The preferences can be accessed from the application menu or by clicking the "Preferences" button on the master player.
Audio Devices
The audio devices table lists the channels of the audio output devices connected on your computer. You need to relaunch DynamDJ if you connect new devices or disconnect existing ones in order for these changes to take effect. You can check the channels that shall be used by DynamDJ. Click the test button on a channel to play a sound on the corresponding speaker. Channel volumes should be set in a way that no speaker produces a louder test sound than another. You may need to use the Audio MIDI Setup (/Applications/Utilities/Audio MIDI Setup) tool included in Mac OS X for further audio devices configuration.
If more than 2 channels are enabled, room placement can be used. For this, distribute the speakers connected to the channels physically in the room. By clicking the "Specify Speaker Locations" button, a window will pop up in which you can inform DynamDJ about the speakers' physical locations. More precisely, you will be presented a graphical representation of the room viewed from above, in which you can position dots of different colors, as they appear in the audio devices table, each of them representing a speaker.
If the "Remember audio devices volumes" if checked, channel volumes will be set to the ones defined here each time you launch DynamDJ.
Player Volume Field for Room Placement
The volume field is the scalar field visualized in the picture. It can be thought of as the virtual sound field around a player. The player's sound output can thus, in theory, be heard louder at locations where the sound field is brighter. When room placement is used, the volume of each player on the different speakers depends on the value (= brightness) of this player's sound field at the relative position of the speaker in it. Moving a player towards a speaker will make the player's audio louder on this speaker.
Since each player may produce stereo sound, it actually has two sound fields, one on its left side and one on its right side. The slider right under the picture can be used to set which field should be visualized most. This is only a matter of this visualization, the slider's setting has no effect outside the preferences window.
The spread slider can be used to adjust how much the two channels should blend together on the areas not strictly left-side or right-side the player. The strength is the field's overall amplitude, the height can be decreased to limit the field more towards the horizontal axis, the size defines how much the field should stretch out in the room.
If "Visualize Volume Fields" is disabled, the fields will not be visualized in the main window's room placement component; this may increase performance.