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I'm beginning to suspect it's a matter of how we put it rather than much of an actual disagreement . I agree that whatever the cost of a wavetable, a triangle must have been an obvious choice over a sine for reasons that you already mentioned. Though, if they'd wanted a reasonable sine, I think they would have gone for something more complex than sixteen step 4 bit wavetable. Say, 6 or 7 bit output, double the period increment rate, and a 32 step half-sine LUT fed by the output of the existing triangle circuitry.

I didn't know about the length counter LUT. Seems like the designers went crazy over some very specific use cases.

I am saying "sparing any ROM" because one of the peculiarities of a lookup table design is that you need a table to look samples up in. This would most likely be implemented as ROM on the chip surface, and definitely using a type of memory. Do you disagree? Either way, you would still need phase counters, so yes, there is complexity added by a LUT design. Also, sixteen samples at 4 bit resolution is distorted to the point where the difference to a triangle wave hardly matters. That's still only half the triangle time resolution.

But I agree somewhat with your point. For some extra chip area they could have done a LUT design. With some extra bit depth and some good table size they might even have made it reasonably resemble a sine wave. But why would they? Sines aren't as musically versatile unless you have a lot of them or some complex modulation techniques.

That's a pretty cool thing! I couldn't read it at gunpoint, though.

The SID is a different design for sure, but I have no doubts that the basic idea of waveform generation by simple logic applied to the phase accumulator output is similar to that of the NES.

Anyway, "doable" is far from the only concern when designing consumer electronics. Production/design cost and time probably weighed more in both the case of the SID and the 2A03 APU.

Rainwarrior, the thing with using pulses/saws/triangles over sine waves is that you don't need lookup tables. By feeding a ramping phase accumulator (this is a simple counter that has the frequency register value added to it every some division of the cpu clock) directly into some simple logic circuitry, you can generate those three basic waveforms without sparing any ROM (the triangle as Shiru explained). There is a nice writeup on how exactly this was done on the SID in this interview of its designer: http://sid.kubarth.com/articles/intervi … annes.html.

You don't need to work for long periods of time on a single song to improve your skills. Much like any puzzle analogy you may come up with, working on multiple problems at once will sometimes be the most productive way to attack them.

What made you think that would go away with time? Why do people care about using the same language at all?

To stay on topic, I love dance music. I can dance to a lot of shitty music I'd rather not listen to normally, just for the sake of dancing.

I like digital, but I can appreciate the ritual of taking a disc out and putting it on the platter, or rewinding tapes or whatever.

I dunno, have you heard Disasterpeace?