Điều Chế Tần Số 4

Sound create use FM synthesis and use 16 bit for high quality. Create sound use C program. Sample have different frequency (power 2) and length. Last several sample have wave frequency above Nyquest limit 48000 Hz/2 = 24000 Hz

Some effect sound like effect in game Strider Hiryu (ストライダー飛竜) from Capcom 1989 (robot gorilla in level Siberia) and Sonic Hedgehog 1 from Sega 1990 (sonic jump in large ring at level end if have more than 100 ring).

Algorithm:
• One carrier and modulate pair
• Modulate frequency 1.4 of note (carrier frequency)
• Modulate amplitude (β) change from 0.0 to 10.0 across note
• Hill envelope with top at 0.1 of note length