Always consult the Owners Manuals and FAQs first.
FM3 information is being added as it becomes available, but it's preliminary and not final until release

Realtime Analyzer block

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Available on which products

  • Axe-Fx III: 1 block
  • FM3: yes
  • Axe-Fx II: no
  • AX8: no
  • FX8: no

Channels or X/Y switching

  • Axe-Fx III and FM3: no

What is the RTA

The RTA provides detailed visual feedback of the audio spectrum. Possible uses are described below.

Many users will just use it because it looks pretty and dynamic.

It can point out frequencies where undesired feedback occurs. You can then use a PEQ to cut those frequencies.

“Use it to identify problem frequencies or as a spiffy screen saver.” source

It can used to test the hardware I/O. For example, to test the Instrument input: (source)

  1. Go to a blank preset
  2. Create a chain that connects Input 1 to the RTA block. On a separate row create a chain where the Synth block feeds Output 3
  3. Set the Synth Type = Sine, Tracking = Off, Frequency = 1000 Hz
  4. Connect an instrument cable from Output 3 (left or right) to the Instrument Input
  5. Set the Input 1 / Instrument A/D Input Level (Home->Setup->I/O) to 50%
  6. Turn the Out 3 Level knob all the way up
  7. The Input 1 yellow LED should be lit. Red should not be lit. Go to the RTA block Config tab. Set Bands to 128, Window to Blackman. Go to the RTA tab. There should be a narrow spike at 1 kHz (three bands). There should be no other bands showing power except maybe a little noise at the highest bands. The spike at 1 kHz should be about 2 1/4 divisions below full-scale

It can be used to measure the output of other equipment, in conjunction with the Synth block. For example, to measure the frequency response of an external EQ or distortion pedal, set the Synth block to Pink Noise, send the Synth's signal through the pedal and back again, and use the RTA to measure and see the response.

Position of the RTA on the grid

The RTA block requires an input signal and doesn't send a signal out, so its output doesn't need to be connected.

Watch the RTA

Scroll to the RTA block and press Edit to view the dynamic meters. It makes for a great display during performances.

To make the peaks remain longer visible, adjust Decay Time.

Turn the Value knob to select the desired band, and the frequency of the selected band will be displayed in the upper left corner.



Parameter Axe-Fx III / FM3
Decay Time yes
Input Select yes
Bands yes
Window Type yes