MA 1 - Output Signal Level Adaptation Troubleshooting

During the course of the MA 1 calibration procedure, there is a process that measures the output level feed from the audio interface outputs into the KH monitors (Output Level Adaption process).  A level that is too low or a difference between the channels does not necessarily have anything to do with a different signal coming from the interface. Problems with the cabling or incorrect layout settings for the input connection can also lead to different level differences.

Pre Requisites

1. In any case, all speakers must be in “Network Mode” when using MA1. The corresponding switch is located on the backplate of each speakers.
   Note: In network mode, all switches and potentiometers are bypassed, as MA1 now take over full control of the data stored on the internal DSP. The only exception is the "ground lift switch".
2. A common root cause is an incorrect “Input Connection” (yellow box) of the monitors when
   creating the initial layout. Depending on the Neumann monitors type up to 3 different input signals are supported
   • Analog
   • AES3 or S/PDIF
   • AES67 (only in the AES67 version)

3. Select the correct Input Connection. For example, if the monitors are connected to the audio
   interface via analog XLR, select Input “Analog”

   

   If you use the digital output on the interface to connect it to the KH monitors, select “S/PDIF” in
   MA1 in the input selection for the corresponding monitors or AES3 on the KH750DSP subwoofer.

   Note: “Automatic” is also an option, as this selection automatically choose the analog inputs.
   However, if a digital connection is also patched in parallel, you should explicitly select the
   desired connection.

4. In MA 1 on the Audio interface setup page that precedes the Output Level window , confirm the Starting output channels are the correct output pair connected to your monitors:

   

   Some interfaces may include a software mixer - examples include RME's Totalmix, Focusrite Control, Universal Audio Console, and MOTU's Cuemix.

   With these, ensure signal is getting routed to the appropriate output pair selected in MA 1.  During the Output Level Signal Adaptation test, you should see metering in its UI.

   Note: If using an Neumann MT 48 Audio Interface, ensure DAW1 is enabled in Menu > Settings > USB IO.

5. Lastly, try slowly increasing the output or monitor level on your interface and retrying the Output Signal Level Adaptation process again.

There are various indications of level differences that point to different causes.

If you receive an error message stating a difference in levels, start here:

A level difference between ~1dB- - ~3dB is an indicator, that there is no signal on the subwoofer input. Reason could be, no or a faulty connection between audiointerface output and subwoofer input.

Note: In some cases, a monitor controller between audio interface and subwoofer could be also the rootcause of an issue, for example when there are different speaker outputs at the controller and the audio signal is not routed to the expected output.

A level difference in the range of 40dB is an indicator, that one channel at the subwoofer input is missing. Please check if both L/R cables are connected.

A level difference between ~4dB- - ~5dB is an indicator that the connection from the subwoofer output to the satellites/monitors is not correct. Reason could be a faulty cable or the XLR connector is not plugged in correctly.

A level difference in the range of 80dB is an indicator, that only one satellite/monitor is connected right. Please check if both satellites/monitors and cables are correct.

Note: During the level adaption test the speakers are on mute. At this time the Neumann LED Logo on the speaker front is “light rose”. Because of this you will hear nothing. This is normal.
If your audiointerface has an additional headphone out, you can hear the test signal (sinus) which is muted on the speakerts in different levels. (-10/-20/-30/0dB)

Depending on the measurement scenario, there may also be a message that the volume is too low. This message can also be generated if the speakers are not connected correctly or, for example, an intermediate monitor controller is muted or the signal is routed incorrectly or defective cable/connection.

If the signal is actually really too low, as in this example (17,1dB), when the cabling is correct and the layout is set up correctly, the message would look like this. In this case, you should turn up the master bus on the audio interface or existing monitor controller accordingly.

Conclusion:

In addition to the correct cabling for the audio signals (shown in orange), a network connection of the monitors to a network switch is also required for MA1 to work (shown in green). The computer with the MA1 software should also be connected to this network switch and be in the same IP subnet as the monitors.