Fosi Audio V3 Mono 

Next-Gen Monoblock Power Amplifier 

300W | Balanced Input | Ventilation

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Hear what they are saying

It is my pleasure to recommend Fosi Audio V3 Mono amplifier.

 

All l can say is wow! It is incredible how far these smallamplifiers have come, lt is the result of a manufacturer listening to our needs,implementing features such asbalanced and trigger inputs,and proper feedback mechanism to essentially eliminate load dependency.lcan't imagine asking for more from Fosi when it comes tosuch an amplifier. Everything is as good as you could possibly want, it is my pleasure to recommend Fosi AudioV3 Mono amplifier.

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Another Milestone Amp Crafted for Audiophiles

In 2023, following the launch of the V3 stereo amplifier, we received numerous valuable suggestions and feedback from our users. 

There are still points to be improved, such as the adoption of PFFB, but I expect further improvements in the future. --Toku from ASR 

It would be great if there was the PFFB, as Toku mentions, also no load dependency --ModDIY from ASR 

With balanced inputs and volume bypass ... this amp will be killer, even with a higher price tag (under 200 USD?) --mike70 from ASR 

I wish that they offered a mono block version (based on the V3). No volume pot. Simplified signal path. --markg4331 from Youtube 

I would have preferred a toggle on/off switch instead of the on/off switch being integrated on the volume pot. --cyclo from ASR 

We listen intently, record diligently, and develop with dedication, ultimately striving to transform your suggestions and ideas into reality—the V3 mono. 

PFFB Load Independence
Swappable Op-Amp Design
240W Rated Power Output
All-Aluminum Alloy Chassis
Full-Body Cooling Design
XLR Input
RCA Input
PFFB Load Independence
XLR Input
RCA Input
Swappable Op-Amp Design
Full-Body Cooling Design
All-Aluminum Alloy Chassis
240W Rated Power Output

PFFB Post-Filter Feedback Technology 

Significantly reduces distortion, enhances linearity and frequency response, and improves sound purity and system efficiency. 

Reproducing the Purest Sound 
Recreating Every Detail 

Effectively reduces the output impedance, thereby increasing the damping factor for tighter and more precise speaker response. 

Load Dependence Defeating 
Overcoming the Pain Point of Class-D Amps 

Reduces output filter impact, boosts frequency response for balanced, natural tones, ensuring true reproduction. 

240W Rated Power Output

Crafts an enriching, immersive sound experience, satisfying your craving for superior musical quality with unmatched audio richness.

Pure Sound, Accurate Imaging  
with Zero Crosstalk 

Enhances stereo depth and soundstage accuracy through precise power and channel separation 

for a purer audio experience. 

Compact and Exquisite 
With Minimalist Design

Effortlessly integrates into various settings like home theater, study room, desktop and studios without occupying too much space. 

All-Aluminum Alloy Chassis 
Sturdy and Durable 

Durably built from a single CNC-machined aluminum alloy piece, showcasing a robust and refined high-quality design. 

 

Premium Internal Components 

Carefully selected top-tier components are dedicated to crafting extraordinary sound quality, 

making every listening a pure delight. 

Japanese NICHICON 

63V/2200μF Filtering Capacitors 

Title

Eliminates the poor contact issues of traditional physical switches, ensuring stable and pure sound transmission.

German WIMA

Coupling Capacitors
 

Title

Provide exceptional sound quality and signal stability, greatly enhancing the audio experience.

Japanese Sumida

SMD Inductors

Title

Offer superior signal purity and noise reduction, elevating the amplifier's sound performance. 

ELNA, Japan

Audiophile-Grade Capacitors

Title

Ensure enhanced audio clarity and stability, contributing to a richer sound experience 

Japanese NICHICON 

63V/2200μF Filtering Capacitors 

Title

Eliminates the poor contact issues of traditional physical switches, ensuring stable and pure sound transmission.

German WIMA

Coupling Capacitors
 

Title

Provide exceptional sound quality and signal stability, greatly enhancing the audio experience.

Japanese Sumida

SMD Inductor
 

Title

Offer superior signal purity and noise reduction, elevating the amplifier's sound performance. 

ELNA, Japan

Audiophile-Grade Capacitors

Title

Ensure enhanced audio clarity and stability, contributing to a richer sound experience 

Flexibility

Adaptable to Various Scenarios

Offers enjoyment across various settings, from home theaters to professional studios, ensuring a versatile music experience. 

CONVENIENCE

Supports XLR Balanced and RCA Inputs 
Easily Switchable with a Toggle 

Provides you with flexible connectivity options that are easily adapted for both home and professional scenarios. 

XLR Balanced Input
Enhanced Interference Resistance

Ensures stable audio transmission for a precise, clear listening experience, fulfilling the quest for supreme sound quality. 

RCA Input
with 25dB and 31dB Gain Selection 

Enhances source adaptability and audio clarity, reducing distortion and overload risk, suitable for various audio setups.

FEATURES 

Swappable Op-Amp Design 

Easily replaceable DIP8 dual discrete op-amps, meeting your pursuit of a personalized audio experience. 

Four-Layer PCB Design 
All for Superior Sound Quality 

Boosts signal stability and audio purity, enhancing performance and interference resistance for superior sound output. 

 

Auto Standby Mode 
High Energy Efficiency 

Automatically enters standby after 10 minutes of no signal input, extending device lifespan and reducing power consumption. 

Advanced Cooling Design

Guarantees long-term efficient operation of the amp, prevents overheating, 

and maintains consistent sound quality and device longevity. 

Side Ventilation 
More Effective Cooling 

Boosts heat dissipation efficiency for superior performance and stable sound quality, ensuring enhanced air circulation. 

Dust-Proof Filter Screens 
Aesthetic and Practical 

Effectively blocks dust without compromising cooling, ensuring long-term stability and enhancing product durability. 

Optional 48V/10A Power Supply

Provides stable and robust power support, ensuring high-fidelity sound 

quality to meet diverse audio playback demands.

Powers Two V3 MONOs Simultaneously

With a power supply splitter cable, a single PSU can supply power to two amps, saving space and maintaining tidiness, offering you more flexible combination solutions. 

Measurements

Rated Power Output (1kHz, THD 1%)

Max Power Output (1kHz, THD 10%)

SINAD

SNR

Specifications

Channel: 1.0

Amplifier Chip: Texas Instruments TPA3255 

Input: RCA, XLR, ¼" TRS

Output: Speaker Output (supports banana plug or bare wire connection) 

SINAD: XLR: 101dB ; RCA: 93dB 

SNR: ≥123dB 

Dynamic Range: ≥123dB 

THD: ＜0.006% 

Gain: XLR/¼” TRS: 20dB ; RCA: 25dB, 31dB;  

Terminal Impedance: 2-8Ω 
Rated Power Output: 48V/5A--240W@4Ω ; 32V/5A --100W@4Ω 

Frequency Response: 10Hz-30kHz（±0.06dB）  

Input Voltage Range: DC 32-48V  

Standard PSU: 48V/5A 

Power Output with Various PSUs

PSU 

Load Impedance

Rated Power

(1kHz, THD 1%) 

Max Power

(1kHz, THD 10%) 

4Ω 

100W 

130W

32V/5A 

6Ω 

65W 

80W 

8Ω 

55W 

65W 

4Ω 

240W 

300W

48V/5A 

6Ω 

160W

200W

8Ω 

120W

150W