Introduction
Thank you for choosing the AIYIMA A70 Mono Amplifier. This high-performance audio device is designed to deliver exceptional sound quality for your home theater or music listening experience. Featuring the advanced TPA3255 D-Class amplifier chip and a PFFB (Post-Filter Feedback) circuit, the A70 Mono provides up to 300W of clean, powerful audio with minimal distortion. Its versatile connectivity options, including XLR and RCA inputs, along with a dedicated subwoofer output and 12V trigger, make it a flexible addition to any audio setup. This manual will guide you through the setup, operation, and maintenance of your new amplifier.
Safety Information
- Read all instructions carefully before operating the device.
- Do not expose the amplifier to rain, moisture, or extreme temperatures.
- Ensure proper ventilation around the unit to prevent overheating. Do not block ventilation openings.
- Use only the specified power supply (DC 24-48V).
- Do not open the casing. Refer all servicing to qualified personnel.
- Disconnect the power supply before making any connections or cleaning the unit.
Package Contents
Please check that all items are present in your package:
- AIYIMA A70 Mono Channel Amplifier x1
- User Manual x1
- Power Supply x1 (Optional, depending on purchase variant)
Product Overview
Familiarize yourself with the controls and connections of your A70 Mono Amplifier.
Front Panel
- OFF-ON/AUTO Switch: Toggles power or enables automatic power-on via 12V trigger.
- SW FREQ Knob: Adjusts the subwoofer cutoff frequency (40-200Hz) when in subwoofer mode.
- VOLUME Knob: Controls the overall output volume.
- XLR/RCA Input Switch: Selects between XLR and RCA audio input sources.
- Power Indicator: Illuminates when the unit is powered on.
- Input Mode Indicator: Shows the currently selected input (XLR or RCA).
Rear Panel
- XLR Input: Balanced audio input for professional audio sources.
- RCA Input: Unbalanced audio input for standard audio sources.
- RCA Gain Switch (16dB): Adjusts the gain for RCA inputs.
- SUB OUT: RCA output for connecting an active subwoofer.
- SUB FREQ: (Internal control, adjusted by front panel knob)
- 12V TRIGGER: Input/output for synchronized power control with other audio equipment.
- SPK OUT: Speaker terminals for connecting passive speakers.
- Power Input (DC24-48V): Connection for the external power supply.
Setup
Follow these steps to set up your AIYIMA A70 Mono Amplifier:
- Power Connection: Connect the DC 24-48V power adapter (if included or purchased separately) to the 'Power Input' port on the rear panel. Do not connect to a power outlet yet.
- Speaker Connection: Connect your passive speaker(s) to the 'SPK OUT' terminals on the rear panel. Ensure correct polarity (+ to + and - to -). The amplifier supports speaker impedances from 2-8Ω.
- Audio Source Connection:
- XLR Input: For balanced audio sources, connect an XLR cable from your source (e.g., DAC, preamplifier) to the 'XLR Input' port.
- RCA Input: For unbalanced audio sources, connect an RCA cable from your source to the 'RCA Input' ports. You can adjust the RCA gain using the 'RCA Gain Switch (16dB)' if needed.
- Subwoofer Connection (Optional):
- If using an active subwoofer, connect it to the 'SUB OUT' RCA port.
- If using a passive subwoofer, ensure the 'SUB/FULLRANGE' switch (located on the rear panel, near the speaker outputs) is set to 'SUB' mode. This allows the amplifier to act as a subwoofer amplifier, with the 'SW FREQ' knob controlling the cutoff frequency.
Figure 3: Output Mode Selection (Subwoofer vs. Full-range) - 12V Trigger Connection (Optional): If you have other audio equipment with a 12V trigger, connect it to the '12V TRIGGER' port for synchronized power control.
- Initial Power On: Once all connections are secure, plug the power adapter into a wall outlet. Set the 'VOLUME' knob to its minimum position before powering on.
Operating Instructions
Operating your A70 Mono Amplifier is straightforward:
- Power On/Off: Use the 'OFF-ON/AUTO' switch on the front panel. Set to 'ON' for manual power control. Set to 'AUTO' if using the 12V trigger for automatic power-on/off with other devices.
- Input Selection: Use the 'XLR/RCA' switch on the front panel to select your desired audio input. The 'Input Mode Indicator' will show the active input.
- Volume Control: Rotate the 'VOLUME' knob clockwise to increase the volume and counter-clockwise to decrease it. Adjust to a comfortable listening level.
- Subwoofer Frequency Adjustment: If the amplifier is configured for subwoofer output (via the rear panel switch), use the 'SW FREQ' knob on the front panel to adjust the bass cutoff frequency between 40Hz and 200Hz. This allows you to fine-tune the integration of your subwoofer with your main speakers.
- Output Mode: The switch on the rear panel (labeled 'SUB' and 'FULLRANGE' or similar) determines the amplifier's primary output function. Ensure it is set correctly for your speaker configuration (passive subwoofer or full-range speakers).
Specifications
Detailed technical specifications for the AIYIMA A70 Mono Amplifier:
| Parameter | Value |
|---|---|
| Chipset | TPA3255+NE5532 |
| Replaceable Op-Amp Chips | RT3609SM, OPA2604, OPA2134, LM4562, JRC5532, OP275GSZ, OPA1612, etc. |
| Distortion | 0.001% |
| XLR/RCA SNR | ≥ 116 dB |
| Frequency Response | 20Hz-20KHz (±0.5dB) |
| RCA Input Sensitivity (Low Gain) | 2Vrms (26 dB) |
| RCA Input Sensitivity (High Gain) | 1Vrms (32 dB) |
| XLR Input Sensitivity | 4Vrms (19 dB) |
| Speaker Impedance | 2-8Ω |
| Maximum Output Power (4Ω, 48V5A) | 300W |
| Input Mode | RCA+XLR |
| Supported Devices | Decoder, bilevel preamp, computer, CD, cell phone, MP3, etc. |
| SUB Output Sensitivity | 2V |
| Output Mode | 1.0 passive speaker / 0.1 subwoofer + active low-pass |
| Working Power Supply | DC 24-48V |
| Product Net Weight | 0.9 Kg |
| Package Size | 126.5 x 154.5 x 42mm |
Power Output Table
The table above provides detailed power output specifications under various conditions. Note that 'Max output power' refers to peak power, while 'Output Power' refers to RMS power.
Troubleshooting
If you encounter issues with your A70 Mono Amplifier, please consult the following common problems and solutions:
- No Sound Output:
- Check if the power indicator is on. If not, ensure the power adapter is securely connected and plugged into a working outlet.
- Verify that the 'OFF-ON/AUTO' switch is in the 'ON' or 'AUTO' position.
- Confirm that the correct input (XLR or RCA) is selected via the front panel switch.
- Ensure the volume knob is not at its minimum setting.
- Check all speaker and audio input cable connections for looseness or incorrect polarity.
- If using the 12V trigger, ensure the source device is powered on and sending the trigger signal.
- Distorted Sound:
- Reduce the volume level on both the amplifier and your audio source.
- Check if your speakers' impedance matches the amplifier's supported range (2-8Ω).
- Ensure the audio input cables are not damaged and are securely connected.
- If using RCA input, try adjusting the 'RCA Gain Switch (16dB)' on the rear panel.
- Verify that the power supply is stable and within the recommended voltage range (DC 24-48V).
- Amplifier Overheating:
- Ensure the amplifier has adequate ventilation. Do not place it in an enclosed space or cover its vents.
- Check if the speaker impedance is too low, causing the amplifier to work harder.
- Reduce the listening volume, especially during prolonged use at high power.
Figure 5: Heat Dissipation Design
User Tips
- Matching Speakers: For optimal performance and to prevent damage, ensure your speakers' impedance (2-8Ω) and power handling capabilities are compatible with the A70 Mono's output. Refer to the 'Power Output Table' in the Specifications section.
- Power Supply Quality: Using a high-quality, stable DC 24-48V power supply is crucial for achieving the best sound performance and maximum output power from your amplifier.
- Op-Amp Rolling: The NE5532 op-amp chips are replaceable. Experimenting with different compatible op-amps (e.g., RT3609SM, OPA2604, OPA2134) can subtly alter the sound signature to suit your preferences. Ensure the amplifier is powered off and unplugged before attempting to replace op-amps.
- PFFB Circuit Benefits: The integrated PFFB circuit significantly reduces distortion, resulting in a clearer and more authentic audio experience. This is especially noticeable with complex musical passages.
Maintenance
To ensure the longevity and optimal performance of your AIYIMA A70 Mono Amplifier, follow these maintenance guidelines:
- Cleaning: Use a soft, dry cloth to wipe the exterior of the amplifier. Do not use liquid cleaners or abrasive materials, as they may damage the finish.
- Ventilation: Always ensure that the ventilation holes on the sides of the amplifier are clear and unobstructed. Proper airflow is essential to prevent overheating, especially during extended use.
- Storage: When not in use for extended periods, store the amplifier in a cool, dry place away from direct sunlight and excessive dust.
- Avoid Liquids: Keep the amplifier away from water and other liquids to prevent electrical shock or damage to internal components.
Warranty and Support
AIYIMA products are manufactured to high-quality standards. For any warranty claims, technical support, or service inquiries, please contact your original point of purchase or the official AIYIMA customer support channels. Please retain your proof of purchase for warranty validation.
