6 - Sample Edit

Compressor

	O The Start and End points	Compressor
		The Digital Compressor is a digital (non-realtime) equivalent of an analog
	are “remembered” from module	dynamic range compressor with attack and release times, adjustable
	to module so that you can	threshold, adjustable ratio, and three modes of operation.
	perform successive operations
	on the same section of the	v To Compress a Sample:
	sample.

1.Press the Sample Edit key. The LED illuminates and the main sample edit screen appears.

2.Select the sample that you want to compress using the Data Entry Control, INC/DEC keys, or the numeric keypad.

3.Press the Tools 3 function key (F4). Another row of function keys appears.

If the sample is stereo, a 4. Press the Comprsr function key (F2). The following screen appears.

pop up dialog box will ask you	A waveform display appears with several controls.
to select left, right or both sides.
		Waveform Display
	Editing
	Fields

Vertical	Zoom	Zoom In	Zoom In
Scale	Out	at Start	at End
Magnifier		Point	Point

OHolding down the Enter • Editing Fields: Move the cursor to the desired field to change the

	key while turning the Data Entry	Start and End points of the sample section to be compressed.
	Control allows “fine tuning” of	• Magnification: Adjusts the vertical scale for 1x, 2x, 4x, or 8x
	the value by one number per
		magnification. Pressing the button repeatedly rotates through the
	click.
		4 options.
	• The Zoom controls also	• Zoom Start: Magnifies the waveform to display finer detail around
	change the editing resolution.
		the Start point of the selected section.
		• Zoom End: Magnifies the waveform to display finer detail around
		the End point of the selected section.
		• Zoom Out: Reverses the effect of Zoom Start & Zoom End.
		5. Specify the Start and End points for the section of the sample to be
		processed.
		6. Press OK when you have selected the desired section or press Cancel to
		cancel the operation.

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6 - Sample Edit

Compressor

7. If you pressed OK, the following screen appears.

Mode

•RMS: Root-mean-square or an “average of the magnitude of the signal”. RMS represents the “true” energy content of a signal.

•Peak: Uses the peak amplitude of a signal to determine the amplitude. The peak amplitude is a meaningful measurement in a digital system because of the 96 db (16-bit) headroom limit.

Threshold

•Above: Only signal levels above the threshold % will be affected by the compressor.

•Center: Signal levels above as well as below the threshold % will be affected by the compressor.

•Below: Only signal levels below the threshold % will be affected by the compressor.

•%: Determines the threshold level as a percentage of 100% of 16-bits.

Compression Ratio

Determines the amount of compression or expansion. Ratios of greater than 1:1 compress dynamic range. Ratios of less than 1:1 expand dynamic range.

•Compression: Reduces the amount of dynamic range. Levels remain more constant.

•Expansion: Expands the amount of dynamic range. Changes in level are exaggerated.

Attack Time

Determines how quickly the gain will be turned down. The attack time is variable from 1 to 999 milliseconds.

Release Time

Determines how quickly the gain will be turned up. The release time is variable from 1 to 999 milliseconds.

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6 - Sample Edit

Compressor

8.Press OK when you have set the desired options or press Cancel to cancel the operation.

			Compressor Threshold
Only signal levels ABOVE			100%						1:1
									2:1
the Threshold percentage
will be affected by the			50%						10:1
compressor.	Threshold
			0%
								Above
Signal levels ABOVE as			100%						1:1
well as BELOW the									2:1
Threshold percentage will	Threshold		50%						10:1
be affected by the
compressor.

0%

Center

Only signal levels BELOW	100%
the Threshold percentage	Threshold
will be affected by the	50%					10:1
compressor.
						2:1
						1:1
	0%

Below

EOS 4.0 Software Manual 223