Alto Professional ACOM2 User Manual
Page 3
3
FRONT PANEL CONTROLS
Couple Switch
1. Dual mono – When activated, this links two mono channels together.
2. Ch 1 master -
When the Couple Switch is engaged, Channel 1 will take control of
both channels and override all the controls and switches of Channel 2 with the
exception of the SC Monitor, SC External, SC Filter, Bypass and Peak Limiter control.
Expander/Gate
3. Threshold control - Adjusts the threshold level for the Expander/Gate
section.
4. Ratio control - Determines the expansion ratio when the signal drops
below the threshold level.
5. Threshold LED - The "+" LED lights up when the audio signal goes below
the set Threshold. The "-" LED lights up when being used as an expander.
Compressor
6. Threshold control - Adjusts the threshold level for the Compressor section in the range of -40 dBu to
+20 dBu. Signals that go above the set threshold will be compressed.
7. Threshold LED - Shows the state of the input signal in relation to the threshold level. If the input signal
falls below the set threshold level the left "-" LED will light up and the signal will not be compressed. If the
input signal rises above the set threshold level, this signal will be compressed and the SKC (Smart Knee
Control) level will be shown by the middle "0" LED.
8. Ratio control - The ratio between the input and output level of audio signals exceeding the set threshold.
9. Attack control - Determines how fast the compressor reacts to audio signals that exceed the set
threshold.
10. Release control - Determines how fast the compressor returns to unity gain when the audio signal falls
below the threshold level.
11. Auto switch - Allows the attack and release controls to be automatically set based on the audio signal.
12. Output gain control - Adjusts the output signal by a maximum of 20 dB to recover the level lost during
compression.
13. SC External switch - Separates the connection between the audio input and the sidechain path but
allows an external signal through the sidechain return jack.
14. SC Monitor Switch - Connects the sidechain control signal to the audio output, muting the audio input
and monitoring the sidechain signal being returned via external signal processors.
15. SC Filter switch - Activates a low-cut filter in the sidechain path, eliminating unwanted noise generated
by low frequencies.
16. Smart switch - Hard knee mode will be converted into SKC (Smart Knee Control) mode for musically
transparent compression.
17. Bypass switch - Turns off the corresponding channel to make an A/B comparison of the processed and
unprocessed signal.
18. Input/output meter switch - Switches to the input level meter when turned on; switches to the output
level meter when turned off.
19. Input/output level meter - Displays the input or output level.
20. Gain reduction meter - Displays the amount of gain reduction.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28 29
25
26
27
28 29
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28 29
25
26
27
28 29
1
2
3
4
5
6
7
8
9
10
10
11
11
12
12
13
13
14
14
15
15
16
16
17
17
18
18
19
19
20
20
21
22
23
24
25
26
27
28 29
25
26
27
28 29