1. Introduction
The SMSL A300 is a high-performance Class D integrated amplifier designed for audiophiles. It features Bluetooth 5.0 connectivity, multiple input options, and the ability to configure a 2.1 audio system. This manual provides detailed instructions for setting up, operating, and maintaining your A300 amplifier to ensure optimal performance and longevity.
2. Safety Information
- Do not expose this unit to rain or moisture.
- Do not disassemble the unit. Refer all servicing to qualified personnel.
- Ensure proper ventilation around the unit to prevent overheating.
- Use only the specified power adapter and cables.
- Keep the unit away from heat sources, direct sunlight, and strong magnetic fields.
3. Product Overview
Front and Rear Panel Layout
Figure 3.1: SMSL A300 Front and Rear Panel with labeled components.
The diagram above illustrates the various components and connections on the front and rear panels of the SMSL A300 amplifier. Each numbered item corresponds to the description below:
- Display Screen: Shows current volume, input, and menu settings.
- Remote Window: Infrared receiver for the remote control.
- Knob: Multi-function control for volume adjustment and menu navigation.
- Input Button: Selects the audio input source.
- Menu Button: Accesses the amplifier's settings menu.
- On/Off Button: Powers the unit on or off.
- Analog Input 2: RCA input for external audio devices.
- Analog Input 1: RCA input for external audio devices.
- Right Channel Output (BTL): Speaker output for BTL (Bridge-Tied Load) mode.
- Connect to Computer (USB): USB input for connecting to a computer (supports up to 45kHz).
- Bluetooth Antenna: For wireless Bluetooth reception.
- Right Channel Output: Standard speaker output for the right channel.
- Left Channel Output: Standard speaker output for the left channel.
- Power Input: Connects to the AC power cable.
- Subwoofer Output: Pre-output for connecting an active subwoofer.
4. Features
- Advanced Volume Control: Utilizes the Japanese NJRC NJW1194 electronic volume control chip for precise volume adjustment and minimal distortion.
- BTL (Bridge-Tied Load) Technology: Enhances power output and efficiency, allowing for up to 165W per channel into a 4Ω load in mono amplified mode.
- High-Performance Amplifier Chip: Incorporates the German Infineon MA5332MS digital high-power amplifier chip for high efficiency and low energy consumption.
- Versatile Input Options: Supports RCA, USB, and Bluetooth 5.0 inputs for broad compatibility with various audio sources.
- 2.1 Audio System Capability: Features a dedicated subwoofer signal pre-output and a built-in high-pass filter circuit, enabling easy connection of an active subwoofer to form a 2.1 system.
- Sound Customization: Offers 8 preset EQ options and adjustable treble/bass controls to fine-tune the sound to your preference and speaker characteristics. Includes SMSL SDB patented sound effects.
- Robust Construction: Crafted from aluminum alloy with precision CNC-processing, anodizing technology, and chamfering for a durable and refined finish.
- User-Friendly Operation: Intuitive operating system with a full-featured remote control for convenient use.
5. Setup
5.1 Connecting Speakers
The A300 amplifier supports both normal stereo mode and BTL (Bridge-Tied Load) mono mode for increased power output to a single speaker.
Figure 5.1: Normal Mode vs. BTL Mode Speaker Connections.
- Normal Mode (Stereo): Connect your left speaker to the 'Left' output terminals and your right speaker to the 'Right' output terminals on the rear panel. Ensure correct polarity (+ to + and - to -).
- BTL Mode (Mono): For higher power to a single speaker, connect the speaker to the dedicated 'Right Channel Output during BTL' terminals. Refer to the amplifier's menu to activate BTL mode (display will show 'br1' for mono, 'br0' for stereo).
5.2 Connecting a 2.1 Audio System
To enhance bass performance, you can connect an active subwoofer to the A300 amplifier to create a 2.1 audio system.
Figure 5.2: 2.1 Audio System Connection.
- Connect your passive speakers to the 'Left' and 'Right' channel outputs as described in Normal Mode.
- Connect the 'Subwoofer Output' (15) on the rear panel of the A300 to the input of your active subwoofer.
- The A300 features a built-in high-pass filter to optimize sound distribution between your main speakers and the subwoofer.
5.3 Input Connections
- RCA Inputs (Analog 1 & 2): Connect analog audio sources (e.g., CD player, turntable with pre-amp) to the 'Analog Input 1' (8) or 'Analog Input 2' (7) using RCA cables.
- USB Input: Connect a computer to the 'Connect to Computer (USB)' (10) port using a USB cable. This input supports audio up to 45kHz.
- Bluetooth: Ensure the Bluetooth antenna (11) is securely attached. For pairing, refer to the 'Operation' section.
6. Operation
6.1 Basic Controls
- Power On/Off: Press the 'On/Off button' (6) on the front panel.
- Volume Adjustment: Rotate the 'Knob' (3) to adjust the volume level.
- Input Selection: Press the 'Input button' (4) to cycle through available input sources (RCA 1, RCA 2, USB, Bluetooth).
- Menu Navigation: Press the 'Menu button' (5) to enter the settings menu. Use the 'Knob' (3) to navigate and select options.
6.2 Remote Control
The A300 comes with a full-featured remote control for convenient operation from a distance. Point the remote towards the 'Remote Window' (2) on the front panel. The effective distance is typically 0-10 meters.
6.3 Bluetooth Pairing
Figure 6.1: Bluetooth 5.0 Connectivity.
- Select Bluetooth as the input source using the 'Input button' (4) or the remote control.
- On your Bluetooth device (smartphone, tablet, etc.), search for available Bluetooth devices.
- Select "SMSL A300" from the list to pair. Once paired, the display will indicate a successful connection.
6.4 Sound Settings
- EQ Presets: Access the menu to select from 8 preset EQ options to tailor the sound profile.
- Treble/Bass Adjustment: Within the menu, you can manually adjust treble and bass levels to suit your listening preferences and speaker characteristics.
6.5 Display Settings
The display brightness can be adjusted through the menu settings to match your environment.
7. Specifications
| Specification | Value |
|---|---|
| Brand | S.M.S.L |
| Model Number | A300 |
| Output Power (4Ω) | 165W x 2 (Stereo), 330W x 1 (BTL) |
| Output Power (8Ω) | 85W x 2 (Stereo) |
| Number of Channels | 2 |
| THD+N | 0.004% |
| Inputs | RCA (x2), USB, Bluetooth 5.0 |
| Outputs | Speaker Terminals, Subwoofer Pre-out |
| Item Dimensions (L x W x H) | 8.26 x 7.8 x 1.6 inches |
| Item Weight | 2.86 pounds |
| Voltage | 220 Volts (AC) |
| Manufacturer | S.M.S.L |
8. Troubleshooting
- No Sound:
- Check all cable connections (power, input, speaker).
- Ensure the correct input source is selected.
- Verify speaker connections and polarity.
- Check the volume level on both the amplifier and the source device.
- If in BTL mode, ensure the speaker is connected to the correct BTL output.
- Bluetooth Not Connecting:
- Ensure Bluetooth input is selected on the A300.
- Make sure the Bluetooth antenna is securely attached.
- Delete "SMSL A300" from your device's Bluetooth list and try pairing again.
- Move your device closer to the amplifier.
- Distorted Sound:
- Reduce the volume level.
- Check for loose cable connections.
- Ensure your speakers are compatible with the amplifier's power output.
- Remote Control Not Working:
- Check the battery in the remote control.
- Ensure there are no obstructions between the remote and the amplifier's remote window.
- Point the remote directly at the remote window.
9. Maintenance
- Cleaning: Use a soft, dry cloth to clean the exterior of the unit. Do not use liquid cleaners or aerosols.
- Ventilation: Ensure the ventilation openings are clear and not obstructed by dust or other objects.
- Storage: If storing the unit for an extended period, disconnect it from the power supply and store it in a cool, dry place.
10. Warranty and Support
S.M.S.L is committed to providing excellent products and services. All S.M.S.L products purchased from authorized retailers are 100% authentic.
- Warranty Period: Products typically come with a 1-year warranty from the date of purchase (may vary depending on product and region).
- Customer Support: For any questions or assistance, please contact the seller or S.M.S.L customer service. Online support is available.
