A reference level on analog inputs is the sensitivity of the input.
For devices with lower output volume you need to raise the sensitivity.
When connecting Studio devices with hotter studio levels you need to make the inputs more insensitive to have enough headroom not to overload the inputs.
With analog outputs it is similar, but here it is not the sensitivity of the input it is the signal strength/volume on line level.
When connecting external devices like FX, you need to look to get the right reference level not to overload the inputs on the other side with a too hot signal.
In this case it is not a FX it is an active monitor.
Here you need to choose most likely the reference level with the lowest output volume so that it does not become too loud.
So why you choose +13 or +19 on the outputs towards your monitors?
It will most likely become way too loud, choose the lowest instead.
The benefit is
a) that you do not need to turn the output fader too low, which reduces dynamic/SNR
b) it is not so loud
Ideal is, when you get at fader position around 0dB the volume that you want to use as your maximum volume.
So ... use the
- reference level with the lowest volume on your analog output of your recording interface
(ref level selection in TM FX behind the wrench symbol)
- lowest sensitivity on the analog inputs of your active monitors, some have volume knobs for it
If 0 dB on the output fader is still much too loud, then you should solve the "level mismatch" as I told you by
- using a switchable attenuator (see forum link, posting from MC) or
- an analog monitor controller / volume knob or
- by using one of RMEs reference converters with a nice volume control where the last volume setting is being remembered and where switching between active monitors and headphones or when plugging/unplugging is being performed with a volume ramp-up, slow enough to turn the volume down if it appears to be too loud.
The point is, that it is relatively easy to accidentally get 0 dB setting on the TM FX output fader, e.g. when
- selecting another snapshot
- selecting another workspace
- switching to speaker B
- double-clicking the output fader
- by a key combination
So you need so solve the level mismatch proactively as described above so that 0 dB do not "hurt" (ears, equipment).
BR Ramses - UFX III, 12Mic, XTC, M-1620 Pro D, RayDAT, ADI-2 Pro FS R BE, X10SRi-F, E5-1680v4, Win10