear drum sounds in electronic music. Knowing where your sounds should sit in relationship to each other is key to getting a balanced sound. As you can see, lots of sounds have the potential to overlap and allowing each sound space to breathe is going to give you more clarity and headroom when mixing. Practically, this means you might need to be surgical with EQing and careful about which sounds overlap, the stereo image and reverb. All of these factors will determine how your overall sound is perceived. A sound in solo might sound great, but in context it could be muddy/distracting.
I’m going to look at four different kick drums, all from the Sample Magic Vintage House sample pack. All of them have different characteristics:
Kick 1 has a beefy low-end, with the fundamental (strongest note) sitting around 50-60 Hz. Note there are also peaks in and around 2-8k Hz, which is where the sounds prominent ‘punch’ comes from. This is a complete sounding kick, with the right low-end and snap ratio.
This kick has a similar fundamental but less sub content below it, and there’s also a more noticeable peak at 150 Hz. There’s presence around 2-8 kHz region too, but it’s far busier and cluttered. There’s also a sharp tail-off in the extreme high-end (18-19 kHz). This is a hollower, roomier kick than the first example, probably lifted from a recorded kit rather than a drum machine or sampler.
Similarly to kick 2, there’s an abrasive high-mid frequency grouping. The tail-off is less harsh than kick 2, and scooping in the mid-range (300-800 Hz) is less obvious too. This kick sounds layered to me, it has a low-end similar to a drum machine but the top end is likely from a breakbeat or similar.
Finally, kick 4 is the subbiest of the four, with the fundamental falling in pitch more audibly and with? less high-end content. The sound is almost non-existent past 6 kHz. This kick is probably from a TR-808 or emulation of it.