ACMT - Applied Computer Music Technologies Ltd

ACM510 Product Operating Guide
 
Access to plug-in parameters is provided by a fully resizable graphical user interface. Your host application may also provide access to parameter adjustments and additional configuration. Graphical User Interface
 
The plug-in settings are adjusted by clicking and dragging on the rotary controls or buttons. Some controls may have detents – these manifest themselves as areas in the rotation where the reluctance to move is increased such that you have to drag them a bit harder. They are intended to behave similarly to real controls which may have a 'click stop' at 0dB for example.
 
You can also adjust the controls by placing the mouse pointer over them and using the scroll wheel. In this case the detent has no effect.
 
Control Modes
 
The control mode determines the way in which the rotary controls respond to mouse movement. This can normally be configured via the host application preferences. Please refer to your host application documentation for details.

• Circular. In this mode, clicking on a control will move it immediately to the mouse pointer’s angular position. To adjust the control, drag the mouse pointer in a circle or an arc.
• Relative Circular (Default). This is the default mode unless changed by host application settings. Similar to circular mode, however moving the mouse will adjust the control relative to its current setting.
• Linear. In this mode, the control responds to vertical mouse movement. Drag up to increase the value, turning the control clockwise, or down to decrease the value, turning the control anticlockwise.

In all modes, double clicking the centre of a control will return it to its default position.
 

Control Functions
 
1. Input Gain
 
The input gain control selects the amount of gain applied to the signal before it enters the compressor. It has a detent at 0dB. A little more mouse effort is required to turn the control around the detent, a little like a 'click stop' on a conventional analogue control. This is designed to help quickly locate the 0dB point again if necessary.
 
2. High-Pass Filter
 
The HPF switch places a 75Hz high-pass filter into the side-chain. This helps to stop low frequency content from causing the compressor to pump or over compress.
 
3. Threshold
 
The threshold control sets the level at which the compressor begins to act. For example, if the threshold is set to -20dB, signals below -20dBu in level will pass through unaffected. Signal levels greater than the threshold will be progressively attenuated dependent upon the ratio control setting.
 
4. Attack
 
The attack control sets the speed with which the compressor reacts to signals greater than the threshold. The shorter the time, the quicker the compressor will respond to changes in input level and reduce the output. Use faster settings (anticlockwise) to aggressively control loud signals, or slower settings to allow the initial transient through before the compressor begins to act.
 
5. Gain Reduction Meter
 
The gain reduction meter shows the amount of attenuation applied to the signal as it passes through the compressor. The amount of attenuation depends upon the signal level, in conjunction with the threshold and ratio settings. Large amounts of gain reduction indicate that the compressor is having to act more strongly to control the signal level.
 
6.Release
 
The release control sets the speed with which the compressor recovers after the signal level returns to normal. A short time (anticlockwise) means the compressor will recover quickly, but this can also lead to an audible 'pumping' of the signal at high compression ratio settings. This is normal for a signal processor of this type, and in some cases is perceived as a desirable effect. If necessary, this can be reduced by slightly increasing the attack or release time.
 
7. Ratio
 
The ratio control sets the amount of compression applied to signals larger than the threshold. In simple terms, the compression ratio is the ratio of change in input level to change in output level.
 
For example, if the compression ratio is set to 10:1, a change of 10dB in input level (assuming it is already above the threshold) will only result in a 1dB change in output level. A ratio of 1:1 is equivalent to no compression, and in this case a change in input of 10dB would result in a change in output of 10dB also.
 
The ACM510 has a 'soft-knee' characteristic, providing a gradual onset of compression as the signal level crosses the threshold. This is similar to many older analogue designs, and generally thought to give a more natural sound.
 
8. Output Level
 
The output gain control, sometimes referred to as 'make-up gain', provides additional gain after the compressor, in order to make up for attenuation by the compressor. For example, if the threshold is set to -20dB, and the ratio to a high value, the aggressive compression will give good control of the signal but it will struggle to get much above -20dB and so may appear subjectively quieter.
 
By adding some extra output gain, the signal is brought back to its original average level – only this time the louder peaks will have been reduced. Switch the compressor in and out while adjusting this control in order to match the processed and unprocessed signal levels.
 
9. Effect In / Out
 
This is the plug-in bypass switch. With the switch on, the plug-in will be in the signal path. With the switch off, signals pass through unaffected.

ACM510 Technical Specification:
 
1. System Requirements (64bit Linux)

• Linux x86-64/AMD64 64bit e.g. Ubuntu 20.04 LTS or newer.
• A Linux VST or VST3 compatible host application.

2. Product Specifications

• Linux VST and VST3 compatible.
• Mono or stereo operation.
• Interpolated controls for smooth parameter changes with no 'zipper' noise.
• -18dBFS reference level for 0dBu.
• Input gain: -6dB to +12dB.
• Attack time: 0.1ms to 10ms.
• Release time: 100ms to 1sec.
• Threshold: +10dBu to -20dBu.
• Compression ratio: 1:1 to 10:1.
• Output make-up gain: -6dB to +20dB.
• Switchable side-chain high-pass filter (6dB / octave at 75Hz).
• Polarity invert switch.
• Output level trim (+/-6dB).

Please note: In the interest of continual product improvement, specifications may be subject to change without notice.

ACM510 Download Free Demo
 
1. System Requirements (64bit Linux)

• Linux x86-64/AMD64 64bit e.g. Ubuntu 20.04 LTS or newer.
• A Linux VST or VST3 compatible host application.

2. Free Demo Limitations

• Every 60 seconds the plug-in will fade to silence momentarily. To remove this limitation you will need to have purchased a product activation code.
• To remove the demo limitations, open the plug-in in your host application and click the lock button at the top left of the plug-in GUI to open the license entry dialogue. Type (or paste) your product activation code into the text box. You will then need to restart your host application to complete the process.

3. Product Support

• All downloads include their own installer, manual, and installation instructions. Easy to install with just a few clicks.
• If you need help downloading or installing the software please use our contact form to let us know.