The Level Adjuster multiplies the value received on the Input one plug by the value received on the Input two plug. It can be used for an effect similar to ring modulation (This is not true ring modulation, which is balanced and suppresses the carrier), or to apply an low frequency modulation to a signal (amplitude modulation), or to scale a control voltage or audio signal by a fixed/variable amount.
The two inputs are multiplied together, then normalized.
(e.g. 5V * 2 V = 1V, (5 * 2 ) / 10)
NOTE: To apply an volume envelope to audio from an ADSR module you should use the VCA module, as it changes the volume of the signal using a decibel scale, not the linear scaling of the Level Adjuster.
Using the Level Adj module in place of a VCA will result in an un-natural sounding envelope, the VCA module also uses less CPU.
The Level Adj module is intended for controlling the output of LFO’s and other control voltage modules, not for audio gain control. It can also be used for Tremolo and amplitude modulation of audio where you would expect to have a linear response to the gain voltage.
Note: When selecting the Level Adj module from the modules panel it has default values set of 8V on both the Input 1 and Input 2 plugs. It’s a good move to set these to 0 volts when adding the module, as you can get some unexpected offset voltages when these plugs are connected to an IO module and shared with another container.
Plugs.
Left Hand Side:
Input 1:- (Voltage) First input signal A
Input 2:- (Voltage) Second input signal B
Note if a negative voltage is applied to Input 2 the Level Adj will function as a variable gain inverter.
Right Hand Side:
Output:- (Voltage) Normalized Output signal = (A × B) ÷ 10
Note: Normalization of the output means that if the voltages on Input 1 (A)= 5V and Input 2 (B) = 2V then 5*2 = 25 the output voltage will be 25 ÷ 10 = 2.5 not 25V
and likewise if A= 6V and B = 3V then 6*3 = 18 once again the output voltage will be 18 ÷ 10 = 1.8
Using a Level Adj module as an inverter.
Using the Level Adj module in this way we can provide both +ve and -ve ADSR envelopes, and still have the overall level controlled in the usual way.
A delayed LFO using ADSR and a Level Adj module.
A delayed LFO is one that instead of being on permanently gradually fades in as a note is played. The Level Adj is ideal here as we would want a linear gain control for the LFO output. The ADSR is just wired up to provide a variable attack for the “fade in”, the overall level is used to provide the maximum level, Sustain is set at 10, and a fixed release of 4 is set so that the LFO output fades away rather than stopping abruptly after the key is released.
Converting Linear voltage “curves” to Exponential voltage curves.
By feeding the same input voltage to both input 1 and Input 2 of the Level adjuster we are effectively creating an exponential output. The first Level Adj module has Input 2 set to 10 volts so that the structure retains the original 0 to 10 V input scaling. You can see the effect of the module on the output of an ADSR 2 using an ED Plotter module (the bottom display is the Linear output from the ADSR).
The fixed values can be altered to scale both the input and output ranges.
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