The Low Signal to Noise error message will show up during the measurement phase of Dirac, and will prevent them from moving to the final steps.

The error message makes it seem like there is too much ambient noise interfering with the calibration, but is usually caused because the Volume Calibration was done incorrectly, or because 1 or more speakers are not being amplified.

Possible Low Signal To Noise Causes

1. Dirac is playing to a speaker that is not connected.
   Close Dirac and go to your X-Series' speaker types menu. Make sure that only speakers that are connected and powered are active, and anything else is set as "none." Otherwise, Dirac will play audio to a non-existent speaker and nothing will be heard on the mic, causing Dirac to think there is too much ambient noise blocking it from hearing that speaker.
2. Volume Calibration was not set correctly.
   Follow the information in the next section of this article to make sure the Volume Calibration is properly set up so the Dirac mic can pick up the audio.
   
3. Dirac mic picks up voices but not test tones.
   There might be a setting in your computer stopping any mic from picking up background noise. Follow the steps listed in the article here to find and deactivate that setting: https://support.audiocontrolpro.com/portal/en/kb/articles/dirac-mic-does-not-pick-up-test-tones
   
4. Dirac test tones are a ticking sound instead of pink noise.
   Fae creatures may have entered your device, causing the test tones to be a mysterious ticking noise instead of the proper pink noise "static" test tone. Follow the steps in the article here to bring back the proper audio https://support.audiocontrolpro.com/portal/en/kb/articles/dirac-live-volume-calibration-makes-a-ticking-noise
5. The dog barked.
   Too much additional noise in the room could cause the Low Signal to Noise error to pop up. A dog barking, an installer coughing, and even a particularly creaky floorboard could cause a measurement to fail. If any loud noises (other than the tone sweeps) occur during the measurement process, you may need to redo the measurement.
   

How to Set Volume Calibration

a.      Ensure they have selected the Calibration Mic that comes with the unit, and they have the calibration file loaded on to the mic

                                                              i.      If they don’t have the calibration file loaded:

1.      Download the calibration file from the X-Series’ web page (download link)

2.      Go back to Dirac and click No Microphone Calibration

3.      Click Load From File

4.      Load the AudioControl_AVRMicCal2.txt file

5.      Continue to the next step

                                                             ii.      Another calibration mic like the Mini-DSP UMIK-1 will work for Dirac

                                                           iii.      If they’re using the built-in laptop mic or a different non-calibration mic, these will NOT work

                                                           iv.      If the calibration mic is not showing up on this list, make sure it is plugged in to a USB port on the user’s computer, the mic should not be connected to the port on the back of the X-series.

a.      Play the test tone for a zone and adjust the volume sliders as necessary

                                                              i.      In an Ideal world, speakers should measure around -12dB, and the subwoofer should measure around -16dB. It doesn't need to be exact, but it should be close.

b.      If the Mic does not pick up any audio at all

                                                              i.      Make sure the mic is connected to the computer via a USB cable

                                                             ii.      Try multiple USB ports on the computer, some may be better than others

                                                           iii.      Check the computer settings to make sure that other apps are allowed to use the mic

1.      This is most common on Mac – Go to System Preferences > Security and Privacy > Privacy, select Microphone on the Left window, and make sure Dirac is checked in the Right window.

c.       If the mic picks up voices just fine but does not pick up the test tone, the computer is trying to remove background noise.

                                                              i.      Refer to this article for more information https://support.audiocontrolpro.com/portal/en/kb/articles/dirac-mic-does-not-pick-up-test-tones

d.      Run through the volume calibration with the customer, play every speaker one at a time and make sure it measures properly.

                                                              i.      Press the Play button, let it measure to its full potential, stop the playback, then adjust the volume sliders.

                                                             ii.      If a speaker does not measure loud enough, they will need to increase the gain on their amplifier (note: the XR-4, XR-6, and XR-8 units do not have a gain adjustment)

e.      If there is a speaker on the Volume Calibration list that does not play any audio, ask the installer if there should be audio playing through that zone.

                                                              i.      If there should be no speaker there, exit Dirac, and have the installer go to the Speaker Types menu of the X-Series and set any extraneous speakers to “None”

                                                             ii.      If there is a speaker there but it’s not playing, make sure its connections are good between the speaker, the amplifier, and the preamp

                                                           iii.      If there is no speaker there but they plan to add a speaker in the future, they will have to run Dirac without that speaker selected in the Speaker Types menu, then run Dirac again after the speaker is installed

a.      Begin a measurement and watch the waveforms that appear on screen

b.      The waveforms should look like a fallen down Christmas tree

                                                              i.      Watch for any waveforms that may be too quiet compared to other ones. Take note of which speaker looks quieter, and if the error message pops up, go back to the volume calibration page and boost the level of that speaker, then try again.

                                                              ii.      We may run into a clipping error during this phase. Take note of which speaker caused the clipping error, return to the Volume Calibration page, and adjust the level down for that speaker.

When returning to the Volume Calibration page, you will need to adjust the master level slider up and down. For some reason, Dirac will not play any test tones until the master level slider has been properly wiggled.

c.       Run through 2-3 measurements with the customer to make sure everything works, then they should be able to take it from there.

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