This might be a bit of a philosophical question but does a AS3340 based VCO sound the same as a 555 based one? I would think that in the end a triangle is a triangle and so on - but does it work that way in practice? I dont think I’ve heard any side by side comparisons.
1 Like
It depends on the circuitry, I guess, but the 555 doesn’t have a triangle core; it’s a square wave oscillator that charges a capacitor with a constant voltage. If you tap the voltage off that capacitor, you get something that looks a bit like a triangle wave, but isn’t:
To get proper sawtooth or triangle waves, you need to charge/discharge the capacitor with a constant current (which is how the 3340 does things).
1 Like
I don’t know but if the question is to be resolved I had some ideas. In any side by side comparisons have it be rigorous and complete. After the oscillator have the signal chain through some typical filters and typical amplifiers. Record to an audio recorder of a amplifier or a mixer output and a video recorder of an oscilloscope. Check the variables on the oscillators to make sure they’re given the equivalent amount of voltage / amplitude and voltage / frequency and check the audible and oscilloscope visual tuning before. Give the voltages of the same voltage / frequency and give a comparison of octaves. Give the filter sweep a comparison. Hear the sound repetitively.
-Fumu / Esopus
No. In fact, CEM and AS chip clone sound different.
How different? Not much. However, pulses from different machines all have their own character.
Jupiter-8
JP 8000
Juno 60
MS-20
Nord Lead
Oberheim OB-6
Prophet-5
Prophet-6
Hell, just look at different models of game boy pulses:
Source: game boy sound comparison
You can listen to examples in the source.
Original DMG:
Original DMG with pro-sound mod:
DMG “Play it Loud!” edition:
Gameboy Pocket:
Gameboy Pocket with pro-sound mod:
Gameboy Light, with light on:
Gameboy Color:
Gameboy Color with pro-sound mod:
Gameboy Advance:
GBA SP with light on:
GBA SP with light off:
Gameboy DS:
4 Likes
I think the answer is, yes, a perfect triangle (or whatever) wave is a perfect triangle (or whatever) wave and will sound like any other perfect triangle (or whatever) wave.
But they’re generally not perfect.
5 Likes
Yep, this. Perfection is also just one timbre, and isnt strictly the best outcome either! 
2 Likes