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View topic - How many octaves does the Sega Master System reach, sound wise?

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  • Joined: 26 Jun 2006
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How many octaves does the Sega Master System reach, sound wise?
Post Posted: Tue Mar 26, 2002 7:55 pm
OK, first of all, I know that the NES is capable of producing tones ranging from approximately A-1 to B-8. The triangle waveform is one octave lower. Now when I tried out both the NES and SMS sound test ROMs, I noticed that the SMS's lowest pitch is one octave higher. How many octaves can the SMS produce? What tones does it range from and to approximately?
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finaldave
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Post Posted: Wed Mar 27, 2002 9:42 am
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> OK, first of all, I know that the NES is capable of producing tones ranging from approximately A-1 to B-8. The triangle waveform is one octave lower. Now when I tried out both the NES and SMS sound test ROMs, I noticed that the SMS's lowest pitch is one octave higher. How many octaves can the SMS produce? What tones does it range from and to approximately?

Can't most PSGs produce pretty much any frequency anyway? I mean we were saying on the other board that some frequencies can't be heard by the human ear.
So, range == a lot, much more than A-1 to B-8!
I would imagine this goes for the NES too, but I don't know for sure...

FM based stuff does seem to be passed an octave number and a keycode, but PSG chip are more flexible in terms of pitch. Whether the notes sound any good and are in tune is another matter entirely!
 
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SMS range
Post Posted: Thu Mar 28, 2002 7:29 am
PSG tone channels: minimum = 109 Hz, maximum = 18643Hz (approximately).
Using PSG periodic noise mode: minimum = 6.8Hz, maximum = 1165Hz

I can't convert these to octave thingies (A#6 and all that) right now, because I can't find the nice Java convertor I found before. VGMTool's write to text function includes such conversion, though, so you can find the value of any note in a VGM.

Maxim
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finaldave
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Re: SMS range
Post Posted: Thu Mar 28, 2002 8:28 am
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> PSG tone channels: minimum = 109 Hz, maximum = 18643Hz (approximately).

Is that because the mixer cuts it off at 18643Hz? i.e. in theory the PSG can be programmed with period=1 but the analogue circuits won't handle that?

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> Using PSG periodic noise mode: minimum = 6.8Hz, maximum = 1165Hz

> I can't convert these to octave thingies (A#6 and all that) right now, because I can't find the nice Java convertor I found before. VGMTool's write to text function includes such conversion, though, so you can find the value of any note in a VGM.

> Maxim
 
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Re: SMS range
Post Posted: Fri Mar 29, 2002 8:15 am
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> > PSG tone channels: minimum = 109 Hz, maximum = 18643Hz (approximately).

> Is that because the mixer cuts it off at 18643Hz? i.e. in theory the PSG can be programmed with period=1 but the analogue circuits won't handle that?

I was actually misremembering the value at which the analogue circuits faile to handle it. Listening to this again, it cuts off at PSG value 0x08 which corresponds to 13982Hz. The oscillators keep going up to 0x02 or 0x01, because the noise channel keeps outputting when tuned to that value (0x01 is a bit unsure).

Maxim
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This is really confusing me here.....
Post Posted: Fri Apr 12, 2002 7:29 pm
First of all, the SMS can do about 7 octaves. However, from every single SMS specs. documents that I read, they said each of the tone channels have FOUR octaves. Does it REALLY have JUST FOUR octaves instead of seven? Or is that bulls***? Or is there a reason why there are 4 octaves? Or are there really 7?
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Which docs?
Post Posted: Sat Apr 13, 2002 9:45 pm
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> First of all, the SMS can do about 7 octaves. However, from every single SMS specs. documents that I read, they said each of the tone channels have FOUR octaves. Does it REALLY have JUST FOUR octaves instead of seven? Or is that bulls***? Or is there a reason why there are 4 octaves? Or are there really 7?

If you mean the lists on a million websites, they all copied it from each other and it's crap. The tech docs are (quite) accurate.

frequency = 3579545/32/n

where n=0 to 1023. Periodic noise gives 1/16 frequency. (And is used a lot in Lemmings, which I'm ripping now. Cool.)

Maxim
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