Quest Model 2700 Impulse Sound Level Meter
The Quest 1700 (Type 1) and 2700 (Type 2) Impulse Sound Level Meters are the base models within our Advanced Series of meters.
These meters are designed to provide you with a measurement of Sound Pressure Level (SPL) and maximum SPL for a variety of combinations of user-selected response time constants, frequency weightings, measurement ranges, and optional octave band filter settings.
1700 / 2700 Technical Specifications
Model 1700 : Type 1
Model 2700 : Type 2 ANSI S1.4-1983, IEC 651-1979.
3-1/2 Digit Liquid Crystal Display with an additional Quasi-Analog 60 dB indicator in 2 dB increments. The level display indicates to 0.1 dB resolution. Indicators are included for Battery Check, Hold, and Overload Indication.
Modes of Operation:
Measures Sound Pressure Level (SPL) and Maximum Level (MAX). Peak Level (PEAK) and Impulse Level (IMP) can also be measured.
Model 1700 Meter only; With Model BK4936 Microphone -- 27 dBA.
Model 2700 Meter only - 35dBA. Using Linear Weighting with an Octave Filter Set. The minimum measurement varies depending on the filter frequency selected.
With Model BK4936 or QE7052 Microphone -- 120 dB with 20 dB Crest Factor. (140 dB if measuring a sinusoidal signal.) Overload indication will occur if the upper range is exceeded. Optional microphones for model 1700 will shift the measurement range upward.
Frequency Weighting Networks:
A, B, C, and Linear. When using a filter set, any one of the weightings may be selected.
Slow, Fast, Impulse, and Peak. (The Peak onset time constant is less than 50 microseconds). Peak measurements may be made in either A, B, C, or Linear Weighting.
Removable precision 1/2 inch pre-polarized condenser (electret) microphone is standard. Optional 1/2 inch, one inch, and other microphones are available for the model 1700 only.
Directly accepts 0.52'' microphone, other sizes with proper adapter. The removable preamp will drive up to 100 feet of cable with negligible signal loss.
Model 1700: Preamplifier model 056-856. The input impedance
is greater than 1 Gohm in parallel with 2 pF.
Model 2700: Preamplifier model 056-852. The input impedance
is greater than 1 Gohm in parallel with 47 pF.
Polarization (1700 only):
Regulated 200 V DC within 2% for use with air- condenser microphones. The voltage must be switched off when using pre-polarized (electret) condenser microphones.
The input impedance is 1 Megohm in series with 0.1 MFD. The maximum sinusoidal input voltage is 10V RMS.
3.16 V RMS at full scale (60 dB). (3.8 V RMS maximum) The output impedance is 3.2K ohms. Connected equipment should be at least 10K ohms. The output can be shorted without damaging the meter or changing the meter reading.
0 to 1.00V DC; 60 dB span. Each 0.167V change equals 10 dB. Connected equipment should be at least 10K ohms. The output can be shorted without damaging the meter or changing the meter reading.
4 Hz (-3dB) to 50 kHz (-3dB) on linear weighting, meter only. (Subject to microphone limitations.)
60 to 120 dB Range setting
0o when using a Free Field Microphone. Sound is arriving from directly in front of the microphone diaphragm.
Detector Pulse Range:
Detector Measuring Range:
From 0 dB to 40 dB on the painted scale (when measuring a signal with a 20 dB Crest Factor). The extra 20 dB (40 to 60) on top of the measuring range produces the 20 dB Crest Factor capability.
Primary Indicator Range / Linearity Range:
60 dB (The range as indicated by both the dB RANGE switch and the painted 60 dB scale.) Tested with a sinusoidal signal input.
Inside the Primary Indicator Range. It is tested on the Reference Range (60 to 120 dB) with a sinusoidal input signal. Tolerance is +/- 0.7 dB referenced to 94 dB for model 1700, +/- 1.0 dB for model 2700.
OL appearing in the display indicates overload.
Referenced from the Reference Range and the Reference SPL (+34 dB on the painted meter scale).
Model 1700: Within 0.5 dB from 31.5 Hz to 8 kHz. Within 1.0
dB from 20 Hz to 12.5 kHz.
Model 2700: Within 0.7 dB from 31.5 Hz to 8 kHz.
Model 1700 : Within 0.5 dB at 25oC;
Model 2700 within 0.7 dB at 25oC.
Both models: Within 1.0 dB over the temperature range of -10