Audio-Technica ATW-901A/L System 9 Series Wireless Lavalier Microphone System

Enjoy Worry-Free Pristine Sound With The Audio-Technica System 9 Wireless Lavalier Microphone System

Audio-Technica's System 9 is a four-channel frequency-agile wireless system designed to provide rock-solid performance along with easy setup and clear, natural sound quality. Featuring sleek, stackable, contemporary styling, System 9 has compatible options for handheld, headworn, guitar, and body-pack configurations as well. The system also offers four compatible user-switchable VHF channels (169.505, 170.245, 171.045, and 171.905 MHz)

This System 9 configuration includes the ATW-R900a receiver and ATW-T901a body-pack transmitter with a MT830 omnidirectional lavalier microphone. The ATW-R900a is a non-diversity, single-channel receiver with advanced dipole antenna design for extended operating range, which improves operation by providing a ground element in addition to the usual signal element. The ATW-R900a also offers volume control along with AF Peak, RF and Power indicator lights.

Designed to be worn as a lavalier or hidden in loose clothing or in the hair, the MT830 omnidirectional condenser microphone provides high intelligibility for lecturers, stage/TV performers, and singers. The mic's wide-range capability ensures clean, accurate reproduction.

• Easy operation and clear, natural sound quality
• 4 selectable frequency-coordinated VHF channels
• Balanced XLR and unbalanced 1/4" output jacks enable use with a wide variety of audio gear
• Reliable performance and durable construction
• Advanced dipole antenna system for extended operating range

SPECIFICATIONS

System

• Operating Frequencies: VHF highband, 169 MHz to 172 MHz
• Modulation Mode: FM
• Maximum Deviation: +/-10 kHz
• Frequency Response: 80 Hz to 13 kHz
• Operating Range: 200' (60 m) typical (Open range environment with no interfering signals)
• Total Harmonic Distortion: less than 1% (at 1 kHz, +/-10 kHz deviation)
• Operating Temperature Range: 40° F (4° C) to 110° F (43° C) Battery performance may be reduced at very low temperatures

ATW-R900a Receiver

• Receiving System: Non-diversity, single-channel, dual antenna system
• Image Rejection: 50 dB minimum
• RF Sensitivity: 20 dBuV at 60 dB S/N ratio (50 ohms termination)
• Power Supply: 100-240V AC (50/60 Hz) to 12V DC .5A (center positive) switched mode external power supply
• Dimensions: 7.48 (190.0) W x 1.82 (46.2) H x 5.06" (128.5 mm) D
• Weight: 12.0 oz (337 g)
• Accessories Included: Power supply
• Nominal Output Level
• XLR, balanced: 350 mV (1 kHz modulation, 10 kHz deviation, 100k ohm load)
• 1/4" (6.3 mm), unbalanced: 700 mV (1 kHz modulation, 10 kHz deviation, 100k ohm load)

ATW-T901a Body-Pack Transmitter

• RF Power Output: 10 mW
• Battery Life: 8 hours (alkaline) Depending on battery type and use pattern
• Battery Type: Two 1.5V AA (not included)
• Dimensions: 2.76 (70.2) W x 4.08 (103.7) H x 0.98" (24.9 mm) D
• Input Connections: Four-pin Locking Connector
• Pin 1: GND
• Pin 2: INST INPUT
• Pin 3: MIC INPUT
• Pin 4: DC BIAS +9V
• Net Weight: 2.8 oz (80.0 g) without batteries
• Spurious Emissions: Following federal and national regulations

MT830 Omnidirectional Lavalier Microphone

• Element: Fixed-charge back plate, permanently polarized condenser
• Polar Pattern: Omnidirectional
• Frequency Response: 30 - 20,000 Hz
• Open Circuit Sensitivity: -37 dB (14.1 mV) re 1V at 1 Pa
• Maximum Input Sound Level: 135 dB SPL, 1 kHz at 1% T.H.D.
• Signal-to-Noise Ratio: 67 dB, 1 kHz at 1 Pa
• Cable: 7.6 m (25') long (permanently attached to microphone), 2.5 mm (0.10") diameter, 2-conductor, shielded cable with TA3F-type output connector
• Dimensions: 15.8 mm (0.62") long, 8.3 mm (0.33") wide, 5.0 mm (0.19") thick
• Accessories Included: AT8420 clothing clip; AT8130 windscreens

We are Chuck Levin's Washington Music Center

Since 1958, Chuck Levin’s Washington Music Center has been the trusted destination for musicians and audio professionals across Maryland, Virginia, and Washington, D.C. Family-owned and operated, our legendary music store delivers Everything in Music®—from instruments and recording gear to pro audio, rentals, and repair services.

Our team of musicians and industry experts lives and breathes gear, helping you build the perfect setup for your next performance, studio session, or installation. As an authorized dealer for top brands, we also offer our award-winning CHUCKSCLUSIVE line—exclusive, limited-edition instruments and collaborations recognized with the NAMM Top 100 Dealer Innovation Award for redefining what a music retail experience can be.

Chuck Levin’s isn’t just a store—it’s a community built by players, engineers, and creators who share a lifelong passion for sound. Stop by our legendary Wheaton, MD showroom or contact us anytime for expert advice, product questions, or the best possible deal on your next piece of gear.