Trim Controls Volume Controls Master Volume

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T8S This information is applicable to the T8S ToneMatch® mixer
T4S This information is applicable to the T4S ToneMatch® mixer
T1 This information is applicable to the T1 ToneMatch® audio engine

Introduction

On the ToneMatch mixers (and many others) there are three controls that affect the volume

  • Trim
  • Channel Volume
  • Master Volume

Questions:

  • What do these controls do?
  • When do you use the different controls?
  • Should they all be the same?

Background

Mixers accept inputs from various sources. Here are some examples:

Input Source Signal Strength Output Voltage
Instrument
Piezo pickup (no preamp)
Very Low 50–100 mV
Microphone -30 dBu
1.5 to 70 mv
Instrument


Acoustic Guitar with pickup
Electric Guitar

100 mV rms to over 1 V rms[1]
Instrument Level


Electronic Keyboard

-20dBv
Line Level
Consumer
-10dBv
Line Level
output from preamps
Tip-Ring-Sleeve
0dBu 0.78 V
Line Level
Professional
Tip-Ring-Sleeve
+4dBu 1.25 V

Gain Staging

Your first adjustment for any input to your ToneMatch mixer is the Trim setting. The exact position of the Trim will vary depending on signal strength of your input source. The correct setting for any particular source may be different from your other sources.

T1® Trim Pots

Set Up Your Source

Set your source at the maximum that it will be when performing.

  • Microphone
Sing directly into the microphone using close microphone technique (lips just brushing the windscreen). Sing as loudly as you will sing during your performance. You want to set the Trim to work at your maximum volume.
  • Instrument
Turn your input as high as it is likely to go during performance.

Set Input Trim

Turn the Trim setting up until the Trim Light is solid green with occasional flickers of yellow. Use the Trim lights as your guide. (The exact position of the Trim knob is not important).

TrimlightsOK.gif

If you see flickers of red (below), turn the Trim down. You are definitely nearing or in compression. Turn the Trim down until there are no red flickers.

TrimlightsNo.gif