• This is an optional test. To enable it click the checkmark at the bottom right and touch "In Progress". You can now open the test by clicking the arrow.
• This procedure is really only useful if you can move the sub, although as an experiment it might useful to know where a better sub location is as advice to the client.
• You'll see the signal generator we used before as the test. Get your notes on the true mode frequencies you determined earlier.
• This is where the marking the nulls on the floor can be handy.
• Tune the signal generator to the lowest width mode frequency and adjust the gain to a comfortable level. You should recreate the null pattern we discovered earlier.
• Slowly move the sub along the floor towards the null for this mode. As you approach the null you should detect the intensity of the tone decreasing in any peak area.
• The end result of cancelling the mode is to create a more even area of sound level between the seats. Try listening in the seats to see if this happened.
• In the HAA Workshops we experiment with ways to mitigate more than one mode with the sub(s) position.
• In a mostly rectangular room you should see that the changes we make to the yellow zones correlates to what's happening in the room.
• Once you've completed testing touch the leave arrow on the top left. Mark the item complete and add any notes about your testing.
• You can do the same with length modes or any mode which presents an issue. The strategy of using seat position for length modes and sub position for width modes is only a suggestion.