Additional Features:
- Frequency Range: Selective: 18 Hz to 22 kHz (1/3 octave); 14 Hz to 28 kHz (1/1 octave); Linear: Typical 3 Hz to 75 kHz (1-dB)
- Band-Pass Filters: 31 active 6-pole Butterworth third-octave filters and 31 overlapping 1/1 octave filters at 1/3 octave, intervals covering 11 octaves
- In accordance with standard: IEC R 225-1966, DIN 45652, DIN 45651 and ANSI S1.11-1966, Class II & III Requirements; and unweighted linear response
- Centre Frequencies: 20 Hz to 20 kHz
- Attenuation outside Pass Band: > 75 dB at 5 f o and 1/5 f o (1/3 octave); >60 dB at 8 f ο and 1/8 f o (1/3 octave)
- Filter Shift: Manual or Automatic with Level Recorder, 1/3 octave or 1/1 octave steps for 1/1 octave analysis
- Remote Control: Automatic to/from Level Recorders Types 2317 and 2309 via cable AO 0034
- Input Impedance: 10 k Ω in series with 15 µF
- Input Terminating Impedance: ≤ 100Ω
- Input Voltage: Maximum 2 V sinus (2.8 V peak)
- Output Impedance: < 5Ω in series with 2.2 µF
- Output Terminating Impedance: >/= 10 k Ω/1 nF
- Magnetic Sensitivity (50 Hz): Approximately 1 mV output for 100 A/m field strength
- Operating Temperature: -10 to + 50°C (+14 to +122° F)
- Storage Temperature: -20 to +50° C (-4 to +122° F) Batteries removed
- Influence of Temperature on Attenuation: <0.5dB (-10 to +50B °C)
- Influence of Humidity on Attenuation: < 0.5 dB for 0 to 90% relative humidity at ≤40° C without condensation
The Bruel & Kjaer 1625 portable Octave Filter Set is primarily intended for use with Sound Level Meter Type 2230, 2231 or 2233. The 1625 permits third-octave frequency analysis, and octave frequency analysis with a step of octave or third-octave. Fully automatic recording of the analysis is possible with a Level Recorder Type 2317, 2306 or Type 2309. The scanning of the filter and the Level Recorder are fully controlled by the Filter Set to obtain an optimal recording. Two scanning speeds are available for analysis of levels measured with "Slow" or "Fast" time weighting.
The selectable centre frequency range is from 20Hz to 20kHz and a linear position gives a frequency band from 3Hz to 75kHz. The analyzed signal may also be weighted by selecting "A" or "C" frequency weightings on the Sound Level Meter.
The level in each frequency band can be read on the Sound Level Meter's digital display, the centre frequency of the filter being displayed on the Filter Set. The filter centre frequency being selected manually by push button.
The filter scanning is electronically programmed and controlled to obtain an RMS read out error less than 0.5 dB over the whole analysis range. The settling time and the paper drive speed are controlled by the Filter Set to ensure a precise recording in a minimum time.
The filter scanning is electronically controlled and programmed to optimize the recording. The Filter Set increases the Level Recorder paper speed as the analysis band centre frequency is increased. Thus, an accurate recording is obtained in a minimum of time.
| Manufacturer | Bruel & Kjaer |
|---|---|
| Condition | Used |