JTS SIEM-121R | UHF Wireless In-Ear Monitor Receiver | 60mW Output with 8+ Hour Battery Life

JTS SIEM-121R Receiver  (JTS IEM Siam 121 Receiver)

UHF Wireless In-Ear Monitor Bodypack Receiver

The JTS SIEM-121R is a compact UHF PLL wireless in-ear monitor bodypack receiver designed to expand an existing JTS SIEM-121 wireless monitoring system. Compatible with the SIEM-121T transmitter on matching operating frequencies, this receiver allows an additional performer to monitor audio wirelessly without purchasing another complete transmitter system. With a 60mW earphone output, stereo/mono operation, and over 8 hours of battery life, it provides a practical monitoring solution for musicians, vocalists, and live sound applications.

JTS SIEM-121R Competitive Differences

• Expandable Wireless Monitoring: Add another bodypack receiver to a compatible SIEM-121T transmitter setup without requiring a second transmitter.
• Stereo and Mono Monitoring: Supports stereo monitoring or mono operation, including configurations that allow two performers to monitor separate mono mixes from one compatible transmitter.
• 60mW Earphone Output: Provides personal monitoring output through a standard 3.5mm stereo headphone connection.
• Over 8 Hours of Battery Life: Operates using two AA batteries or compatible NiMH rechargeable batteries.
• Informative LCD Display: Displays RF and audio levels, battery status, frequency, group/channel settings, and additional receiver functions.
• Compact and Lightweight: Weighs approximately 4.59 oz (130 g) without batteries for convenient bodypack use during performances.
• Integrated Monitoring Controls: Includes HF booster, limiter, key-lock functionality, and Remoset ID display.

JTS SIEM-121R Description

The JTS SIEM-121R is designed for performers and audio technicians who need to expand an existing SIEM-121 wireless in-ear monitoring system. By adding an additional receiver, more performers can access wireless monitoring from a compatible SIEM-121T transmitter. Depending on the transmitter's configuration, the system can support stereo monitoring or separate mono mixes for two performers, making it useful for bands, vocalists, houses of worship, and live stage productions.

The receiver features a 60mW earphone output with a minimum supported load impedance of 16 ohms. Its standard 3.5mm stereo output accommodates compatible in-ear monitoring earphones. Selectable stereo and mono operation provides flexibility for different monitoring requirements, while the integrated HF booster and limiter offer additional audio monitoring controls.

An integrated LCD provides convenient access to essential operating information, including RF signal level, AF audio level, battery status, operating frequency, and selected group/channel. The display also supports user names, key-lock status, stereo/mono settings, and Remoset ID information, helping performers and technicians manage receiver settings during live events.

Designed for portable operation, the SIEM-121R measures just 2.56 x 0.79 x 3.74 inches and weighs approximately 4.59 ounces without batteries. It operates for over 8 hours using two standard AA batteries or compatible NiMH rechargeable batteries, providing extended monitoring capability during rehearsals, performances, and live productions.

SIEM-121R Features

• UHF PLL wireless in-ear monitor bodypack receiver
• Designed for use with compatible JTS SIEM-121T wireless transmitters
• Allows expansion of an existing SIEM-121 monitoring system
• Supports stereo and mono in-ear monitoring
• Supports separate mono monitoring mixes when configured with a compatible transmitter
• 60mW earphone output
• 3.5mm stereo earphone output connector
• Minimum load impedance of 16 ohms
• LCD displays RF and AF signal levels
• Battery level indicator for monitoring remaining power
• Displays operating frequency and group/channel selection
• User-programmable name display
• HF booster and limiter functions
• Key-lock functionality helps prevent accidental adjustments
• Remoset ID display for system configuration
• Operates using two AA batteries or compatible NiMH rechargeable batteries
• Over 8 hours of operating time
• Compact, lightweight bodypack design

SIEM-121R Specifications

• Brand: JTS
• Model: SIEM-121R
• Product Type: UHF PLL Wireless In-Ear Monitor Bodypack Receiver
• Published Carrier Frequency Range: 470–960 MHz (specific operating range depends on frequency version)
• Compatible Transmitter: JTS SIEM-121T (matching frequency version required)
• Earphone Output Power: 60mW
• Minimum Load Impedance: 16 Ohms
• Audio Output Connector: 3.5mm Stereo Phone Jack
• Monitoring Modes: Stereo / Mono
• LCD Display Functions: Antenna, RF Level, AF Level, User Name, Key Lock, Battery Fuel Gauge, Stereo/Mono, HF Booster, Limiter, Group/Channel, Remoset ID, Frequency
• Battery Requirements: 2 x AA Batteries or 2 x NiMH Rechargeable Batteries
• Operating Time: Over 8 Hours
• Dimensions (W x D x H): 2.56 x 0.79 x 3.74 in (65 x 20 x 95 mm)
• Weight: 4.59 oz (130 g) Without Batteries

Note: This listing is for an additional SIEM-121R bodypack receiver only. A compatible SIEM-121T transmitter is required for wireless operation and is not included. Confirm the operating frequency version matches your existing system.