| Output Sound-Pressure Levels | 74, 84, 94, 104, or 114 dB re 20µPa |
| Nominal Output Frequencies | 125, 250, 500, 1000, 2000 or 4000 Hz |
| Actual Output Frequencies | Preferred per ANSI S1.6-1960 and ISO R266: 125.9, 251.2, 501.2, 1000, 1995 or 3981 Hz ±3% |
| Reference Conditions | Temperature: 20°C (68°F)
Atmospheric Pressure: 1013 mbar† (760 mm of Hg)(30 in. of Hg)
Relative Humidity: 65%
Microphone Effective Volume: 0.5 cm3 (0.03 in.3)(nominal for GenRad 1961 Electret-Condenser Microphone*). |
| Accuracy of Sound-Pressure Level | Under stated reference environmental conditions, at 114-dB SPL and at all frequencies except 4000 Hz: ±0.25 dB for cavity alone or when used with any adaptor (except 1 1/8-in adaptor: ±0.5 dB at 1000 Hz only); at 114-dB SPL and 4000 Hz; ±0.5 dB. At output levels other than 114-dB SPL, tolerance is increased by ±0.1 dB |
| Temperature Coefficient of Sound-Pressure Level | Less than ±0.02 dB/°C (±0.01 dB/°F) for all frequencies except 4000 Hz |
| Tone Burst Signals | test signals provided as prescribed by ANSI S1.4-1971; IEC Sound-Level Meter Standard 651. In tone-burst modes, output can be either continuous (Set Fast/Slowor Set Crest Factor) or a series of bursts (Fast, Slow or Crest Factor), as selected. Level is uncalibrated and continuously adjustable. In Fast or Slow, peak amplitude of tone-burst is identical to that of continuous signal. In Crest Factor, rms value of tone-burst sequence is identical to that of continuous signal. Fast: Repeated tone bursts at 1000 Hz, 200-ms duration every 2s, for measuring sound-level-meter Fastrise response; amplitude is continuously variable from 72 dB to 118 dB re 20µPa; background level is 20 dB below burst level. Slow: Repeated tone bursts at 1000 Hz, 500-ms duration every 10s, for measuring sound-level meter Slow rise response; amplitude is continuously variable from 72 to 118 dB re 20µPa; background level is 20 dB below burst level. Crest Factor: repeated tone bursts at 2000 Hz, 5.5 ms duration, 40-Hz repetition rate, crest factor X3, for measuring rms detector-indicator accuracy and amplifier crest-factor capacity; rms amplitude is continuously variable from 75 to 11 dB re 20µPa. |
| Variable Sound-Pressure-Level Control | Enabled only in tone-burst modes. Provides 11 dB of adjustment |
| Electrical Output | Output provided from nominal 600Ω shortable source. Voltage proportional to sound pressure; 230-mV rms nominal output corresponding to 114-dB SPL. |
| Distortion | Less than 1% THD acoustical or electrical |
| Battery Test | Internal circuitry checks condition of battery continuously. Automatic instrument shutdown when battery voltage falls below acceptable range. |
| Microphone Coupling | Transducer cavity accommodates following 1-in. microphones: GR1961 electret condenser*, GR 1971 ceramic, Western Electric 640AA and Tokyo Riko MR103 |
| Environment | Temperature: -10 to +50°C (+14 to +122°F), operating, -40 to +70°C (-40 to +140°F), storage with battery removed.
Humidity: 0 to 90% RH, operating. |
| Accessories Supplied | Coupler-adaptor to accommodate GR 1962 ½-in electret-condenser microphone* and GR 1983 Sound-Level Meter microphone; 3 spare desiccant kits; battery; instruction manual |
| Accessories Available | Adaptor set that includes coupler-adaptor for 3/8-in GR1954 Noise Dosimeter microphone; coupler-adaptors and "0" ring for 1-in, ½-in, and ¼-in B&K microphones, and coupler-adaptor for 1 1/8-in Shure Brother microphones. carrying case. |
| Power | Powered by 9V alkaline battery, Mallory MN 1604 or Eveready 522 recommended. Battery provides at least 8 hours continuous operation. |
| Mechanical | Dimensions (WxHxD): Approximately 280 x 67 165 mm ( 11 x 2 5/8 x 6½ in.)
Weight: Approximately 1 kg (2.2 lb) |