Sound level meter - Frequently Asked Questions
Question number FAQ-1177
Setting the level range
■ Setting the level range
Level range
The level range can be set in 10dB steps from 20dB to 80dB to 60dB to 130dB, with six different settings available.
Level Range Value Setting List
Refer to the following table to switch to the appropriate range value, which includes the level range you wish to measure. (The table uses the notation from the IEC standard.)
| Level rangefrequency correction characteristics | Commonupper limit of measurement | Lower limit of measurement | ||
|---|---|---|---|---|
| A characteristic | C characteristics | FLAT | ||
| 60～130dB | 140／137dB | 55（55） | 55（55） | 55（55） |
| 50～120dB | 130 | 45（45） | 45（45） | 45（45） |
| 40～110dB | 120 | 35（35） | 35（35） | 36（35） |
| 30～100dB | 110 | 26（25） | 31（30） | 36（35） |
| 20～90dB | 100 | 26（25） | 31（30） | 36（35） |
| 20～80dB | 90 | 26（25） | 31（30） | 36（35） |
*・・・LA-1240／1250 ： 140dB
LA-1350／4350 ： 137dB
( ) ... LA4350 only
【Note】
Values below the lower limit of measurement in each level range are affected by the noise inherent in the sound level meter itself. When taking measurements, set the level range value so that the measured sound falls within the range between the upper and lower limits of measurement.
Switching the level range
The level range is switched using the panel switch [LEVEL (▲・▼)] so that the instantaneous value is near the center of the bar indicator. Each press of the panel switch [LEVEL (▲・▼)] increases or decreases the level range in 10dB increments.
Over/under level warning display function
The over/under level warning function displays an "OVER" warning if the level is 10 dB or more above the upper limit of the level range display, and an "UNDER" warning if the level is 5 dB or more below the lower limit of the level range display.
If an over- or under-level warning is displayed, switch the level range using the panel switch [LEVEL (▲・▼)].
【Note】
The LA-1240/1250/1350/4350 already checks for excessive signal levels at the signal stage, before the signal reaches the displayed level.
Therefore, depending on the sound frequency and waveform, the OVER mark may be displayed even if the displayed level is not more than 10dB above the upper limit of the level range. However, this is not a malfunction. In such cases, please switch the level range to prevent the over-level warning from being displayed.
Last updated: 2002-01-09