sw series impedance tube solutions - scantek...

SW Series Impedance Tube Solutions

BSWA SW series Impedance Tubes can accu-rately measure sound absorption coe�-cients and impedance according to ISO or ASTM standards. They also support the sound transmission loss measurements based on the Transfer Function Method using four microphones.

BSWA o�ers complete set of Impedance Tube systems that include:

• Tubes with built-in loudspeakers• Sample holders for absorption measurements• Extension tubes for transmission loss measurements• Microphones/Cables• Microphone Calibrator• DAQ hardware/Ampli�ers

Impedance Tubes

The SW series Impedance Tubes are specially designed to not only work with precut samples, but also for direct use in the �eld.

The small size and durable aluminum construction make it easy to be transported and used for estimating the properties of walls, ceilings, installed building materials, road surfaces, di�erent ground surfaces, interiors of vehi-cles, etc.

The inner diameter of each tube corresponds to the e�ective measurement frequency range. A larger diameter tube is suitable for measurements in the lower frequencies while a small diameter tube can measure in the higher frequencies. The diameter of the tube also indicates the diameter of the samples needed for measurements when placed inside the sample holders.

version 121530

Measurement Capabilities and Standards

Model Number SW470 SW230 SW420 SW477 SW433 SW422 Tube Diameter 30mm 60mm 100mm 30mm 60mm 100mm Measurement Frequency (Hz) 1000 - 6300 100-2500 63-1600 1000-6300 100-2500 63-1600

*Theoretical Measurement Frequency (Hz) 760-6640 100-3320 60-1930 760-6640 100-3320 60-1930

Number of Microphones 2 2 2 4 4 4 Measurement Capability Absorption Coefficient Yes Yes Yes Yes Yes Yes Reflection Coefficient Yes Yes Yes Yes Yes Yes Impedance (complex) Yes Yes Yes Yes Yes Yes Admittance (complex) Yes Yes Yes Yes Yes Yes Reflection Coefficient (Complex) Yes Yes Yes Yes Yes Yes

1/n Octave Absorption Coefficient Yes Yes Yes Yes Yes Yes

Transfer Function Yes Yes Yes Yes Yes Yes Transmission Loss - - - Yes Yes Yes G11, G12, G13, G14 Transfer Function - - - Yes Yes Yes

1/n Octave Transmission Loss - - - Yes Yes Yes

Available Impedance Tube Systems Conforming to the ISO standard and transfer function using 4 microhones method

The SW series impedance tubes all use the transfer function method for absorption and transmission loss testing.

The systems are available in two di�erent designs conforming to either ISO or ASTM test standards. Impedance tubes designed according to ASTM speci�ca-tions can measure acoustic absorption according to ASTM E1050 and trans-mission loss according to ASTM E2611.

Impedance tubes designed according to ISO speci�cations can measure acoustic absorption according to ISO10534-2. As an ISO standard for transmis-sion loss testing does not exist, a transfer function using 4 microphones method is used.

The main di�erence between systems designed in accordance to ISO or ASTM standards is the location of the microphone holders. Furthermore, an addi-tional sample holder is also provided for systems conforming to the ASTM E2611 transmission loss standard.

The following tables display various models available for systems conforming to ISO and ASTM test standards:

BSWA 1/4’’ MPA416 microphones, which have excellent phase matches, are ideal for impedance applications. The microphones are directly connected to optional 2-channel MC3522 or 4-channel MC3242 data acquisition hardware using BNC-to-SMB cables.

BSWA CA115 microphone calibrator is used to periodically calibrate the microphone signal chain of the system.

Available Impedance Tube Systems Conforming to ASTM standards

Model Number SW470 SW420 SW477 SW422 Tube Diameter 30mm 100mm 30mm 100mm Measurement Frequency (Hz) 1000 - 6100 50-1600 1000-6100 50-1600

*Theoretical Measurement Frequency (Hz) 150-6100 50-1720 150-6100 50-1720

Number of Microphones 2 2 4 4 Measurement Capability Absorption Coefficient Yes Yes Yes Yes Reflection Coefficient Yes Yes Yes Yes Impedance (complex) Yes Yes Yes Yes Admittance (complex) Yes Yes Yes Yes Reflection Coefficient (Complex) Yes Yes Yes Yes

1/n Octave Absorption Coefficient Yes Yes Yes Yes

Transmission Loss - - Yes Yes 1/n Octave Transmission Loss - - Yes Yes

Transmission Coefficient - - Yes Yes Propagation Wave Number - - Yes Yes

Data Acquisition Hardware and Ampli�ers

Microphones and Microphone Calibrator

The impedance tube systems are designed to be used with a 2-channel MC3522 or a 4-channel MC3242 data acquisition hardware cards.

The 2-channel MC3522 is ideal for absorption measurement systems where only two microphones are necessary. The MC3522 has a built in ampli�er used to power the loudspeakers of the test tubes.

The 4-channel MC3242 is required for transmission loss measurements where 4 microphones are necessary. Unlike the MC3522, the MC3242 does not contain a built-in ampli�er. As a result, a dedicated PA50 power ampli�er is used to drive the loud speaker in the impedance tube. The MC3242 is used in a complete system for both absorption and transmis-sion loss testing.

VA-LAB Software

BSWA VA-Lab software includes the Impedance Tube Module (VALab IMP) which supports sound absorption and sound transmission measurement for BSWA SW series impedance tubes.

The software works with BSWA MC3022, MC3522, MC3242 and MC3642 hardware for data acquisition and analysis. Its ease of use allows the user to quickly choose between absorption and a transmission loss measurement. All necessary parameters such as sample thickness and envi-ronmental conditions can be entered within a single window.

Results from tubes of di�ernet diameter can be combined to provide seamless results in a single frequency range.

Reports can be quick-ly generated and exported into Excel using VA-LAB's report generator.

Example of a System set up for Absorption Measurements

Example of a System set up for Absorption Measurements

Example of a System set up for Transmission Loss Meaurements (ASTM E2611)

Ease of Use

The simple design of BSWA SW series impedance tubes keeps the set up time to a minimum, ensuring that more time is spent on actual measure-ments.

Model Number Description Quantity

1 SW 470

For accurate measurement of sound absorption coefficients, 30mm inner diameter. Includes: - 30mm diameter tube with loudspeaker - 30mm diameter sample holder - Roadcase

1

2 MC 3252 USB Soundcard with 2 ICP input channels and 1 output channel; with built-in power amplifier of 20W 1 3 MPA 416 1/4" microphone with ICP Preamp 2 4 CBS005 BNC to SMB cables, 5m, to connect MPA416 to MC3522 2 5 CAA002 Banana cable to connect MC3522 to the speaker of the impedance tube (2m) 1 6 CA115 1000Hz, 114dB calibrator, Type 2, with adaptor for 1/2'' and 1/4'' microphones 1 7 VA-Lab2 BASIC Base software for measurement of noise and vibration, used for 2 channels 1

8 VA-Lab2 IMP-AT Software for measurement of material impedance values (2 mics are needed) , for measurement of Transfer Function and the calculation of sound impedance coefficients and sound impedance 1


1 SW 230

For accurate measurement of sound absorption coefficients, 60mm inner diameter. Includes: - 60mm diameter tube with loudspeaker - 60mm diameter sample holder - Roadcase

1



Complete Systems for Absorption Measurements


1

SW 420 For accurate measurement of sound absorption coefficients, 100mm inner diameter. Includes: - 100mm diameter tube with loudspeaker - 100mm diameter sample holder - Roadcase

1



The following tables provide information on complete impedance tube systems for acoustic absorption measurements. Tubes of di�erent diam-ter can be combined to create a system for desired test frequency range.


1 SW 477

For accurate measurement of sound absorption coefficients and transmission loss, 30mm inner diameter. Includes: - 30mm diameter tube with loudspeaker - 30mm diameter sample holder - 30mm diameter extension tube - Roadcase

1

2 PA50 Power Amplifier of 50W 1

3 MC 3242 DAQ card with 4 ICP input channels and 2 signal output channels, USB power supply connected with laptop 1

4 MPA 416 1/4" microphone with ICP Preamp 4 5 CBB005 BNC to BNC cables, 5m, to connect PA50 to MC3242 1 6 CBS005 BNC to SMB cables, 5m, to connect MPA416 to MC3242 4 7 CAA002 Banana cable to connect MC3522 to the speaker of the impedance tube (2m) 1 8 CA115 1000Hz, 114dB calibrator, Type 2, with adaptor for 1/2'' and 1/4'' microphones 1 9 VA-Lab4 BASIC Base software for measurement of noise and vibration, used for 4 channels 1



1 SW 433


1






1 SW 422


1





Complete Systems for Absorption and Transmission Loss Measurements

The following tables provide information on complete impedance tube systems for acoustic absorption and transmission loss measurements. Tubes of di�erent diamter can be combined to create a system for desired test frequency range.

Technical Speci�cations

PA50 Amplifier

Input 1 Channel, BNC Connector Output 1 Channel, Banana Connectors (2) Power 110V Power Supply Rated output power 50W (8Ω) Max Instantaneous Power 135W (8Ω) THD (Total Harmonic Distortion)

0.1% (20Hz – 20kHz)

Signal to Noise Ratio (SNR) ≥ 90dB Temperature -10°C to 40°C Humidity 0 to 98% RH Dimensions 10.5” (270mm) x 8.5” (220mm) x 4.3” (110mm) Weight 7 lbs. (3.5 kg) Includes Case, Power Supply Cable, Manual, Test Report

MC3522 DAQ with built-in amplifier MC3242 DAQ

Input 2 Channels, BNC Connector 4 Channels, BNC Connector Input Channel Type ICP® (4 mA) ICP® (4 mA) A/D Converter 16 Bits 24 Bits Max. Sampling Frequency 44.1 kHz 50 kHz Cross Talk: >80dB >80dB Frequency Response (Ref: 250 Hz, + 0.5dB/-1.0 dB)

20Hz – 20kHz 20Hz – 20kHz

Total Harmonic Distortion <0.01% <0.01% Measurement Range (with MPA416 microphone)

35-118 dBA 30-127 dBA

Max. Input Voltage 1 Vrms 5 Vrms Output 1 Channel, Banana Connectors (2) or

BNC Connector 2 Channels, BNC Connector

Output Frequency Range 20Hz – 20kHz 20Hz – 20kHz Max Output Voltage 1Vrms 1Vrms Max Output Power 20W - Temperature -10°C to 40°C -10°C to 40°C Humidity 0 to 98% RH 0 to 98% RH Dimensions 11” (285mm) x 8” (200mm) x 4”

(100mm) 10” (260mm) x 6” (160mm) x 5.5” (145mm)

Weight 4.8 lbs (2.2 KG) 3.3 lbs. (1.5 Kg) Includes Case, Power Supply Cable, USB Cable,

Manual, Test Report Case, Power Supply Cable, USB Cable, Manual, Test Report

Technical Speci�cations

CA115 Calibrator

Standard IEC60942:2003 Class 2, ANSI

S1.40-1984, GB/T 15173-1994 Sound Pressure Level 94.0dB/114.0 dB ±0.3 dB Frequency 1000Hz ±0.5% Microphone Diameter According to IEC61094-4: 1/2” & 1/4” Harmonic Distortion <2% Stabilization Time: <10 s Equivalent Free-field Level -0.2 dB for 1/2” Microphones Equivalent Random Incidence Level

+0.0 dB for 1/2”, 1/4”

Reference Conditions Ambient Temperature: 25°C (77°F) / Ambient Pressure: 101.3 kPa / Humidity: 55% RH / Effective Load Volume: 250 mm3

Environmental Conditions Temperature: -10°C-50°C (14°F -122°F) Pressure: 65 kPa to 108 kPa Humidity: 10 to 90%RH (non-condensing)

Power Supply Batteries: 1.5 V LR6 (AA battery) × 2 Lifetime: Typically 40 hours with alkaline batteries at 25°C (77°F)

Dimension (mm) 48 × 70 × 70 Weight 180 g, including batteries Includes Calibration Certificate

MPA 416 Microphone

Diameter ¼” Standards (IEC61672) Class I Microphone Integrated Optimized Free Field Preamplifier Integrated Frequency Response (Hz) 20Hz – 20kHz Open-circuit Sensitivity (mV/Pa) (±2dB)

50

Output Impedance (Ω) < 110 Dynamic Range 29 – 127 dBA Inherent Noise (dBA) < 29 dBA Operating Temperature (°C) -10 ~ 50 Operating Humidity (RH) 0 to 95% RH Temperature Coefficient (dB/°C) 15 ~ 35 °C: < ±0.3 dB; 0 ~ 40 °C:

< ±1.5 dB; -10 ~ 50 °C: < ±3.0 dB; with 1000Hz, at reference

Humidity Coefficient (dB/%RH) 20% ~ 90% RH: < ±0.8 dB with 1000Hz, at reference temperature 23 °C, Humidity 50% RH

Pressure Coefficient (250 Hz) (dB/kPa)

-0.06

Length (mm) 61 Input Connector SMB Includes Calibration Certificate, Case

BSWA is distributed in the U.S.A. by:

Scantek, Inc.www.ScantekInc.com

sw series impedance tube solutions - scantek...

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