Gotta love acronyms. NES, Nintendo Entertainment System. PSG, Programmable Sound Generator. WTF, I think you get the picture!
OK retro fans I was asked an interesting question the other day about how synthesis was used in the soundtrack for Warfire and when answering I came to a realisation that it hadn’t been used at all (thanks Tim for the curly question!). To solve this blazing omission I was inspired to do my take on an NES sounding version of the main theme that used sounds typically found on an NES soundtrack. The first step was to find out how and why the NES made the sound it did, a task that was simplified from a great piece of reference material, Game Sound by Karen Collins (2008, Massachusetts Institute of Technology). Collins describes the NES’s sound chip in detail (p.25) and informs us that it was a custom built five-channel PSG chip designed by composer Yukio Kaneoka. The channels were; two pulse-wave channels, a triangle-wave channel, a noise channel (for percussion or SFX) and sampler (Delta Modulation Channel) that used either PCM or Direct Memory Access.
With this knowledge I began the task of creating an NES sound-alike for the title track of Warfire. The first step was creating the appropriate synths with their designated waveforms (pulse, triangle and noise) and for this I used Vacuum synths from Pro-Tools.
A few of you may point out that the Vacuum is capable of blending two waveform shapes and my response is that only one Oscillator was used on each synth.
As with the NES, the triangle-wave was used primarily for bass lines and keeping true to the sound I used the triangle for my bass line.
The final synth was the noise channel and this made a pretty good snare sound. I have left the sample channel out of this composition so it may be used for SFX or a short voice sample.
I took the MIDI sequences from the piano version and assigned the main parts of interest to the pulse-wave synths and the bass line to the triangle synth with a snare drum-sound on the noise channel.
You’ll notice how the loop has the melody in the centre, this is so there is an ‘intro’ on the first pass and when it loops it feels like there is 16 bars of melody and 16 bars without. To get the NES sound I bounced it down as an 8-bit mono audio track.
In conclusion I’ve found it’s heaps of fun being retro and working to the same guidelines as our game music predecessors. Not only does the track sound like an NES soundtrack, it essentially IS one and this technique in my opinion is one that every composer needs in their arsenal for those times when the developers says ‘dude, can you make it sound like a NES?’.
Have a listen!