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I've noticed that many C64 games have a very distinct sound that I haven't heard on another console.

I cannot really describe it, but somehow, many melodies on the C64 sound metallic/futuristic/science fiction-like.

Does anybody how exactly this effect is called?

Also, is it possible to replicate it on the NES?

DRW wrote: I cannot really describe it, but somehow, many melodies on the C64 sound metallic/futuristic/science fiction-like.

Cannot you be any less precise ?

I belive you might be refering to the constant changing duty cycle of square waves ? With the NES it cannot be replicated as only 3 different duty cycles, however some games for other consoles such as Chrono Trigger (SNES) and Golden Sun (GBA) have replicated exactly that effect in software for some of their music.

Examples : Chrono Trigger Golden Sun

PS: This thread should probably be moved to the Music thread, even if it does not speak about NES music per se. I don't know really.

Bregalad wrote:Cannot you be any less precise ?

I thought that people know about that distinct C64 sound when someone names it.

Here are a few examples:
www.youtube.com/watch?v=Ne-09Bs_bRo
www.youtube.com/watch?v=ZeCA0Fvrg4s&t=30s
www.youtube.com/watch?v=ZeCA0Fvrg4s&t=3m30s
www.youtube.com/watch?v=bL35HvTIMmw
www.youtube.com/watch?v=UwBIDlcMU5Y

There are a number of things that kind of sound "C64" on the NES/famicom:

1. Constant arpeggios, especially with PAL 50Hz refresh rate.

2. Build snare drum sound out of alternating frames of square wave and noise. (i.e. a C64 channel can have tone or noise on a single channel, but not both at the same time; leads to very idiomatic kind of snare drum sound.)

3. VRC6 expansion can do an impression of C64 sliding duty cycle width. (Not quite as smooth.) It also has a saw wave.

Here's an example that I think does all of these at once: Cybernoid cover by Necrophageon (Check out instruments 06/07 for the drums especially.)

"Arpeggios" in this sense are the warbly chords in Pictionary, Silver Surfer, and Solstice for NES (which have Follin in common) and most Codemasters games for NES.

I'm guessing it's duty sweeps. The training/jogging cut scenes in Punch-Out!! for NES (which became the "Nigga Stole My Bike" meme) have a very primitive version of duty sweeps, but the NES pulse waves can't do more than 3 different duty cycles. So C64-style NES tunes such as the theme from Skate or Die 2 have to switch the duty cycle much faster.

[listens to fourth YouTube video, which is Double Dragon]
Yup, it's duty sweeps. If the level end bell in Number Munchers for Apple II has the same sort of "science fictiony" sound you're talking about, it's definitely duty sweeps.

I believe "that c64 sound" is just modulating the duty cycle every frame, and the VRC6 can approximate this.

The C64 can also do filter sweeps (and other fiilter effects), that double dragon is using them pretty prominently. There isn't really anything analogous to this in NES sound, though. At best maybe slowly adjusting the modulator strength on a VRC7 patch can to something a little bit similar, or maybe some clever DPCM sampels, but in general a PSG can't emulate a filter sweep.

As for the duty-sweeps, if you're not allowing Famicom expansion audio, I don't think the NES' 3 stages of duty even come close to sounding like it. I think the best you could do is maybe using 2 pulse waves playing the same thing but detuned. Smoothly varying the duty of a pulse shares a little bit of spectral similarity with two pulses at a slight detune. It's still obviously different than a smooth duty sweep, but I think it's a bit closer at least, though it unfortunately requires 2 channels.

Say what you want, but I prefer sound on the C64 over the NES. I just like how much more upbeat a lot of C64 music is.

I mean, dang: https://www.youtube.com/watch?v=93nIljXpqUY

I'd also think it looked better if it weren't for the poor resolution in 16 color mode (which somehow seems more colorful than the entire NES color palette.)

I'd like to see this be done on the NES:

I always thought it always sounded too buzzy. It does work for some songs though, so that's not to say I hate it, the C64 has some excellent songs. I just prefer the NES and Game Boy's sound to it.

Sogona wrote:I always thought it always sounded too buzzy.

I think the biggest problem with the SID is a lack of effective per-channel volume control. Basically everything has one loudness, which makes it difficult (but not impossible) to balance or do subtle orchestration. I suspect this lack of volume control is part of the reason why SID composers put so much expression into little notes and timbre effects (e.g. arpeggios and duty slides).

I guess that's the reason for a lot of Commodore 64 songs sounding more "excited" than NES songs.

rainwarrior wrote:I think the biggest problem with the SID is a lack of effective per-channel volume control. Basically everything has one loudness, which makes it difficult (but not impossible) to balance or do subtle orchestration. I suspect this lack of volume control is part of the reason why SID composers put so much expression into little notes and timbre effects (e.g. arpeggios and duty slides).

That's not to say there is no volume control. The S setting in the ADSR registers for each channel sets the sustained volume, as analogue synthesizers traditionally did.

If you have one channel with a S(ustain) of 15 and another channel at 8, they will NOT be the same loudness.

This sounds just like volume control per channel...

Espozo wrote:This sounds just like volume control per channel...

But it's not exactly. I haven't used the SID myself, but my understanding is that it's ADSR envelopes only. You can set the sustain level, but attack and decay are times, not levels. It's the time it takes to attack to and decay from maximum level. I wonder what it sounds like if you set it to the minimum, I don't know if you can change the sustain to effectively make your own software controlled envelope, my guess is there would be lots of clicks, unless only re-triggering the ADSR on note changes. Would be interesting to know.

Yes, there is a sustain part of the envelope which you can use for a partial volume control. You can also use the filter to attenuate one or two of the channels (while also filtering), or you can use the triangle wave on a channel to make it quieter (since it's not as loud as the other waveforms).

I also tried a trick where you cancel the attack early, going straight into release, allowing notes to have an attack that doesn't go all the way up, but this was a little bit problematic on hardware tests (the envelope doesn't seem to like being updated while it's running, some writes don't appear to go through).

So, yes, there are ways to do some forms of volume control on the SID, but every one of them is flawed. Of all the chips I've written music for that actually had any volume control at all, the SID has the worst. Almost everything else has a very straightforward way to attenuate individual notes (e.g. NES, AY, Pokey, any YM FM chip, etc...)