Debra Audio ST-102 Stereo Wireless IEM System User Manual

About Debra Audio

Debra Audio is dedicated to developing professional audio equipment. The ST-102 system is the result of two years of research and development, utilizing a new digital chip and UHF transmission for enhanced efficiency and stability. It is presented as a high-cost-performance option for both entry-level and professional users.

Product Overview

The Debra Audio ST-102 is a professional stereo in-ear wireless monitoring system. It features a new digital chip, UHF signal transmission for stable operation, clear sound, and ultra-low white noise. It offers a mono/stereo switch for versatile use and Bluetooth 5.0 for convenient wireless music playback. Its wide signal range makes it ideal for stage performances, studios, and band rehearsals.

Hearing Safety Warning

WARNING: LISTENING TO AUDIO AT EXCESSIVE VOLUMES CAN CAUSE PERMANENT HEARING DAMAGE. USE AS LOW A VOLUME AS POSSIBLE. Overexposure to excessive sound levels can damage your ears, resulting in permanent noise-induced hearing loss (NIHL). Follow Occupational Safety and Health Administration (OSHA) guidelines for maximum time exposure to sound pressure levels.

Key Features

• True stereo wireless in-ear monitoring, with mono switching capability.
• Bluetooth 5.0 for lossless music transmission and high sound reproduction.
• High-performance digital chip delivering high-fidelity sound and ultra-low background noise.
• UHF transmission with an 80m operating range, extendable up to 300m in open environments.
• Transmitter equipped with a multifunctional LCD digital display.
• Portable and lightweight receiver featuring 2 output interfaces (3.5mm).
• Interface supports multiple input modes (XLR, 6.35mm, 3.5mm).

Technical Parameters

Wireless Stereo System

• Carrier frequency range: 560-590MHz / 640-664.75MHz
• Audio sampling depth: 24bit, 44.1kHz
• Signal delay: 0.3ms
• Number of wireless channels: 100
• Modulation method: GFSK
• Audio Frequency Response: 20Hz - 18000Hz
• Comprehensive T.H.D.: <0.1%
• Separation: 75dB
• Audio SNR: 85dB
• Dynamic range: 95dB
• Effective use distance: 80 meters (open environment)

Transmitter

• Frequency error: ≤10ppm
• Transmission power: 10mW
• Operating current: 160mA
• Power supply: 12V 500mA adapter
• Audio input: 3.5mm, 6.5mm, XLR

Receiver

• Frequency error: ≤10ppm
• Receiving sensitivity: <-95dBm
• Power supply: 2x AA batteries
• Operating current: 130mA
• Audio output: 1 stereo headphone output, 1 audio output

Transmitter Description

Front Panel

Diagram of the transmitter front panel:

• 1. Wired headphone jack (3.5mm TRS)
• 2. Wired headset volume control
• 3. Set button: Short press to enable [IR] pairing; Long press for 3 seconds to turn [Bluetooth] ON/OFF.
• 4. LCD information display
• 5. Frequency adjustment knob: Rotate left/right to adjust frequency. Press to switch between Stereo/Mono modes.
• 6. Power switch

Rear Panel

Diagram of the transmitter rear panel:

• 7. [IR] frequency matching indicator/port (for receiver connection)
• 8. [Bluetooth] indicator light: Flashing = waiting for connection; Solid light = successful connection; OFF = [Bluetooth] disabled.
• 9. Power interface
• 10. 6.5mm output
• 11. 3.5mm input
• 12. XLR/6.5mm mono input
• 13. Input volume control
• 14. Antenna interface

Receiver Description

Front Panel

Diagram of the receiver front panel:

• 1. Headphone jack (3.5mm TRS)
• 2. Audio output interface
• 3. Knob switch: Functions as power switch and volume control.
• 4. Signal Antenna
• 5. LCD information display
• 6. [IR] frequency matching position
• 7. Stereo/Mono switching indicator (transmitter status takes priority)

Back Panel

Diagram of the receiver back panel:

• 8. Battery compartment: Requires 2 AA batteries.
• 9. Back clip for wearing.

Operation Instructions

How to Switch Frequency & Match Receiver

1. Step 1: Select the desired frequency by rotating the frequency adjustment knob left or right on the transmitter.
2. Step 2: Press the frequency adjustment knob to confirm the selected frequency.
3. Step 3: Press the SET button on the transmitter. The LCD will display "IR---".
4. Step 4: Align the [IR] position on the receiver with the [IR] indicator on the transmitter to establish the connection.

How to Choose Stereo/Mono Mode

To switch between Stereo and Mono modes: First, press the frequency adjustment knob. Then, rotate the knob left or right to select either Stereo or Mono mode. Finally, press the knob again to confirm the selection. The transmitter's status takes priority.

[Bluetooth] Connection & Wireless Music Playback

To turn [Bluetooth] ON/OFF: Long press the SET button (3 seconds) on the transmitter.

To connect: Turn on the [Bluetooth] function on your mobile phone. Search for the device named "ST-102" and select it. The [Bluetooth] indicator light on the transmitter will illuminate solid once the connection is successful.

Usage Methods & Application Scenarios

Single System for an Individual Performer

This setup is for solo performances or when only one person in a group needs wireless monitoring. The system can be expanded by adding more bodypack receivers paired to the same transmitter.

Configuration: A mixer output connects to the ST-102 transmitter. A receiver is connected to headphones.

Multiple Receivers with Shared Mixes

Each performer can set their receiver to Mix mode, or the stereo transmitter can be set to Stereo. The receiver defaults to stereo when powered on.

Configuration: Multiple ST-102 receivers are connected to a single ST-102 transmitter, all receiving the same audio mix from the mixer.

Multiple Transmitters with Separate Mixes

For groups with different monitoring needs, multiple ST-102 systems can be used simultaneously. Each transmitter can send a different mix. This requires a mixer with multiple monitor/aux outputs, one for each transmitter.

Configuration: Multiple ST-102 transmitters are shown, each connected to a mixer output, allowing for separate audio mixes to be sent to different performers.