Engineered for Audiophiles - Optimal Choice for Home Audio Systems

In 2023, following the launch of the V3 stereo amplifier, we received numerous valuable suggestions and feedback from our global audio lovers. We listen intently, record diligently, and develop with dedication, ultimately striving to transform your suggestions and ideas into reality—the V3 mono.

  • Input: RCA, XLR, ¼" TRS; Output: Passive Speaker (supports banana plug or bare wire connection)
  • SINAD: XLR--101dB; RCA--93dB; SNR: ≥123dB
  • Rated Power Output: 48V/5A 240W@4Ω; 32V/5A 100W@4Ω

NICHICON Caps, Japanese

Ensure superior sound clarity, longevity, and stable electrical performance, enhancing the fidelity of audio reproduction.

WIMA Caps, German

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

Sumida Inductor, Japanese

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

ELNA Caps, Japan

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

Product details

Description
  • Mini Monoblock Amplifier: Crafted for HiFi audiophiles, the V3 Mono allows you to drive a single passive speaker with one amp, delivering up to 240W @4Ω of rated power. It offers the flexibility to build your home audio 2/3/4/5-channel system effortlessly. The V3 Mono can serve as a power amplifier for multi-channel AVRs, complementing the output power to easily drive high-power speakers in home theater systems.

  • Innovative Cutting-Edge Technology: Fosi Audio has achieved a technological breakthrough through independent research and development by applying PFFB (Post-Filter Feedback) technology to the V3 Mono for the first time. This effectively overcomes the common load dependency issues of Class-D amplifiers, improving distortion and enhancing frequency response, thereby significantly enhancing sound quality and performance.

  • Audiophile-Grade Components: The V3 Mono incorporates the high-end TPA3255 Class-D amp chip, paired with well-known components such as Japanese Nichicon filter capacitors, ELNA capacitors, German WIMA capacitors, and Japanese Sumida inductors, etc. Additionally, it features an upgraded four-layer PCB. This combination not only ensures high power output but also achieves a THD as low as 0.006%, a SINAD of 101dB, and an SNR of 123dB. As a result, the fidelity and quality of the audio are assured.

  • Advanced Cooling: Utilizing Fosi Audio's pioneering full-body heat dissipation design, the TPA3255 amplifier chip is placed at the bottom and tightly integrated with the chassis, allowing heat to be effectively dissipated through the casing. Coupled with dual side ventilation holes that enhance internal airflow, this ensures the V3 Mono can deliver stable, high-power output over extended periods.

  • User-Friendly Design: Supports both XLR/¼" TRS balanced and RCA single-ended(with gain selection) inputs, with an easy toggle switch for selection. Additionally, it features an auto power/signal sensing mode to enhance energy efficiency. You can also customize your preferred sound signature by replacing the stock NE5532 op-amps, supporting DIP8 dual discrete op-amps such as Sparkos SS3602, MUSES02, OPA2604, Burson V5i, V6, V7, and more.

  • V3 mono stereo audio component mini power monoblock amplifier 2 channel amplifier single channel 2/2.1/3/4/5 channel class d amp tpa3255 for home theater desktop outdoor bookshelf Tower floorstanding passive speakers ZA3.
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 
What‘s in the box?

Which Product is right for you?

Compare products to find the best one for your needs.

Fosi Audio V3 Mono Power Amplifier for Home Audio Speakers, Mini Monoblock Class D Amp - Fosi Audio

Fosi Audio V3 Mono Monoblock Power Amplifier

Type
Monoblock
Amp Chip
TPA3255
MAX Power Output
300W@4Ω
Input
RCA, XLR, ¼”TRS
Output
Speaker Output
Treble & Bass Control
No
THD+N
<0.006%
SNR
≥123dB
Terminating Impedance
2-8Ω
Power Supply
32V/5A, 48V/5A
Fosi Audio ZA3 Balanced Stereo Amplifier Home Audio - Fosi Audio

Fosi Audio ZA3 Balanced Stereo Amplifier

Type
2.0 CH Amp
Amp Chip
TPA3255
MAX Power Output
2x 300W@4Ω
Input
RCA, XLR, ¼”TRS
Output
Speaker Output, Sub-Out
Treble & Bass Control
No
THD+N
<0.006%
SNR
≥106dB
Terminating Impedance
2-8Ω
Power Supply
32V/5A, 48V/5A
Fosi Audio V3 300W x2 2.0 Channel Hi - Fi Stereo Audio Amplifier with TPA3255 Chip - Fosi Audio

Fosi Audio V3 Mini Stereo Amplifier

Type
2.0 CH Amp
Amp Chip
TPA3255
MAX Power Output
2x 300W@4Ω
Input
RCA
Output
Passive Speakers, Pre-Out
Treble & Bass Control
No
THD+N
<0.003%
SNR
≥110dB
Terminating Impedance
2-8Ω
Power Supply
32V/5A, 48V/5A
Fosi Audio BT20A PRO 300W x2 TPA3255 2 Channel Bluetooth 5.0 Power Amplifier - Fosi Audio

Fosi Audio BT20A Pro Bluetooth Stereo Power Amp

Type
Bluetooth 2.0 Ch Amp
Amp Chip
TPA3255
MAX Power Output
2x 300W@4Ω
Input
Bluetooth, RCA
Output
Speaker Output, Pre-Out
Treble & Bass Control
Yes
THD+N
≤ 0.005%
SNR
≥ 108dB
Terminating Impedance
2-8Ω
Power Supply
32V/5A, 48V/5A
Fosi Audio M03 Subwoofer Amplifier

Fosi Audio M03 Subwoofer Mono Amplifier

Type
Subwoofer Amp/MoxAmp
Amp Chip
MAX Power Output
200W
Input
RCA
Output
Passive Speakers + Active/Passive Subwoofer
Treble & Bass Control
No
THD+N
≤0.03%
SNR
≥ 106dB
Terminating Impedance
4-8Ω
Power Supply
32V/5A

FAQs

Please read our FAQs page to find out more.

The V3 Mono has three op-amps. What does each one do? And if l want to get a better sound, which one should l change?

The three op-amps in the V3 Mono serve distinct functions: Position 1 converts the RCA unbalanced signal to a balanced signal, while positions 2 and 3 adjust the tone. lf you're considering replacing an op-amp, it's recommended to start with the one in position 2. Replacing both the op-amps in positions 2 and 3 will have a more noticeable effect. Users can try swapping different op-amps to experience changes in sound quality.

For the V3 Mono do I need any specific type of op-amp?

It supports DIP8 dual op-amps. We highly recommend the op-amp available through the following link: https://fosiaudio.com/products/op-amp-chip-muses02-opa2604ap-opa2134pa?_pos=20&_sid=71ca24042&_ss=r
Using different op-amps can result in various sound signatures. Please refer to the video via the link: https://youtu.be/jtK9oYZ_XoI

The V3 MONO's power LED does not work but it outputs sound.

Check if the LED is out of position after swapping the op-amp. Open the unit and align the LED correctly.

Customer Reviews

Based on 119 reviews
74%
(88)
13%
(16)
7%
(8)
1%
(1)
5%
(6)
O
Outof Into
These Fosi v3 monoblocks are exceptional

I bought 4 of these Fosi v3 monoblocks with 2 x 48volt/10amp power supply units. They are being used to drive Tannoy XT8F revolution tower speakers in a vertical mono/bi-amp mode ( i.e. each speaker is connected to 2 monoblocks with a shared PSU ).
After an initial 24 hour burn in, they opened up to produce a wonderfully transparent, dynamic and powerful sound. The treble is clean without edge or grain, the midrange is very clear with excellent low level detail resolution and the bass is well controlled, defined, extended and surprisingly hard hitting. The overall tonal balance is quite neutral with just a hint of treble forwardness.
The Fosi v3 small form factor, belies its capability when producing a very large soundstage with terrific focus on, and the space between, the musical elements within it. Plus the stereo imagery is precise with good centre focus, coherence and decent depth.
I was originally sceptical about the V3 mnbks when I heard, read and saw ( on You tube ) the rave reviews about them. Now I have confirmed for myself, their exceptional performance for the money.
Compared to my 2 other, much more expensive power amps, from Marantz and Emotiva, they more than hold their own.
Highly recommended.
Additional information:- Everything said about the v3 monoblocks remains the same, ( if anything they're even better sounding than when they were first reviewed, due to slightly less treble forwardness ). However they do become hot during use.
Therefore I recommend using a low noise fan ( if you can't put them on/in a well ventilated shelf/cabinet ). DON'T stack them on top of each other without adding feet to separate them.

A
Alex
Amazing amp at an even better price

These amps are excellent, and an amazing value. Can even be upgraded with different OPamps. great design! Currently using 7 of these for my home theater setup

D
Donnie L
V3 monos

These mini monos easily power my KEF LS50 Metas (Wiim Ultra, Hisense Canvas monitor) to fill the workout studio with wonderful sound! Upgraded with SparkoS Labs SS3602 op-amps.

Every room deserves a Fosi! (Garage too)

m
miha
Decent product

Nice if separte PSUs

S
S R
Powerful

Powerful compared to its size.