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Sound and Vibration Instrument Hire and Calibration

B&K 2250 BZ 7222 Sound Analysis Specifications

To see the specifications for the various options available, click a link

Bruel & Kjaer Sound Level Meter
BZ 7222 : Sound Analysis Software
BZ 7223 : Frequency Analysis Software
BZ 7224 : Logging Software
BZ 7225 : Enhanced Logging Option
BZ 7226 : Sound Recording Software
BZ 7227 : Reverberation Time Option
BZ 7228 : Sound Insulation Option
BZ 7230 : FFT Analysis Option
BZ 7231 : Tone Assessment Option
B&K 2250 : Home Page
B&K 2250 : Specifications
B&K 2250 : Detailed Image
Bruel & Kjaer 2250 : Sound Level Meter Option - BZ 7222 included

Conforms with the National and International Standards:


Transducers are described in a transducer database with information on Serial Number, Nominal Sensitivity, Polarisation Voltage, Free field Type, CCLD required, Capacitance and additional information. The analogue hardware is setup automatically in accordance with the selected transducer


For microphones of known types, BZ 7222 is able to correct the frequency response to compensate for free or diffuse sound fields


Parallel Detectors on every measurement:
A or B-weighted (switchable) broadband detector channel with three exponential time weightings (Fast, Slow, Impulse), one linear averaging detector and one peak detector
C or Z-weighted (switchable) as above for A and B weighted
Overload Detector: Monitors the overload outputs of all the frequency weighted channels


X = frequency weightings A or B
Y = frequency weightings C or Z
V = frequency weightings A, B, C or Z U = time weightings F or S N= number between 0.1 and 99.9
For Storage
Full statistics

For Display and Storage

Start Time Stop Time Overload %
Elapsed Time LXeq LYeq
LAE LCeq - LAeq LVpeak
LASmax LAFmax LXImax
LYSmax LYFmax LYImax
LXSmin LXFmin LXImin
LYSmin LYFmin LYImin
LXIeq LYIeq LAIeq - LAeq
LAFTeq LAFTeq - LAeq Time Remaining

Only for Display as Numbers or Quasi-analogue Bars

LXN7 or LXUN7    

Measuring Ranges

Dynamic Range: From typical noise floor to max. level for a 1 kHz pure tone signal, A-weighted: 16.6 to 140 dB
Primary Indicator Range: in accordance with IEC 60651, A-weighted 23.5 dB to 123 dB
Linearity Range: In accordance with IEC 60804, A-weighted, 1kHz: 21.4 dB to 140 dB
Linear Operating Range: In accordance with IEC 61672, A-weighted 1 kHz: 24.8 dB to 140 dB
Peak C Range: In accordance with IEC 61672, 29.5 dB to 143 dB

Sampling For Statistics

The Statistics can be based on either LXF, LXS or LXeq:
Statistics LXFN1-7 or LXSN1-7 are based on sampling LXF or LXS every 10 ms into 0.2 dB wide classes over 130 dB
Statistics LXN1-7 are based on sampling LXeq every second into 0.2 dB wide classes over 130 dB
Full distribution saved with measurement

Measurement Displays

SLM: Measurement data displayed as numbers of various sizes and one quasi-analogue bar
Measurement data are displayed as dB values, housekeeping data as numbers in relevant format
Instantaneous measurement LXF is displayed as a quasi-analogue bar

Measurement Control

Manual: Manually controlled single measurement
Automatic: pre-set measurement time from 1 s to 24 hours in 1 s steps
Manual Controls: Reset, Start, Pause, Back-erase, Continue and Store the measurement manually


The last 5 s of data can be erased without resetting the measurement

Measurement Status

On Screen: Information such as overload and running/paused are displayed on screen as icons
Traffic Lights: Red, yellow and green LEDs show measurement status and instantaneous overload as follows:
Yellow LED flash every 5 s = stopped, ready to measure
Green LED flashing slowly = awaiting calibration signal
Green LED on constantly = measuring
Yellow LED flashing slowly = paused, measurement not stored
Red LED flashing quickly = intermittent overload, calibration failed


Initial calibration is stored for comparison with later calibrations
Acoustic: Using Sound Level Calibrator Type 4231 or custom calibrator. The calibration process automatically detects the calibration level when Sound Level Calibrator Type 4231 is used
Electrical: Uses internally generated electrical signal combined with a typed-in value of microphone sensitivity
Calibration History: up to 100 of the last calibrations made are listed, the last 20 calibrations can be viewed on the instrument

Signal Monitoring

The input signal can be monitored using an earphone/headphones connected to the headphone socket, or it can be fed to the output socket
Output Signal: Input conditioned; A, B, C or Z-weighted.
Gain Adjustment: -60 dB to 60 dB
LXF output (every ms) as a DC voltage between 0 V and 4 V
DC output for calibration purposes: 0 dB ~ 0 V and 200 dB ~ 4 V.
Headphone Signal: Input signal can be monitored using this socket with headphones/earphones. Gain Adjustment: -60 dB to 60 dB

Voice Annotations

Voice annotations can be attached to measurements so that verbal comments can be stored together with the measurement
Playback: Playback of voice annotations can be listened to using an earphone/headphones connected to the headphone socket. Gain Adjustment: -60 dB to 60 dB

Text Annotations

Text annotations can be attached to measurements so that written comments can be stored with the measurement

Data Management

Project Template: Defines the display and measurement setups
Project: Measurement data stored with the Project Template
Job: Projects are organised in Jobs Explorer facilities for easy management of data (copy, cut, paste, delete, rename, view data, open project, create job, set default project name)


Multi-user concept with login. Users can have their own settings with jobs and projects totally independent of other users


Date, Time and Number formats can be specified per user
E&OE - specifications subject to change without notice.
* Our standard hire charges are based on a 4-day minimum period, details other options.

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