To Next PageTo Next PageWhat to do if my Yamaha YST-SW215 has no sound?
If your Yamaha Subwoofer isn't producing any sound, first, make sure the volume isn't set to the minimum; if it is, increase it. Also, ensure that the speaker cables are securely connected.
How to fix too low sound level on Yamaha YST-SW215 Subwoofer?
If the sound level from your Yamaha Subwoofer is too low, ensure that the speaker cables are connected correctly, matching L (left) to L, R (right) to R, “+” to “+” and “–” to “–.”
Why Yamaha YST-SW215 power is not supplied?
If the Yamaha Subwoofer's power isn't turning on even when the STANDBY/ON button is in the ON position, check that the power plug is securely connected. Also, verify that the POWER switch is set to the ON position.
Essential information for authorized service personnel, including safety and product integrity warnings.
Guidelines for technicians on critical components, leakage current testing, and safety precautions.
Visual guide to the internal layout and components of the subwoofer.
Detailed technical data including output power, input sensitivity, frequency response, and power consumption.
Diagrams illustrating rear panel connectivity and controls for various model variants.
Step-by-step instructions for safely disassembling the subwoofer unit.
Procedure to verify the auto standby function's performance and indicator lights.
High-level functional overview of the subwoofer system's interconnected modules.
Foil side layouts and semiconductor locations for various main PCBs.
Detailed electrical schematic illustrating the circuit design for troubleshooting.
Comprehensive list of electrical and mechanical components, and their part numbers.
This document serves as a comprehensive service manual for the YST-SW215 Subwoofer System, providing essential information for authorized Yamaha Retailers and their service personnel. It outlines the device's function, usage features, and critical maintenance procedures, emphasizing safety and proper handling.
The YST-SW215 is a subwoofer system designed to enhance audio experiences by reproducing low-frequency sounds. Its core function is to deliver deep, resonant bass, complementing a full-range audio setup. The system incorporates advanced Yamaha Active Servo Technology, which optimizes the interaction between the amplifier and the speaker cone to achieve powerful and accurate bass reproduction. This technology allows the subwoofer to maintain precise control over the speaker's movement, even at high volumes, preventing distortion and ensuring a clear, impactful low-end.
For usage, the YST-SW215 offers several features to tailor the audio output to individual preferences and room acoustics. On the front panel, users will find a STANDBY/ON switch, allowing for easy power management. A B.A.S.S. (Bass Action Selector System) switch provides options to adjust the bass characteristics, offering different modes for various listening scenarios, such as music or movies. A VOLUME control allows for precise adjustment of the subwoofer's output level, ensuring it blends seamlessly with other speakers in the system. Additionally, a HIGH CUT control enables users to set the upper frequency limit of the subwoofer, preventing it from reproducing frequencies that should be handled by the main speakers. An LED indicator provides visual feedback on the system's status.
The rear panel of the YST-SW215 offers further customization and connectivity options. A POWER switch provides the main power control for the unit. An AUTO STANDBY switch allows the subwoofer to automatically enter a low-power standby mode when no audio signal is detected for a period, conserving energy. This feature can be set to HIGH, LOW, or OFF, depending on the user's preference for sensitivity and power saving. A PHASE switch (NORM/REV) helps to align the subwoofer's output with the main speakers, ensuring that bass frequencies arrive in phase, which is crucial for optimal sound quality and impact. For models designed for specific regions (R, T, K models), a VOLTAGE SELECTOR is included, allowing the unit to be adapted to different local power supplies.
Connectivity options on the rear panel include speaker terminals for INPUT1, allowing connection to an amplifier's speaker outputs, and RCA pin jacks for INPUT2, providing a line-level input for direct connection to an audio source or receiver. These diverse input options ensure compatibility with a wide range of audio systems.
Maintenance features are primarily focused on ensuring the safety and longevity of the YST-SW215. The manual highlights critical components that are marked with a special symbol (▲) and must be replaced with parts having identical specifications to those originally installed. This is crucial for maintaining the product's safety and performance standards. For 120V models, a leakage current measurement is required after service to verify that all exposed conductive surfaces are properly insulated from supply circuits, with a maximum leakage current of 0.5mA. The manual also advises testing for leakage with the AC plug in both polarities.
A "CAUTION" notice specifically addresses the fuse (F1), stating that for continued protection against the risk of fire, it must be replaced only with the same type (4A, 125V fuse). This emphasizes the importance of using correct replacement parts.
The manual also includes a "WARNING: CHEMICAL CONTENT NOTICE!" which informs users and service personnel that the solder used in the product contains LEAD, and other components may contain traces of chemicals known to cause cancer or reproductive harm. It strongly advises against placing electrical/electronic or plastic components in the mouth and recommends avoiding prolonged, unprotected contact between solder and skin. When soldering, proper ventilation is advised to avoid inhaling fumes or exposing eyes to solder/flux vapor. Washing hands after contact with solder or components inside the enclosure is also recommended before handling food.
For disassembly and part replacement, the manual provides detailed procedures, stressing the importance of turning the unit OFF and discharging any static electricity from the body by grounding oneself to the unit's ground buss. Rechecking all work before applying power to the unit is also emphasized to prevent damage or injury.
A specific procedure for confirming auto standby operation is outlined, which involves setting the rear panel power switch to OFF, connecting a 10 kΩ resistor across R252 on the MAIN P.C.B. (3) to shorten the check time, connecting a signal generator to the L/MONO terminal with a 100 Hz, 8 mV sine wave, and then turning the power switch ON. The procedure details how to test the AUTO STANDBY switch in both LOW and HIGH positions, observing the LED indicator's behavior (green for ON, changing to red after 5-10 seconds in LOW mode, and remaining green in HIGH mode). After confirmation, the 10 kΩ resistor must be disconnected.
The manual also includes a "P.C.B. Checking" section, which instructs service personnel to reconnect all connectors removed during disassembly to their original positions and to place the rear panel assembly on a protective cloth before checking.
Overall, the YST-SW215 Subwoofer System is designed for robust performance and user-friendly operation, with a strong emphasis on safety and proper service procedures to ensure its long-term reliability and optimal sound delivery.
General| Power Output | 100 Watts |
|---|---|
| Frequency Response | 28 Hz - 200 Hz |
| Type | Active |
| Weight | 24.3 lbs |
| Technology | Advanced YST |
| Driver Size | 8" cone |
