Analyze Your Measurements - JBL Room Mode Correction User Manual

Analyze Your Measurements

Most of your measurements for LSR6328P systems will fall within one of the six examples
which follow. Here are detailed descriptions of each example:
Example A:
Absence of a floor interference dip indicates the loudspeaker was probably mounted
against a wall in a well-damped room, and not too far away from the monitoring position.
You may proceed to equalize the LF room mode for flat response.
One Low Frequency Peak
0dB
-1 dB
-2dB
-3dB
-4dB
-5dB
-6dB
-7dB
-8dB
-9dB
-10dB
-11dB
-12dB
-14dB
-16dB
20Hz
Example B:
There are no room mode effects here, but there is a dip due to floor or possibly wall
reflections. If the dip is no greater than about 4 or 5 dB, you can ignore it - and let this
response remain as is. If the dip is greater than about 6 dB, you might try moving your lis-
tening position forward just a bit. This may alleviate the dip somewhat. Otherwise, no
equalization is required
One Dip
0dB
-1 dB
-2dB
-3dB
-4dB
-5dB
-6dB
-7dB
-8dB
-9dB
-10dB
-11dB
-12dB
-14dB
-16dB
Example C:
This is a very common pattern you will see in fairly live small to moderate size spaces.
The dip may result from both floor and wall reflections and as such may be fairly wide. Try
moving the monitor and/or your listening position to minimize the dip's width before pro-
ceeding. Equalize the peak.
One Peak and Dip Exceeding 6 dB
0dB
-1 dB
-2dB
-3dB
-4dB
-5dB
-6dB
-7dB
-8dB
-9dB
-10dB
-11dB
-12dB
-14dB
-16dB
10
22 24 25 26 28 31 35
20Hz 22 24 25 26 28 31 35
20Hz 22 24 25 26 28 31 35
45 47 57 62 68
41 50 53 76
45 47 57 62 68
41 50 53 76
41 45 47 50 53 57 62 68 76
85 90 95 105 115 126
85 90 95 105 115 126
85 90 95 105 115 126