AIYIMA A20 MONO

The AIYIMA A20 Mono is a compact, fully balanced Class D monoblock power amplifier designed around the Texas Instruments TPA3255 chipset and Post-Filter Feedback (PFFB) technology. Each unit powers a single passive speaker, meaning you need two units for a stereo setup.

Features:

1. Advanced PFFB Technology for Consistent Sound Quality:

Equipped with the latest PFFB (Post Filter Feedback) design, the A20 MONO significantly reduces load-dependent distortion and frequency response variations, delivering accurate and stable sound performance with different speaker loads.

 

2. Powerful TPA3255 Mono Amplifier:

Featuring the renowned TPA3255 Class D amplifier chip, the A20 MONO delivers up to 620W @ 2Ω, 300W @ 4Ω, and 170W @ 8Ω, providing ample power for bookshelf, floor-standing, and high-performance speakers.

 

3. Audiophile-Grade Components:

Built with premium OPA1612, replaceable LME49720 op-amp, WIMA capacitors, and Rubycon 63V 3300μF capacitors, ensuring exceptional clarity, dynamics, and musical detail.

 

4. Balanced & Versatile Connectivity:

Supports XLR, RCA, and TRS inputs, making it easy to connect DACs, preamps, mixers, PCs, CD players, and professional audio equipment for both home and studio applications

 

Key Specifications & Hardware

• Amplification & PFFB. Uses a TI TPA3255 chip paired with a PFFB loop to lower output impedance and maintain consistent frequency response across different speaker loads.
• Clean Power Output. Delivers 200W into 4Ω and 100W into 8Ω at 1% THD. Peak advertised figures reach up to 300W into 4Ω at higher distortion levels.
• Audio Performance. Rated with a signal-to-noise ratio over 118 dB and 0.002% THD+N. [1]
• Internal Components. Built with two 63V/65V 3300µF Rubycon capacitors and a single user-swappable op-amp inside a ventilated aluminum chassis.
• Front VU Meter. Features a working vintage-style mechanical VU meter on the front panel alongside a physical input/off switch.

Product Specification:

Amplifier Chip: TPA3255

OP AMP Chip: OPA1612 (Non-Replaceable) + LME49720 (1 Replaceable)

Key Components: WIMA Capacitors + Rubycon 63V 3300μF Capacitors

Maximum Output Power:
300W @ 4Ω THD+N < 10%
170W @ 8Ω THD+N < 10%
620W @ 2Ω THD+N < 10%

Rated Output Power:
200W @ 4Ω THD+N < 1%
100W @ 8Ω THD+N < 1%
400W @ 2Ω THD+N < 1%

SNR: ≥118dB

THD+N: 0.002%

Frequency Response: 20Hz-20kHz (+0.4dB)

Input Interfaces: RCA, XLR, TRS

Output Interfaces: Passive Speaker Output + Active Subwoofer Output

Supported Devices: DAC, Preamplifier, PC, CD Player and More

SUB Output Level: 2V

SUB Output Frequency: 20Hz-200Hz (Can Follow HPF Cutoff to 80Hz)

High-Pass Filter Frequency: 80Hz

High-Pass Filter Slope: 12dB

RCA Gain: 19dB / 25dB

XLR Gain: 20dB

Speaker Impedance: 2-8Ω

Power Supply: DC 32-48V

Product size: 80 × 140 × 90mm

Package size: 207 × 198 × 124mm

Net Weight: 950g

Package Weight: 1490g

Connectivity & Controls

• No Volume Control. Because it is a dedicated power amplifier, it lacks a volume knob and requires a preamplifier, DAC with volume control, or AV receiver.
• Inputs & Outputs. Supports both balanced XLR and single-ended RCA inputs, heavy-duty speaker terminals, and a dedicated subwoofer output.
• Bass Management. Includes a rear toggle switch for a fixed 80 Hz high-pass filter to relieve smaller main speakers when paired with a subwoofer.
• Gain & Power Sync. Offers a two-stage gain switch (19 dB or 25 dB) to match different source outputs, a 12V trigger input for automatic power-on, and a 20-minute auto-standby mode.

Reviewer Impressions & Comparisons

• Sound Profile. Reviewers on YouTube note punchy, warm bass and solid detail retrieval for its price bracket. Another comparison on YouTube describes its tuning as slightly V-shaped and energetic compared to the Fosi Audio V3 Mono, with a larger chassis for better heat dissipation.

FAQ

Q: Do I need two A20 MONO amplifiers for stereo sound?

A: Yes. One A20 MONO drives one speaker channel. For stereo playback, two units are required—one for the left speaker and one for the right speaker.

 

Q: Will the A20 MONO sound harsh like typical Class D amplifiers?

A: No. With advanced PFFB technology, the A20 MONO delivers a smoother, more natural sound while maintaining the clarity and efficiency of a Class D amplifier.

 

Q: Which gain setting should I choose, 19dB or 25dB?

A:

19dB: Best for high-output sources such as balanced XLR DACs or preamps.

25dB: Best for lower-output sources such as RCA devices, providing higher sensitivity and output level.

 

Q: Does the amplifier get hot? Is it safe for long-term use?

A: The A20 MONO uses a highly efficient Class D design with an aluminum alloy chassis for heat dissipation. It remains warm during operation and is suitable for extended listening sessions.

 

Q: What cable is required for the 12V Trigger input?

A: Use a standard 3.5mm trigger cable. The 12V Trigger input allows synchronized power on/off with compatible audio equipment.

 

Q: How does the 20-minute auto standby function work?

A: If no audio signal is detected for 20 minutes, the amplifier automatically enters standby mode. Playback will automatically resume when an audio signal is detected.

 

Q: Does the VU meter stay illuminated in standby mode?

A: YES.

 

Q: Will there be a "pop" sound from the speakers when powering on or off?

A: No. The A20 MONO features a built-in soft-start protection circuit to prevent power-on and power-off noise, helping protect your speakers and drivers.

 

Q: The VU meter needle barely moves. Is it defective?

A: No. The VU meter responds to output power. At low volume levels or with less dynamic music, needle movement may be minimal. Increasing the volume or playing more dynamic content will result in more noticeable movement.

 

Q: How should I match the input sensitivity with my preamp?

A: The input sensitivity is 2.0V for RCA and 4.0V for XLR, matching most DACs and preamplifiers. For high-output sources, use the 19dB gain setting to avoid input overload.

 

Q: Why do my bookshelf speakers sound thinner when HPF is enabled?

A: This is normal. Enabling HPF filters out frequencies below 80Hz. For full-range sound, connect an active subwoofer to the SUB OUT output.

 

Q: Can I build a 5.1 or 7.1 system with A20 MONO amplifiers?

A: Yes. Multiple A20 MONO amplifiers can be used to build multi-channel systems, providing dedicated power for each speaker channel.

 

Q: Why does the SUB OUT frequency change when HPF is enabled?

A: When HPF is enabled, the SUB OUT crossover frequency automatically follows the 80Hz HPF setting to ensure smooth integration between the speakers and subwoofer. This helps achieve a more balanced 2.1 audio system.