# Output Tab Window

> > 1. Device Icon & ID Button - see the description above.
> > 2. Analog Output Meter - This meter displays the level of the analog output before D/A conversion, in the range -48 to 0 dBFS.
> > 3. Speaker Out Selection - This menu selects the software output that is sent to the speaker outputs.
> > 4. Speaker Out Level - This knob controls the speaker output level.
> > 5. Headphone Out Selection - This menu selects the software output that is sent to the headpone outputs.
> > 6. Headphone Level - This knob controls the output level of the front panel HP 1 output.
> > 7. Dim - Engage dim if you want to lower the output level by 15 dB. This function is convenient when you want to briefly lower the playback volume in the speakers or headphones in order to hold a conversation without completely muting the output.
> > Duet's top panel touch buttons may be set to engage Dim on the Speaker outputs, the headphone outputs or both at the same time. See Device Settings Tab Window.
> > 8. Sum to Mono - Engage this to sum the left and right channels of the output to mono. At many points of the production process, this function is useful to check mono compatibility. For example, when recording with a stereo pair of mics, it's always a good idea to sum both channels to mono and check for unevenness in the frequency range caused by phase cancellation and reinforcement of particular frequencies. If the sound changes significantly or sounds "hollow" when summed to mono, this may indicate phase issues caused by a less than optimal mic placement.
> > When mixing, it's also a good idea to check mono compatibility. Beyond questions of phase, any masking caused by overlapping frequencies is most easily heard when listening in mono. Try starting a mix with Sum to Mono engaged - once you have something that sounds good, then disengage Sum to Mono and revel at the beautiful stereo mix you've created!
> > Duet's top panel touch buttons may be set to engage Sum to Mono on the Speaker outputs, the headphone outputs or both at the same time. See Device Settings Tab Window.
> > 9. Mute - Engage this to mute the output.