The ZA3 is a stereo power amplifier by Fosi Audio that delivers 180 watts x 2 channels into 4 ohms in stereo, or 235 watts into 4 ohms switched to mono. Fosi publishes no 8 ohm rating. It was released in 2024. It is a 2-channel design using a Class D output stage. Bridged to mono it delivers 235 watts mono into 4 ohms, which is the usual way to use a pair of these on a demanding speaker. Speakers connect via binding posts. A minimum impedance of 2 ohms makes it compatible with a wide range of loudspeakers. The Fosi Audio ZA3 has an MSRP of $150.
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 ZA3 is rated at 180 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:
- 180 watts into 4-ohms
- 106dB Signal to Noise Ratio
Wiring more than one pair of speakers to it? Check the load first →
When pairing the Fosi Audio ZA3 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 ZA3, the next important feature set that you have to evaluate is the input and output selections that it offers.
Fosi Audio ZA3 has total of 2 Analog inputs .
Inputs
- Total Number of Analog Inputs: 2
Outputs
- Speaker Outputs
- Subwoofer Output
Bluetooth Connectivity
Fosi Audio ZA3 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 ZA3. 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 ZA3 doesn't have a phono input so in order to play your vinyl albums, Fosi Audio ZA3 has to be paired with a Phono Preamp that is MM (Moving Magnet) or/and MC (Moving COil) depending on your cartridge type.
Subwoofer Output
Fosi Audio ZA3 has a dedicated subwoofer output which can be used to connect it directly to a powered subwoofer via an LFE(Low Frequency Effects) cable.
Check our
Powered Subwoofers page to find a subwoofer that will work with Fosi Audio ZA3 amp and your speakers.
Balanced connections
Fosi Audio ZA3 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 ZA3 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.
- ✓Signal-to-noise ratio of 106dB, so the amplifier itself should be inaudible between tracks.
- ✓Distortion is specified at 0.006%, an order of magnitude below what is generally held to be audible.
- ✓Can be bridged to mono, so a pair can be used as two larger monoblocks.
- ✓Balanced XLR inputs, worth having on a long cable run.
- ✓At 155mm wide it fits where a full-size component will not.
- ✗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 ZA3 External Dimensions and Weight
Fosi Audio ZA3 has external dimensions of (H x W x D) 2 x 6-1/8 x 7-1/4 inch (50.8 x 154.9 x 183.9 mm ). The unit weighs
1.78 kg (3.9 lbs).
Base Surface Area
Base surface area of an integrated amplifier may become an important decision factor when the space in your room or desk is limited.
The base area of the Fosi Audio ZA3 is approximately 284.9cm2 / 44.2inch2.
- Width: 154.9mm (6-1/8")
- Height: 50.8mm (2")
- Depth: 183.9mm (7-1/4")
- Weight: 1.78 kg (3.9 lbs)
- Base Surface Area: ~284.9cm2 / 44.2inch2
- Volume: ~1.4 liter / 0.4 gallon
Available colors
Fosi Audio ZA3 is available in Black color options.
| General |
| Brand |
Fosi Audio |
| Full Model Name |
Fosi Audio ZA3 |
| Release Date |
2024 |
| Amplifier Type |
Power Amplifier |
| Number of Channels |
2 |
| 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 |
180 watts |
| Bridged Power per Channel |
Yes, 235 watts mono into 4 ohms |
| Frequency Bandwidth |
20 Hz-20 kHz |
| THD |
0.006% |
| Minimum Impedance |
2 |
| Signal to Noise Ratio |
106 dB |
| Digital Music |
| Built-in DAC |
No |
| Bluetooth |
No |
| WiFi |
No |
| CONNECTIONS |
| Total Analog Inputs |
2 |
| Phono Input |
No |
| Headphone Output |
No |
| Subwoofer Output |
Yes |
| Removable Power Cord |
|
| Speaker Connectors |
Binding posts |
| PHYSICAL SPECS |
| Height |
50.8mm (2") |
| Width |
154.9mm (6-1/8") |
| Depth |
183.9mm (7-1/4") |
| Weight |
1.78 kg (3.9 lbs) |
| Available Colors |
Black |
| OTHER |
| Parts Warranty |
|
| Labor Warranty |
|
How much power does the Fosi Audio ZA3 have?
The Fosi Audio ZA3 delivers 180 watts x 2 channels into 4 ohms in stereo, or 235 watts into 4 ohms switched to mono. Fosi publishes no 8 ohm rating.
Does the Fosi Audio ZA3 use vacuum tubes?
No. The Fosi Audio ZA3 is a solid-state amplifier - there are no vacuum tubes in it.
What amplifier class is the Fosi Audio ZA3?
The Fosi Audio ZA3 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 ZA3 have a built-in DAC?
No. The Fosi Audio ZA3 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 ZA3?
No. The Fosi Audio ZA3 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 ZA3 have Bluetooth?
No. The Fosi Audio ZA3 does not have Bluetooth built in; you would need an external Bluetooth receiver connected to one of its inputs.
Can I connect a subwoofer to the Fosi Audio ZA3?
Yes. The Fosi Audio ZA3 has a Yes subwoofer output, so you can add a powered subwoofer to extend the low end below what your main speakers manage.
Does the Fosi Audio ZA3 have a headphone output?
No. The Fosi Audio ZA3 does not have a headphone output, so headphone listening needs a separate headphone amplifier.
How much does the Fosi Audio ZA3 cost?
The Fosi Audio ZA3 has a manufacturer's list price (MSRP) of $150.
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