AP - The Recognized Standard In Audio Test

Audio Precision offers three models of the SWR-2755 audio switchers, which expand the 2-channel input and output capabilities of Audio Precision 2700 series and ATS-2 audio analyzers, as well as older System One and System Two instruments.

SWR-2755 switchers replace the SWR-2122 switchers, which have been discontinued. The new switchers are entirely compatible with our current products and offer better performance at a lower price. They also may be used with any discontinued products that originally specified the SWR-2122 or SWR-122 switchers.

Built with the same feature set and solid integrity of the SWR-2122, the new SWR-2755 series bring significantly lower crosstalk (18 dB better in an unbalanced 600 Ω load; 10 dB better in a balanced 600 Ω load), a new universal power supply that automatically adjusts to all line voltages, a convenient rear-panel ground lug and full EMC and safety regulatory compliance. Manufacturing economies enable us to offer the new switchers at a significantly lower price.

Key features

• Input and output configurations enable switching of generator outputs or analyzer inputs, or both.
• Balanced and unbalanced configurations are available.
• LEDs indicate the on or off status of each channel.
• Multiple switchers can be connected to an Audio Precision analyzer, expanding the system capability to as many as 192 inputs and outputs.
• Low inter-channel crosstalk, less than –150 dB at 20 kHz in the balanced configurations.
• All switchers are one rack unit (RU) high (1.75"). switchers can be used on the bench or rack mounted with an optional rack mount adapter kit.

Specs

Electrical Characteristics

• Max Voltage Rating 200 Vpk, 160 Vrms
• Max Signal Power 5 W or 200 mA
• Crosstalk
  • Balanced 600 ohm load 
    –150 dB @ 20 kHz
    –136 dB @ 100 kHz
  • Unbalanced 600 ohm load
    –138 dB @ 20 kHz
    –124 dB @ 100 kHz
• Series resistance typically <0.3 ohm per side
• Shunt capacitance typically <90 pF, from signal path to chassis (100 nF from BNC shell to chassis on U versions).
• Reverse termination 604 ohm, 250 mW maximum

General Characteristics

• Power Requirements 90–250 Vac, 50-60 Hz, via external dc supply module
• Temperature Range
  Operating 0°C to +50°C
  Storage –40°C to +75°C
• Humidity 80% RH to +40°C, (non-condensing)
• Dimensions 16.5 x 1.75 x 10.5 inches [41.9 x 4.4 x 26.7 cm]
• Weight Approximately 9.9 Ibs [4.5 kg]
• Regulatory Compliance
  • EMC complies with FCC Part 15 Subpart J (class B), 89/336/EEC, 92/31/EEC, and 93/68/EEC, EN 50081-1 (1992) Emissions Class B, EN-50082-1 (1992) Immunity.
  • Safety complies with 73/23/EEC, 93/68/EEC, EN6010-1 (1903)— IEC 1010-1 (1990) + Amendment 1 (1992) + Amendment 2 (1995).
    Installation category II—Pollution Degree 2.
  • External Power Supply AP part number 4540.0020 complies with IEC 60950:1991+A1+A2+A3+A4, UL 950 Third Edition E183744, CSA C22.2 No. 950.
  • External Power Supply AP part number 4540.0051 complies with IEC 60950:1991, UL60950 Third Edition E199447, CSA C22.2 No. 60950, PSE J60950:1998, NOM-001-SCFI-1993.

  Options

  SWR-2755M Output Switcher

  • 12 X 2 configuration
  • Can route either of the two generator output channels (A & B) to any of 12 channels
  • Up to 16 units can be cascaded to allow up to 192 channels to be accessed
  • XLR connectors for balanced signals or, using adapters, unbalanced signals
  • Complement mode allows all but one channel to be driven while measuring the undriven channel for worse case crosstalk on multichannel devices

  SWR-2755F Input Switcher

  • 12 X 2 configuration
  • Can route either of the two analyzer input channels (A & B) from any of the 12 channels
  • Up to 16 units can be cascaded to allow up to 192 channels to be accessed
  • XLR connectors for balanced signals or, using adapters, unbalanced signals

  SWR-2755U Unbalanced Switcher

  • 12 x 2 configuration
  • Can be used as either an input or output switcher (by dip switch on rear panel)
  • Up to 16 units can be cascaded to allow up to 192 channels to be accessed
  • Floating BNC connectors for unbalanced signals prevent ground loops