SPECIFICATIONS

AIYIMA Model: AIYIMA A20

Brand Name: Aiyima

Certification: CE,KC

Channels: 2 (2.0)

Control Method: Push button

High-concerned chemical: none

Material: Metal

Maximum Power Per Channel: Above 200W

Model Number: A20

Origin: Mainland China

Output Power: 300W*2

Package: Yes

Surround sound channel configuration: Others

function: BYPASS

Features:

1、High-end components: The A20 amplifier uses the TPA3255 Class D amplifier chip and is equipped with German WIMA, Japanese Genicon, Ruby capacitors and gold-plated terminals. achieving a signal-to-noise ratio (SNR) of up to 116dB and a distortion rate as low as 0.002%

2、HPF High Pass Filter Adjustment: The TPA3255 desktop amplifier features an adjustable high pass filter (HPF) with an adjustable range of 60-200Hz. It optimises mid and high frequencies for clear and transparent mid and high tones while minimising low frequency interference.

3、Rich connectivity options: with RCA/XLR input interfaces and a 12V trigger.

3.1、Balanced inputs effectively reduce noise, providing pure stereo output, and restore true sound quality through independent low-frequency drivers.

3.2、The 12V trigger input interface enables synchronised control with other devices, simplifying the power switch operation process without the need for separate operations.

4、Enhanced sound quality: The A20 Class D amplifier uses two LME49720 (plug-in) and seven NE5532 (surface-mount) operational amplifier chips to achieve ultra-low distortion, low noise, and extremely transparent sound quality without colouration.

5、BYPASS Function: The A20 Integrated Amplifier features a bypass mode, which reduces audio quality loss, making it a high-fidelity pure power amplifier.

Note: In bypass mode, the amplifier volume is set to maximum. Before switching to bypass mode, please lower the volume at the source end to avoid hearing damage and speaker damage. This mode has a memory function; to exit, press and hold for three seconds.

6、PFFB circuit design: A20 uses PFFB (post-filter feedback) technology to effectively overcome the common load dependence problem of Class D amplifiers, improve distortion, enhance frequency response, and thus greatly improve sound quality and performance.

T20 Vacuum Tube Preamplifier:https://www.aliexpress.com/item/1005009412545246.html

Product Specification:

Power amplifier chip: TPA3255

OP amp chip: LME49720*2 (plug-in), NE5532*7 (surface-mount)

Replaceable OP amp chips: LM4562, NE5532, OPA2604, OPA2134, JRC5532, Muse02, etc.

Other key components: WIMA capacitor/Ruby capacitor/Japan NJW1195 volume IC

Input interface: RCA, XLR

Output interface: SPEAK OUT, SUB OUT

Other interfaces: 12V trigger input

Signal-to-noise ratio (SINAD): ≥95dB

Signal-to-noise ratio (SNR): ≥116dB

Dynamic range: ≥110dB

Distortion (THD+N): 0.002%

Speaker impedance: 4-8Ω

Input sensitivity: RCA: 2V XLR: 4V

SUB output level: 2V

SUB output frequency range: 20-200Hz

Frequency response: 20Hz-20kHz (±0.4dB)

Output power: 300W*2 (4Ω)

Other Features: BYPASS Volume Bypass/RCA Gain (3dB)/HPF High-Pass Filter (60-200Hz)

Supported devices: mobile phones, tablets, computers, decoders, preamps, streaming media, CD players, etc.

Output mode: 1.Passive speaker 2.Passive speaker + active subwoofer

Working power supply: DC 24-48V

Product size: 190*142*46mm

Packing size: 296*228*77mmmm

Product net weight: 1115g

Packing weight: 1240g (without power supply)

A20 Design Concept Q&A

Q: What is HPF and what does it do?

A: HPF stands for High-Pass Filter. As the name suggests, it allows high-frequency signals to pass through while blocking (or attenuating) low-frequency signals. Its main functions are:

1.Protecting main speakers: Prevents ultra-low frequencies from passing through, ensuring the speakers operate safely within their linear frequency range.

2.Improving overall sound quality and clarity: Reduces distortion, enhances mid-bass definition, and increases power headroom (this is particularly important, as it allows the amplifier’s power to be more efficiently allocated to mid and high frequencies, resulting in louder output and greater dynamics).

3.Enabling crossover with subwoofers: The main speakers handle mid/high frequencies while the subwoofer covers the low frequencies, achieving higher efficiency, lower distortion, and more impactful sound—forming a complete 2.1 audio system.

Q: Why are the values 60/80/120/200Hz marked?

A: These are standard crossover points commonly used in the industry, designed for the following purposes:

1.Matching speaker characteristics:

a.Small satellite/micro speakers: Their bass response often rolls off sharply around 150Hz. Setting HPF at 120Hz or 200Hz helps protect them and compensates for their weak low-end.

b.Medium bookshelf/small floorstanders: Typically perform well down to 60–80Hz. Setting HPF at 60Hz or 80Hz removes sub-bass they struggle with, while making full use of their natural bass capability.

c.Large floorstanders: If they extend well into the sub-bass (down to 40Hz or lower), HPF can be set to “Full Range/Bypass” or at a very low point (e.g., 40Hz) purely as protection.

2.Aligning with human hearing and acoustics:

Below ~80Hz, human ears struggle to localize the direction of sound. Above 80Hz, localization becomes noticeable—if a fixed-position subwoofer handles higher frequencies, it can break soundstage coherence. That’s why 80Hz is often considered the best balance point between powerful bass and seamless imaging.

3.Providing tuning flexibility:

Offering a range of crossover points (60–200Hz) gives users the freedom to fine-tune according to their specific speakers, room acoustics, and personal listening preferences.（Tip: Starting at 80Hz is the safest and most balanced choice. Users can then fine-tune slightly up or down based on their system and room response.）

Q: What is BYPASS? Why is this feature included, and in what scenarios is it used?

A: The BYPASS function allows the amplifier to bypass its internal tone controls (Bass/Treble), equalizer (EQ), sound field processing (such as DSP modes), and—most importantly—the preamplifier stage. In this mode, the input signal is delivered to the power amplification stage in the most direct and unaltered way, typically at a fixed (maximum) volume level.

This feature is included for the following purposes and use cases:

1.Pursuing ultimate sound quality: Reduces signal loss and distortion, preserving the absolute integrity of the source audio.

2.Using the amplifier as a pure power amp: Enables seamless integration with an independent external preamplifier.

3.Integration into more complex home theater systems: With active subwoofer output, BYPASS mode allows the amplifier to function as part of a complete 2.1 home theater setup.

Package Include:

• A20 Amplifier x1

• 12V trigger cable x1

• Warranty Card x1

• User Manual x1

• • 48V 5A power supply (option required)*1