1. Introduction
The KEiiD KD-240BT is a compact Class D stereo amplifier and receiver designed for high-fidelity home audio entertainment. It delivers 2x 40W RMS output and incorporates a Texas Instruments (TI) chip for enhanced performance. This unit is compatible with various passive speakers, with 6 to 8 ohm speakers recommended for optimal sound. It also features a convenient sleep timer function.
2. Key Features
- Powerful Stereo Output: 2x 40W RMS Class D amplifier, capable of driving speakers up to 200W total.
- Advanced Bluetooth 5.0: Equipped with an external antenna for stable, lossless wireless music streaming up to 65 feet (20 meters) in open areas.
- Multiple Audio Inputs: Supports Optical, SPDIF, RCA, AUX, and USB for broad compatibility with analog and digital devices (up to 16 bits/44.1 kHz).
- Microphone Input: Includes a 1/4-inch wired microphone input.
- Adjustable Sound Controls: Features independent knobs for microphone volume, echo, L/R balance, bass, treble, and master volume.
- Equalization Options: Pre-set EQ modes including Country, Pop, Jazz, Rock, Classic, and Normal.
- Digital LED Display: Provides clear visual feedback for all operations.
- Remote Control: Full-function remote for convenient operation.
- Sleep Timer Function: Customizable sleep timer from 30 to 180 minutes.
- 5-Level Safety Protection: Built-in safeguards against overload, overvoltage, overcurrent, short circuits, and self-protection for enhanced device and speaker safety.
3. Package Contents
Please check the box for the following items:
Image: Contents of the KEiiD KD-240BT package, showing the receiver, remote control, Bluetooth antenna, headphone convertor, audio cord, and power cord.
- KEiiD KD-240BT Receiver & Amplifier
- Remote Control (requires 2x AAA batteries, not included)
- Bluetooth Antenna
- 1/4" Male to 1/8" Female Headphone Convertor
- 5 ft Audio Cord
- Power Cord
- User Manual (this document)
4. Setup
4.1 Connecting Speakers
Connect your passive speakers to the Left & Right-Channel Line Out terminals on the rear panel. Ensure correct polarity (+ to + and - to -). The unit supports 4-16 ohm speakers; 6 or 8 ohm speakers are recommended for optimal performance.
4.2 Connecting Audio Sources
The KD-240BT offers multiple input options:
Image: Detailed view of the KEiiD KD-240BT rear panel, showing connections for power, Bluetooth antenna, speakers, subwoofer output, record/audio output, RCA input, optical input, S/PDIF input, and microphone input.
- Optical Input: Connect devices like TVs or CD players using an optical cable.
- S/PDIF Input: Connect devices using an S/PDIF coaxial cable.
- RCA Input (AUX): Use RCA cables to connect analog audio sources.
- USB Input: Insert a USB flash drive for playing audio files (WAV/FLAC/APE formats supported).
- Microphone Input: Connect a 1/4-inch wired microphone.
- Bluetooth Antenna: Screw the provided Bluetooth antenna into its designated port on the rear panel for optimal wireless reception.
4.3 Power Connection
Connect the provided power cord to the AC input on the rear panel of the receiver and then to a standard AC100-240V wall outlet.
Image: Diagram illustrating various input and output connections for the KEiiD KD-240BT, showing how to connect phones, pads, PCs, TV audio, CD/DVD players, turntables, and microphones via Bluetooth, USB, Optical, S/PDIF, and AUX, and outputting to passive speakers, home entertainment systems, BGM music systems, and wired headphones.
5. Operating Instructions
5.1 Power On/Off
Press the POWER button on the front panel or the remote control to turn the unit on or off.
5.2 Input Selection
Use the input selector buttons on the front panel or the remote control to switch between available audio sources: USB, Optical, SPDIF, AUX, and Bluetooth.
5.3 Bluetooth Pairing
Image: A KEiiD KD-240BT receiver next to a speaker and a smartphone, highlighting its Bluetooth 5.0 capability with an external antenna for stable, long-distance connection.
- Ensure the Bluetooth antenna is securely connected to the receiver.
- Select the Bluetooth input mode on the KD-240BT. The LED display will indicate 'BT'.
- On your Bluetooth-enabled device (smartphone, tablet, PC), go to the Bluetooth settings.
- Search for available devices and select "KEiiD KD-240BT" from the list.
- Once paired, the device will connect, and you can stream audio wirelessly.
5.4 Volume and Tone Control
- Master Volume: Adjust the overall output volume using the large MASTER knob on the front panel or the volume buttons on the remote.
- Bass/Treble: Use the BASS and TREBLE knobs to adjust the low and high frequencies of the audio output.
- Balance: Adjust the BALANCE knob to control the left and right channel output levels.
5.5 Microphone Controls
If a microphone is connected:
- MIC Volume: Adjust the microphone input level using the MIC knob.
- Echo: Adjust the echo effect for the microphone using the ECHO knob.
5.6 Equalization (EQ)
Use the EQ function on the remote control to cycle through pre-set equalization modes: Country, Pop, Jazz, Rock, Classic, and Normal. This allows you to tailor the sound profile to your preference.
5.7 Sleep Timer
Activate the sleep timer function via the remote control. You can set the timer for durations between 30 and 180 minutes, after which the receiver will automatically power off.
6. Maintenance
To ensure the longevity and optimal performance of your KEiiD KD-240BT receiver, follow these maintenance guidelines:
- Cleaning: Use a soft, dry cloth to clean the exterior of the unit. Avoid using abrasive cleaners, solvents, or chemical sprays, as these can damage the finish.
- Ventilation: Ensure that the ventilation openings on the unit are not blocked. Proper airflow prevents overheating.
- Environment: Place the receiver in a dry, well-ventilated area away from direct sunlight, heat sources, and excessive dust or moisture.
- Power Off: Always power off and unplug the unit from the wall outlet before cleaning or when it will not be used for an extended period.
7. Troubleshooting
If you encounter issues with your KEiiD KD-240BT, please refer to the following common problems and solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| No power | Power cord not connected; Power outlet faulty; Unit is off. | Ensure power cord is securely plugged in. Try a different outlet. Press the POWER button. |
| No sound output | Incorrect input selected; Speaker cables loose; Volume too low; Mute function active. | Select the correct input source. Check all speaker connections. Increase MASTER volume. Ensure unit is not muted. |
| Bluetooth connection issues | Bluetooth antenna not connected; Device too far; Not in pairing mode; Interference. | Ensure Bluetooth antenna is attached. Move device closer to the receiver. Re-enter Bluetooth pairing mode. Avoid strong Wi-Fi signals or other wireless devices. |
| Remote control not working | Batteries depleted or incorrectly inserted; Obstruction between remote and receiver. | Replace batteries (2x AAA). Ensure correct polarity. Remove any obstructions. Point remote directly at the receiver's sensor. |
| Distorted sound | Volume too high; Speaker impedance mismatch; Poor audio source quality. | Reduce volume. Ensure speakers are 4-16 ohms (6-8 ohms recommended). Try a different audio source or cable. |
8. Specifications
Image: Overview of KEiiD KD-240BT dimensions, key features, and a detailed specifications table including media resources, rated power, sensitivity, THD, frequency response, S/N, Bluetooth version, and sleep timer range.
| Feature | Specification |
|---|---|
| Model | KD-240BT |
| Brand | KEiiD |
| Manufacturer | KEiiD Electronics |
| Output Power | 2 x 40W RMS (at 8 ohms) |
| Speaker Impedance | 4-16 ohms (6-8 ohms recommended) |
| Bluetooth Version | 5.0 |
| Wireless Range | Up to 65 feet (20 meters) in open areas |
| Audio Inputs | USB, Optical, SPDIF, RCA (AUX), 1/4" Microphone |
| Digital Input Support | Up to 16 bits/44.1 kHz |
| USB Media Format | WAV, FLAC, APE |
| Frequency Response | 20Hz-22kHz |
| Total Harmonic Distortion (THD) | <0.5% |
| Signal-to-Noise Ratio (S/N) | 80dB |
| Sleep Timer Range | 30-180 minutes |
| Power Source | AC100-240V |
| Dimensions (L x W x H) | 26 x 23 x 8 cm (10.2 x 9.2 x 3.1 inches) |
| Weight | 1.6 kg (3.9 lbs) |
| Compatible Devices | Speakers, Personal Computers, Televisions |
9. Warranty and Support
The KEiiD KD-240BT comes with a 1-year warranty. This warranty covers replacement in case of any failure or quality issues. For warranty claims or technical support, please contact your retailer or the KEiiD customer service department.
