We've just updated MediaWiki and its underlying software. If anything doesn't look or work quite right, please mention it to us. --RanAS
S-DSP/Noise: Difference between revisions
From SnesLab
(linkify Nyquist) |
(only one timbre) |
||
| Line 1: | Line 1: | ||
Noise clock table | Noise clock table | ||
Hardware noise on the SNES is generated by a 15-bit Fibonacci [https://www.eetimes.com/tutorial-linear-feedback-shift-registers-lfsrs-part-1/ linear feedback shift register]. [1] Note that the noise sampling frequency is the perceived pitch (due to overtones) even though it is double ([https://www.techtarget.com/whatis/definition/Nyquist-Theorem Nyquist]) that of the fundamental. The [[S-DSP/Gaussian Filter|Gaussian interpolator]] does not operate on the hardware noise generator. | Hardware noise on the SNES is generated by a 15-bit Fibonacci [https://www.eetimes.com/tutorial-linear-feedback-shift-registers-lfsrs-part-1/ linear feedback shift register]. [1] Unlike the NES which has two hardware noise timbres, the SNES only has one. | ||
Note that the noise sampling frequency is the perceived pitch (due to overtones) even though it is double ([https://www.techtarget.com/whatis/definition/Nyquist-Theorem Nyquist]) that of the fundamental. The [[S-DSP/Gaussian Filter|Gaussian interpolator]] does not operate on the hardware noise generator. | |||
{| class="wikitable" | {| class="wikitable" | ||
Revision as of 22:46, 21 June 2023
Noise clock table
Hardware noise on the SNES is generated by a 15-bit Fibonacci linear feedback shift register. [1] Unlike the NES which has two hardware noise timbres, the SNES only has one.
Note that the noise sampling frequency is the perceived pitch (due to overtones) even though it is double (Nyquist) that of the fundamental. The Gaussian interpolator does not operate on the hardware noise generator.
| Value | Sampling Frequency | Pitch | Example |
|---|---|---|---|
| 00 | 0 Hz | off | |
| 01 | 16 Hz | C0 - 38¢ | |
| 02 | 21 Hz | E0 + 33¢ | |
| 03 | 25 Hz | G0 + 35¢ | |
| 04 | 31 Hz | B0 + 7¢ | |
| 05 | 42 Hz | E1 + 33¢ | |
| 06 | 50 Hz | G1 + 35¢ | |
| 07 | 63 Hz | B1 + 35¢ | |
| 08 | 83 Hz | E2 + 12¢ | |
| 09 | 100 Hz | G2 + 35¢ | |
| 0A | 125 Hz | B2 + 21¢ | |
| 0B | 167 Hz | E3 + 23¢ | |
| 0C | 200 Hz | G3 + 35¢ | |
| 0D | 250 Hz | B3 + 21¢ | |
| 0E | 333 Hz | E4 + 18¢ | |
| 0F | 400 Hz | G4 + 35¢ | |
| 10 | 500 Hz | B4 + 21¢ | |
| 11 | 667 Hz | E5 + 20¢ | |
| 12 | 800 Hz | G5 + 35¢ | |
| 13 | 1.0 kHz | B5 + 21¢ | |
| 14 | 1.3 kHz | E6 - 24¢ | |
| 15 | 1.6 kHz | G6 + 35¢ | |
| 16 | 2.0 kHz | B6 + 21¢ | |
| 17 | 2.7 kHz | E7 + 41¢ | |
| 18 | 3.2 kHz | G7 + 35¢ | |
| 19 | 4.0 kHz | B7 + 21¢ | |
| 1A | 5.3 kHz | E8 + 9¢ | |
| 1B | 6.4 kHz | G8 + 35¢ | |
| 1C | 8.0 kHz | B8 + 21¢ | |
| 1D | 10.7 kHz | E9 + 25¢ | |
| 1E | 16 kHz | B9 + 21¢ | |
| 1F | 32 kHz | B10 + 21¢ |