The V3 Mono is a mono power amplifier by Fosi Audio that delivers 240 watts into 4 ohms with the 48V/5A supply, or 100 watts with the 32V/5A one, per chassis. This is a monoblock: a stereo system needs two. Fosi publishes no 8 ohm rating. It was released in 2024. It is a 1-channel design using a Class D output stage. Speakers connect via binding posts. A minimum impedance of 2 ohms makes it compatible with a wide range of loudspeakers. The Fosi Audio V3 Mono has an MSRP of $110.
There are 3 Fosi Audio amplifiers in our database. Below you can see the main specs of these amps.
Fosi Audio Power Amplifier Series
Performance Specs
One of the most important factors when deciding on an integrated amplifier is its power ratings and compatibility with your speaker's impedance requirements. The Fosi Audio V3 Mono is rated at 240 watts RMS into 4-ohms. Fosi Audio provides this wattage at a THD (Total Harmonic Distortion) of 0.006% which is an important indicator of distortion at the given values (lower THD is better).
Here are the main highlights of its performance specs:
Wiring more than one pair of speakers to it? Check the load first →
When pairing the Fosi Audio V3 Mono with a passive Bookshelf (Stand mount) or Passive Floor Standing (Tower) speaker, you have to check if their Max Power Range is below the max wattage of the amp for the given impedance levels.
Operating your amp outside of this max range may damage the speakers.
Inputs and Outputs
Besides the performance specs of the Fosi Audio V3 Mono, the next important feature set that you have to evaluate is the input and output selections that it offers.
Fosi Audio V3 Mono has total of 2 Analog inputs .
Inputs
- Total Number of Analog Inputs: 2
Outputs
Bluetooth Connectivity
Fosi Audio V3 Mono doesn't have bluetooth connectivity feature. In order to stream your music via bluetooth, the easiest way is to connect an external bluetooth receiver to your Fosi Audio V3 Mono. Two bluetooth receivers that we recommend are the
iFi Zen Blue V2 and the
Audioengine B1.
Among the amps in the same price range, these are the 5 amps that have Bluetooth Connectivity:
Phono Input
Fosi Audio V3 Mono doesn't have a phono input so in order to play your vinyl albums, Fosi Audio V3 Mono has to be paired with a Phono Preamp that is MM (Moving Magnet) or/and MC (Moving COil) depending on your cartridge type.
Balanced connections
Fosi Audio V3 Mono has a balanced XLR input. A balanced cable carries the signal twice, on two conductors of opposite polarity. Interference picked up along the way lands on both equally and cancels when the two are recombined at the far end, so the longer the cable run and the noisier the surroundings, the more the connection is worth. Whether a balanced connection also yields more power depends on how the amplifier is built inside - some are balanced end to end, others convert to single-ended internally and deliver the same power either way, so it is worth reading the maker's own wording rather than assuming.
Fosi Audio V3 Mono Pros and Cons
Drawn from the published figures on this page, not from listening.
- ✓Rated down to 2 ohms, so even a speaker with a punishing impedance dip is within its brief.
- ✓Class D output stage, so it runs cool and wastes little power as heat - which is how it fits in a small case.
- ✓Distortion is specified at 0.006%, an order of magnitude below what is generally held to be audible.
- ✓A monoblock - one per speaker, so the two channels share no power supply and no chassis.
- ✓Balanced XLR inputs, worth having on a long cable run.
- ✗Being a monoblock, you need two of them for stereo.
- ✗A power amplifier has no volume control and no input selection - it needs a preamplifier, or a source with a variable output, in front of it.
Fosi Audio V3 Mono External Dimensions and Weight
Fosi Audio V3 Mono has external dimensions of (H x W x D) .
- Width: mm (")
- Height: mm (")
- Depth: mm (")
- Weight: —
- Base Surface Area: ~cm2 / 0.0inch2
- Volume: ~0.0 liter / 0.0 gallon
Available colors
Fosi Audio V3 Mono is available in Black color options.
| General |
| Brand |
Fosi Audio |
| Full Model Name |
Fosi Audio V3 Mono |
| Release Date |
2024 |
| Amplifier Type |
Power Amplifier |
| Number of Channels |
1 |
| Amp Class |
Class D |
| Amplifier Technology |
Solid State |
| Performance |
| Watts RMS per Channel into 8-ohms |
N/A |
| Watts RMS per Channel into 6-ohms |
N/A |
| Watts RMS per Channel into 4-ohms |
240 watts |
| Frequency Bandwidth |
10 Hz-30 kHz |
| THD |
0.006% |
| Minimum Impedance |
2 |
| Signal to Noise Ratio |
N/A |
| Digital Music |
| Built-in DAC |
No |
| Bluetooth |
No |
| WiFi |
No |
| CONNECTIONS |
| Total Analog Inputs |
2 |
| Phono Input |
No |
| Headphone Output |
No |
| Removable Power Cord |
|
| Speaker Connectors |
Binding posts |
| PHYSICAL SPECS |
| Height |
mm (") |
| Width |
mm (") |
| Depth |
mm (") |
| Weight |
— |
| Available Colors |
Black |
| OTHER |
| Parts Warranty |
|
| Labor Warranty |
|
How much power does the Fosi Audio V3 Mono have?
The Fosi Audio V3 Mono delivers 240 watts into 4 ohms with the 48V/5A supply, or 100 watts with the 32V/5A one, per chassis. This is a monoblock: a stereo system needs two. Fosi publishes no 8 ohm rating.
Does the Fosi Audio V3 Mono use vacuum tubes?
No. The Fosi Audio V3 Mono is a solid-state amplifier - there are no vacuum tubes in it.
What amplifier class is the Fosi Audio V3 Mono?
The Fosi Audio V3 Mono uses a Class D amplifier design. Class D is a modern switching design that runs cool and wastes very little energy as heat, which is how makers fit high power into a compact, light chassis.
Does the Fosi Audio V3 Mono have a built-in DAC?
No. The Fosi Audio V3 Mono has no built-in DAC, so a digital source such as a streamer or CD transport needs its own converter, or you connect it over analogue.
Can I connect a turntable to the Fosi Audio V3 Mono?
No. The Fosi Audio V3 Mono has no phono input, so a turntable needs an external phono preamp (or a deck with one built in) before it can be connected.
Does the Fosi Audio V3 Mono have Bluetooth?
No. The Fosi Audio V3 Mono does not have Bluetooth built in; you would need an external Bluetooth receiver connected to one of its inputs.
Does the Fosi Audio V3 Mono have a headphone output?
No. The Fosi Audio V3 Mono does not have a headphone output, so headphone listening needs a separate headphone amplifier.
How much does the Fosi Audio V3 Mono cost?
The Fosi Audio V3 Mono has a manufacturer's list price (MSRP) of $110.
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