I felt like doing another detuned sawtooth patch, so I did one I've reproduced on other synths, the riff in Futurecop's "1988 Girls." It's a nice brassy, full sound when voiced well.

Just a simple two-part sawtooth layer, with part 1 pitching up and part 2 detuned. I goofed when I first made this and exited the program without saving; fortunately it was fast to make, and even faster to remake.

By sheer chance, the demo recording resembles the theme from the Flight of the Navigator.

It sounds a bit FM, but it's actually some heavy, modulated waveshaping on a triangle oscillator, plus some LP filter. No layers needed this time!

A bandpassed pulse form with some resonance and waveshaping to give the attack more body.

Sine wave, pitched down, plus an enveloped waveshaping for more punch.

It's not quite as low-fi as the NES, but it sounds approximately similar.

This is actually a pretty complicated one. I wanted to make something vocal sounding, and it's modulating pitch, cutoff, and resonance on a band-passed sawtooth. Resonance on this filter tends to come out sounding harsh and grainy so I took some time finding ways to keep the settings in a musical range, eventually settling on a "synth meow" timbre.

I upgraded the synth to use 2x oversampling on the state-variable filter this evening. This means that before the filter runs, the incoming samples from the oscillator are upsampled(for every 1 incoming sample, two are generated). We generate the new samples by convolving the Blackman-Harris window over the old ones. The SVF is run over this double-rate buffer, and the output is subsequently decimated back down to the original rate. The resulting filter is more accurate and smoother-sounding.

The patch I made after doing this modulates cutoff, resonance, and amplitude over a sawtooth - it's perhaps not the most challenging example, but the timbre is very reliant on filter quality, and it hits my soft spot for long, evolving pad sounds.

This is haaard to synthesize well. I "finished" it, started typing up this post, and then went back and spent another 20 minutes on it. The final thing is two layers of noise, filtered in different ways, both of them using the "fast sawtooth LFO" trick that makes it sound more like multiple impulses. A third layer might make it sound richer, but I stopped there. For a really good example of this style of synth clap see "Being Boiled" on Human League's Travelogue.

At first I thought I would try making a cymbal. This is even harder than making a hand clap, so after an hour or so I stopped and started noodling and ended up with this instead. Triangle wave used for the "tine" attack, 25% pulse for the sustain.

These are pretty easy to make - two sawtooths and some pitch and filter modulation - and a lot of fun to play.

Over the past few days I've been improving oscillator and filter quality. Yesterday I improved the pulse waves by doing the correct form of additive synthesis on the rectangular function(instead of taking a square wave and awkwardly rescaling it). After I did that I looked into improving the tonal noise, which has always had inherent aliasing, being an oscillator based on a small single-cycle noise pattern. I decided, based on my success with oversampling elsewhere, to oversample the tiny initial waveform 4x, making aliasing much less present until you hit C-6 or so. In the process I discovered that I had made the wrong constants for the Blackman-Harris window that I'm using to oversample things, so the filter is a little cleaner now too. I also shrank the tonoise waveform to 32 samples instead of 64. The downside of doing this is that it's more "tone" and less "noise," the upside is that it performs better and it's more straightforward to modulate.

Today I made just about the simplest patch you can make with the tonoise oscillator: envelope the noise in and out. This gives you an approximation of Karplus-Strong style pluck sounds, only more metallic sounding.

It's just carefully shaped noise.

Sawtooth, downpitched, resonant low-pass envelope. Waveshaped for added punch. Demo is the Good Times riff roughly as interpolated in Rapper's Delight. I took some time and used a click track to actually get the rhythm almost acceptable but not really(ha, foiled by latency again).

I spent a while on it, but I think it's kind of awful. Waveshaped square wave plus sine wave plus miscellaneous other stuff(filter, pitch etc.)

It's the "Jump!" sound, and it's accurate enough to start phasing against the original recording. I didn't play the actual riff, the keyboard doesn't have the range to do the correct voicing to begin with, but I do play some notes around the appropriate octaves and chords. For examples of the sound: http://www.synthtopia.com/content/2009/06/30/van-halen-jump-demo-oberheim-obx-a/

This is an original patch which actually uses the highpass filter(unlike almost every other sound I've done which uses LP or BP). The goal was to make something that gets the smooth character of gradually enveloped sines, but with a definite high end buzz, which is provided by a sawtooth as usual. Playable, but not quite what I had hoped for.

I aimed for something like a DX7 sound by waveshaping one part against a sine and filtering it to get the "tine," and then leaving the other part a simple sine. It's playable, however it sounds nothing like the famous "DX7 Rhodes", it's harsher and it aliases more readily.

I was feeling low about this synth yesterday, but today I come back with this sound which invokes a bit of that "Atari 8-bit" feel by using the tonal noise oscillator where it really shines - gritty bass sounds. I layer it with a sawtooth to distinguish the high end and fill it out.

Two tonal noise voices at vastly different pitches with LFO.

Another tonal noise pad, layered with a square. Very "horror ambience."

I improved the patch editor so that I could hold the shift key for fine tune adjustments. This helped me set the pitch LFO on this patch to 12.001 semitones(it still wasn't quite fine enough I guess). It's a sine wave but I waveshape the attack so that it's more squarish-beeper like and then filters out to make a cleaner echo.

Yes, it's another detuned sawtooth patch. This one went for a mix of filtered and not.

It's a detuned sawtooth patch, but it's also a pulse width modulation patch. At first I thought I would have to add an inverted sawtooth oscillator or negative gain to pull off this classic trick, but then I realized that I could do the inversion with the waveshaper. I felt very clever when I did that, and then I added some modulation to the waveshape at attack time so that you get a blast of sawtooth followed by the PWM timbre.

I didn't include a delay in the ADSR controls, so it's harder to do vector-synth style pads, but not totally impossible. Here I sweep through three different oscillators.