Sound level meter - Frequently Asked Questions

This section describes how to set the measurement mode, measured value (measured quantity), level range, frequency weighting characteristics, and dynamic characteristics.

<Memo>
For the meaning of the terms, please refer to the "What's New" → Ono Sokki Report section, "What is a Sound Level Meter?".

1. Setting the measurement mode

There are two measurement modes: instantaneous value (INST) display mode and maximum value per second (TactMax) display mode. You can switch between them each time you press the [Tact Max] panel switch. The selected measurement mode is displayed in the upper left corner of the screen as "INST" for the instantaneous value and "TMAX1" for the maximum value per second.

◆Operation

• Set the panel switch function to function 2.
  Press the panel switch [2nd] to enable function 2.
  
• Press the panel switch [Tact Max].
  Each time you press the [Tact Max] panel switch, it switches between instantaneous value (INST) and maximum value per second (TACTMAX).

2. Setting the measurement value (measured quantity)

The measurement value is switched using the panel switch [LP / Leq…]. Each time you press the panel switch [LP / Leq…], the measurement value will switch.

<Memo>
LX (Time-Factorized Noise Level) can be displayed after the LX calculation is complete. It cannot be displayed on the normal measurement screen.

3. Setting the Level Range

■ Level Range Value List

There are two level range setting modes: wide range and normal range, which is used in combination with a level recorder. For normal measurements, we recommend setting it to wide range, which minimizes the risk of over- or under-measurement. Please refer to the following table to set the appropriate range according to your application and purpose.

■ How to set the level range

The level range value is set by pressing the panel switch [LEVEL△・▽] so that the bar indicator is near the center. Each press of the panel switch [LEVEL△・▽] increases or decreases the value in 10dB increments.

■ Over/under level warning function

The over/under level warning function displays "OVER" when the input level is 10dB or more above the upper limit of the set level range, and "UNDER" when the input level falls below the lower limit of the set level range. If an over level warning (OVER) is displayed, the level range value will be increased, and if an under level warning (UNDER) is displayed, the level range value will be decreased. Note that the UNDER display will be shown at the lower limit - 5dB of the bar indicator when the normal range is set, and at the lower limit when the wide range is set.

4. Setting the frequency correction characteristics

There are three types of frequency weighting characteristics: A, C, and FLAT. The frequency weighting characteristic is set using the panel switch [A/C/FLAT] depending on the measurement purpose.

■ Measurement purpose and frequency correction characteristics

Please set the frequency weighting characteristics according to your measurement purpose, referring to the following table.

■ How to set frequency weighting characteristics

Each time you press the panel switch [A / C / FLAT], it switches in the following order: A-weighting → C-weighting → FLAT → A-weighting →…

5. Setting Dynamic Characteristics

There are four dynamic characteristics: FAST, SLOW, IMPULSE, and 10ms. The time constant is set using the panel switch [F/S/IMP] according to the purpose of measurement.

■ Measurement purpose and dynamic characteristics

Please set the dynamic characteristics according to your measurement purpose, referring to the following table.

■ How to set dynamic characteristics

Each time you press the panel switch [F / S / IMP], it cycles through the following modes: FAST → SLOW → IMPULSE → 10ms → FAST →…