Engine speed determines how fast EVERYTHING is played. Including sound, glitches, graphics, and memory write.
(pwn't)
When the engine speed is lower, EVERYTHING is slower. That is correct, so PAL releases will play everything 6/5 as quickly as NTSC releases to compensate the frame rate loss. If you suddenly switch to PAL emulation while running an NTSC ROM, everything does play slower as you said, but it does not mean that PAL releases are slower than NTSC releases.
The time it takes per cycle in NTSC is 1/60 of a second because 60 Hz = 1/60 of a second. The time it takes per cycle in PAL is 1/50 of a second because 50 Hz = 1/50 of a second.
This makes PAL physically slower than NTSC. However, when this occurs, the music's notes are transposed down one whole step. So, if some composers want to actually force their music to play at the desired notes instead of the transposed notes, they'd compose their music & transpose it up one whole step.
When this is done, the audio's frequency is increased, proving that engine speed loss can be compensated.
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Technology: the one thing that's hated & cursed at by all engineers, technologists, scientists & technicians!
Basically, the main clock source for the microprocessor was the TV's frequency itself. As with all CPUs, any clock source of a certain frequency range can be used (& by the looks of it, the 6502 CPU inside both the 2A03 & 2A07 chips can use clocks within the same frequency range). The only difference is the internal circuitry for each chip.
The 2A0X chips have something called a frequency divider (which is a condensed circuit that accepts an input frequency & spits out an output signal of a different frequency). such circuits have to be built to handle a particular input frequency so that it can produce the proper output signals for the rest of the peripherals. In the 2A03, the circuit is built to handle 60 Hz, whereas the 2A07's circuit is built to handle 50 Hz.
I'm sorry I couldn't be of much help.
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Technology: the one thing that's hated & cursed at by all engineers, technologists, scientists & technicians!
Vrc7 is an expansion chip on which you can make the the most realistic sounds. Sometimes, though, the multi-peice instruments I make are better than Vrc7 in terms of how realistic it gets.
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