Peavey ALS 72.1 Mhz Assisted Listening System Transmitter And Four Receivers With Ear Buds Frequency Response 100Hz - 15 KHz, +/- 3dB Features•Peavey ALS 72.1 Mhz Assisted Listening System Transmitter And Four Receivers With Ear Buds•Frequency Response 100Hz - 15 KHz, +/- 3dB•Signal-to- Noise Ratio 60dB•Total Harmonic Distortion <0.5%•RF Carrier Frequency between 72-76 MHz•Frequency Stability +/- 0.005%•Modulation FM +/- 75KHz max•Operating Range Up to 300 ft. line of sight•DescriptionTransmitter• Mic Input - Connector: ¼" phone jack, Impedance: low impedance, unbalanced, with 9V DC at 1 mA for condenser mic.• Line Input - Connector: ¼" phone jack, Impedance: 100 K, unbalanced.• Power Output - 80,000 uV @ 3 meters.• Controls - Power ON/OFF, audio input gain adjust• Indicators - Power ON LED, Audio Modulation LED• Antenna - Permanently mounted telescoping whip• Power Requirement - 9V DC, regulated @ 200 mA, AC/DC adapter provided• Dimensions - 220 x 121 x 43mm• Weight - 19.5 oz (600g)Receiver• Controls - Combination VOLUME/ON-OFF wheel• Audio Output - 250 mW max into 16 ohms• Connectors - 3.5mm mini jack for earphone output• Earphones - Mini binaural ear buds• Antenna - Integral with earphone cord• Indicators - LED power on indicator• Sensitivity - 2 uV for 12 dB Sinad with squelch defeated, Squelches at 10 uV for min. 50 dB S-N ratio• Mute Threshold - 8-10 uV• Power Requirement - (2) AA Batteries• Battery Life - 17-20 hours with alkaline battery• Dimensions - 110 x 60 x 20 mm• Weight 2.75 oz without batteries (80g)