Eng:Play Note () for () Beats (block)

Translate: - English - 中文 

Play Note () for () Beats
Category	Sound
Type	Stack

The Play Note () for () Beats block is a Sound block and a Stack block. The block will play the specified note with a set MIDI instrument for the specified amount of beats.

Prior to Scratch 1.2, this block used to be called Play Note () for () Secs, but was changed because the length of a beat can now be changed with the Set Tempo to () bpm block.

Example Uses

As the block plays a note, it is widely used when a song is played with the Sound blocks.

Some common uses for the Play Note () for () Beats block:

• Easy sound effects (numbers above 88 still work); very high and low notes make interesting sounds

repeat until <(x) = [0]>
play note (x) for (0.1) beats
change [x v] by (-1)
end

• Musical projects where you control instruments

forever
play note ((mouse y) mod (129)) for (0.1) beats

• Creating a song made by blocks

repeat (2)
play note (62 v) for (0.5) beats
End
repeat (2)
play note (69 v) for (0.5) beats
End
repeat (2)
play note (81 v) for (0.5) beats
End
play note (69 v) for (0.5) beats

Notation

The Play Note () for () Beats can sometimes be tricky to get used to since the notes and rhythms are notated with numbers, unlike sheet music. These diagrams may help:

Notes

The note names are written on the keys. Notes written in the two most common clefs (Treble clef and Bass clef) are connected to the piano. All notes can be written in an infinite number of ways. The most common enharmonic notes are included. A line going from a long red box means the notes go to the same key on the piano. Even though the drop-down keyboard shows only two octaves of notes (48 to 72), a number can be put in manually to get any note. To change octaves, simply add or subtract 12.

There are 128 notes on the MIDI keyboard, numbered from 0 (C_-1, about 8.18 Hz) to 127 (G₉, 12500 Hz). Each note is 1 higher than the previous, and the ratio of frequency is always ¹²√2 (approximately 1.06), with A₄ being 440 Hz.

Clef	Note	MIDI number	Frequency
Bass	C3	48	131 Hz
	C♯3/D♭3	49	139 Hz
	D3	50	147 Hz
	D♯3/E♭3	51	156 Hz
	E3	52	165 Hz
	F3	53	175 Hz
	F♯3/G♭3	54	185 Hz
	G3	55	196 Hz
	G♯3/A♭3	56	208 Hz
	A3	57	220 Hz
	A♯3/B♭3	58	233 Hz
	B3	59	247 Hz
Base and Treble	C4 (middle C)	60	262 Hz
Treble	C♯4/D♭4	61	277 Hz
	D4	62	294 Hz
	D♯4/E♭4	63	311 Hz
	E4	64	330 Hz
	F4	65	349 Hz
	F♯4/G♭4	66	370 Hz
	G4	67	392 Hz
	G♯4/A♭4	68	415 Hz
	A4	69	440 Hz
	A♯4/B♭4	70	466 Hz
	B4	71	494 Hz
	C5	72	523 Hz

Beats

This table shows the beat number values for the most common rhythms in the most common time signatures, interpreted in the most basic way.

	4	3	2	1.5	1	0.67	0.75	0.5	0.33	0.375	0.25
	8	6	4	3	2	1.33	1.5	1	0.67	0.75	0.5
	2	1.5	1	0.75	0.5	0.33	0.375	0.25	0.167	0.1875	0.125

See Also

• Play Drum () for () Beats
• Rest for () Beats
• Set Instrument to ()
• Music Projects