1. Introduction
The SHIDU S278 is a versatile 15W portable voice amplifier designed to provide clear and powerful sound projection for various applications such as teaching, presentations, tour guiding, and more. It features multiple playback modes, recording capabilities, and a comfortable, ergonomic design.
Figure 1: SHIDU S278 Voice Amplifier
2. Package Contents
Please check the box for the following items:
- 1 x SHIDU S278 Voice Amplifier
- 1 x Wired Headset Microphone
- 1 x Micro USB Charging Cable
- 1 x AUX Audio Cable
- 1 x Waistband
- 1 x User Manual
Figure 2: Package Contents
3. Product Overview
3.1. Controls and Ports
Figure 3: Amplifier Ports and Controls
- Front Panel: OLED Display, Mode Button (M), Rewind/Previous, Play/Pause, Fast Forward/Next, Record Button, Speaker Grille.
- Top Panel: AUX Input (3.5mm), MIC Input (3.5mm), DC 5V Charging Port (Micro USB), ON/OFF/Volume Control Slider, Retractable FM Antenna.
- Side Panel: TF Card Slot, USB Port.
3.2. Ergonomic Microphone Design
Figure 4: Wired Microphone Features
4. Setup
4.1. Charging the Amplifier
- Connect the Micro USB charging cable to the DC 5V port on the amplifier.
- Plug the other end of the cable into a suitable USB power source (e.g., wall adapter, computer USB port).
- Charge the device for approximately 3-5 hours for a full charge. The battery indicator on the OLED display will show charging status.
4.2. Wearing the Amplifier
- Attach the provided waistband to the metal loops on the sides of the amplifier.
- Adjust the waistband to comfortably wear the amplifier around your waist or neck.
4.3. Connecting the Microphone
- Plug the wired headset microphone into the MIC input port on the amplifier.
- Adjust the flexible microphone boom so that the microphone is positioned directly in front of your mouth for optimal sound pickup.
5. Operating Instructions
5.1. Power On/Off and Volume Control
- To power on the amplifier, slide the ON/OFF/Volume control switch upwards. The OLED display will light up.
- To power off, slide the switch downwards.
- To adjust the volume, rotate the ON/OFF/Volume control slider.
Figure 5: Easy Volume Control
5.2. Voice Amplification
- Ensure the wired microphone is securely connected to the MIC input.
- Turn on the amplifier and adjust the volume to a comfortable level.
- Speak clearly into the microphone. Your voice will be amplified through the speaker.
Figure 6: Voice Amplification Coverage
5.3. Mode Selection
- Press the 'M' button on the front panel to cycle through available modes: Bluetooth, FM Radio, and Audio Playback (TF/USB/AUX). The current mode will be displayed on the OLED screen.
5.4. Bluetooth Mode
- Press the 'M' button until "BLUE" appears on the display. The amplifier will announce "Bluetooth is waiting for connection".
- On your smartphone or other Bluetooth-enabled device, enable Bluetooth and search for available devices.
- Select "SHIDU S278" (or similar model name) from the list to pair.
- Once connected, you can play audio from your device through the amplifier.
Figure 7: Bluetooth Connectivity
5.5. FM Radio Mode
- Press the 'M' button until "FM" appears on the display. The amplifier will announce "FM mode".
- Extend the retractable FM antenna for better signal reception.
- Use the Previous/Next buttons to scan for radio stations. The frequency will be shown on the display.
Figure 8: FM Radio Function
5.6. Audio Playback (TF Card/USB/AUX)
- TF Card/USB: Insert a TF card or USB flash drive containing MP3 audio files into the corresponding slot. The amplifier will automatically switch to playback mode. Use the Previous/Next and Play/Pause buttons to control playback.
- AUX Mode: Connect an external audio source (e.g., computer, smartphone) to the AUX input port using the provided 3.5mm audio cable. The amplifier will function as an external speaker for the connected device.
5.7. Recording
- Ensure a TF card or USB flash drive is inserted into the amplifier.
- Press the Record button (often indicated by a circle or 'REC' icon) to start recording.
- Speak into the microphone.
- Press the Record button again to stop and save the recording.
Figure 9: One-Touch Recording
6. Specifications
| Attribute | Value |
|---|---|
| Model | S278 |
| Power Output | 15W |
| Battery | 3.7V 2500mAh Lithium Battery |
| Battery Life (Voice Amplification) | 8-12 Hours |
| Charging Time | 3-5 Hours |
| Dimensions (WxHxD) | 115*86*35mm |
| Weight | 203g - 204g |
| Material | TPU+Plastic |
| Range | 70oBa |
| Formats Supported | MP3 |
| S/N Ratio | >=70dBa |
| Distortion | <=1% |
| Frequency Response | 200HZ-18KHZ |
| Bluetooth Version | 4.2 |
| Certification | CE, RoHS |
Figure 10: Technical Parameters
7. Maintenance
- Keep the amplifier in a dry and well-ventilated area.
- Avoid dropping or subjecting the device to strong impacts.
- Do not disassemble or repair the product yourself. Contact qualified personnel for service.
- Recharge the battery when power is low to prolong battery life.
8. Troubleshooting
- No Sound/Low Volume: Check the volume control. Ensure the microphone is securely plugged in. Check the battery level and recharge if necessary.
- Howling/Feedback: Increase the distance between the microphone and the speaker. Reduce the volume. Ensure the microphone is not pointing directly at the speaker.
- Bluetooth Connection Issues: Ensure the device is in Bluetooth mode. Check that Bluetooth is enabled on your external device. Try re-pairing the devices.
- FM Radio Static: Extend the antenna fully. Move to an area with better signal reception.
- Recording Not Working: Ensure a TF card or USB drive is inserted and has sufficient available storage space.
9. User Tips
- For optimal voice amplification, position the microphone directly in front of your mouth.
- To prevent feedback (howling), maintain a distance between the microphone and the speaker, and avoid pointing the microphone directly at the speaker. Gradually increase the volume.
- If you only need voice amplification and not Bluetooth, short press the 'M' button after turning on the device to switch out of Bluetooth mode.
10. Safety Information
- Do not insert or plug connectors frequently to avoid loosening sockets or bad connections.
- Keep the product and its accessories away from children.
- Avoid exposing the device to extreme temperatures or direct sunlight.
11. Warranty and Support
For any service, repair, or support needs, please contact the local agent or the seller from whom you purchased the product. Non-professional technicians are not authorized to dismantle or repair the product, as this may void any applicable warranty.
12. Product Video Overview
Video: Overview of the SHIDU S278 Voice Amplifier and its features.
