Kirstein currently offers 41 products from Fosi Audio. A total of 7 reviews have already been submitted with an average rating of 4,6 out of 5 stars.
Fosi Audio stands for compact HiFi electronics particularly suited to desktop setups and space-saving stereo systems. Its range focuses on HiFi amplifiers, preamplifiers, DACs and headphone amplifiers. Models such as the V3 and ZA3 are designed for classic stereo setups with passive speakers, while devices such as the K5 Pro and ZH3 integrate digital sources and headphones into compact audio systems.
Fosi Audio is characterised by compact enclosures, versatile connectivity and a variety of solutions for building modular HiFi chains. This makes the brand suitable both for listening to music at a desk and for individually configured systems in the living room.
Everything from Fosi Audio at Kirstein
- rn
- Wi-Fi 6 and LAN for stable high-res music streaming rn
- Bluetooth 5.3 with SBC and AAC for flexible source playback rn
- AKM AK4493SEQ DAC for detailed high-res sound rn
- Balanced XLR outputs for clean stereo signals rn
- HDMI eARC and Sub-Out for versatile 2.1 systems rn
- Fosi Audio App with 10-band EQ and Bluetooth remote control rn
- Powerful Headphone Amplification
- Supports High-Resolution Audio Formats
- Versatile Connectivity Options
- Compact and Elegant Design
- Inputs: USB-C, Optical, Coaxial, and 3.5mm Jack
- Outputs: 3.5 mm Headphone Jack, RCA
- Phono input (phono): MM (Moving Magnet) and MC (Moving Coil)
- Output: phono
- Four-step gain setting (38 dB/48 dB/56 dB/66 dB)
- Housing: full aluminum alloy, with enhanced resistance to electromagnetic interference
- Powerful Headphone Amplification
- Supports High-Resolution Audio Formats
- Versatile Connectivity Options
- Compact, Elegant Design
- Inputs: USB-C, optical, coaxial and 3.5 mm jack
- Outputs: 3.5 mm headphone jack, phono
- Value bundle including headphones
- Inputs: 1 x Line In (phono stereo), Bluetooth
- Outputs: Speaker & passive Sub Out (banana plugs, screw/clamp terminals), active Sub Out (phono)
- Bluetooth Version 5.0
- Max. Output Power: 2 x 100W + 50W
- Knobs: Sub Vol, Sub Freq, Treble, Bass, Volume
- Power Amp Chip: TPA3116D2
- Multiple Input Modes (Bluetooth, USB, optical, coaxial, RCA)
- High Output Power with Two TPA3255 Chips
- Power: Up to 165 W per Channel and 350 W for the Subwoofer
- Retro VU Meter for Classic Look and Real-Time Signal Display
- Pre-Out for Additional Amplifiers
- Bass and Treble Controls with Central Locking
- Balanced Dual-Mode Class-D Amplifier
- Modes: Stereo and Mono
- Output Power: Stereo 2 x 155W; Mono 1 x 235W
- Input: phono, XLR, 6.3 mm jack; Output: Stereo, Mono
- Frequency Response: 20 Hz?20 kHz (±0.1 dB)
- Impedance: 2?8 ohms
- 2-piece value set
- Inputs 1/2 for 2 amplifiers
- Outputs A/B for 2 pairs of passive speakers
- Maximum power support: 250 watts at 4 ohms (per channel)
- 2 orange VU meters with adjustable brightness and needle sensitivity
- Idle amplifier protection: Built-in 390 ohm resistor protection
- 4.1 Surround Sound for home theater, TV and gaming
- Fosi HT4S with Bluetooth 5.0, AUX and Toslink
- 4 McGrey bookshelf speakers with 6.5" woofers
- Edifier active subwoofer with 70 W RMS power
- 25 m OFC speaker cable for custom wiring
- Black HiFi set for music, movies and gaming
- Battery Capacity: 2500 mAh (approx. 6 hours runtime)
- Input: 3.5 mm jack
- Outputs: 2x Headphones (3.5 & 6.5 mm jack), Line Out (3.5 mm jack)
- Maximum RMS Power: 2400 mW / 32 Ohm (High Gain), 300 mW / 32 Ohm (Low Gain)
- Robust, High-Quality Aluminum Housing
- Includes USB Cable/Adapter
- Bundle including headphones
- Multichannel Amplifier with Bluetooth Audio
- Total Power: approx. 150 Watts
- 4x McGrey BSS-265 Bookshelf Speakers with 6.5" Woofer
- 1x McGrey CS-440 Center Speaker with 2x 4" Woofers
- Includes PureLink OFC Speaker Cable 25 m
- Clear Surround Sound for Movies, Gaming and Music
- 2.0 amplifier with Texas Instruments 2x TPA3116 chip
- Power: 2x 100 W (4 Ohm)
- 2-band equalizer
- Inputs: Line In (phono), Bluetooth
- Pre Out output
- Frequency response: 20 - 20,000 Hz
- Value bundle including bookshelf speakers and 10m speaker cable
- Ultimate 2.1 amplifier with 2 x 165 Watt
- 2 x Polk Monitor XT15 bookshelf speakers
- Dayton Audio BST-300EX Bass Shaker
- PureLink speaker cable OFC 2 x 2.50 mm², 15 m length
- Versatile inputs: Bluetooth, USB, optical, coaxial, Cinch
- Perfect for home cinema and gaming environments ? sound you can feel
- 2.0 Amplifier with Texas Instruments 2x TPA3116 Chip
- Power: 2x 100W (4 Ohm)
- 2-Band Equalizer
- Inputs: Line In (RCA), Bluetooth
- Pre Out Output
- Frequency Response: 20 - 20,000 Hz
- Compact 2.1 amplifier with 2x165 watts
- 1 pair Polk Monitor XT15 speakers
- Dayton Audio BST-300EX bass shaker for tangible bass
- PureLink OFC 2x2.50 mm², 15 m speaker cable
- Bluetooth and cinch inputs on the amplifier for versatile source options
- Separately adjustable subwoofer frequency (0?300 Hz) & volume for precise bass
- Inputs 1/2 for 2 amplifiers
- Outputs A/B for 2 pairs of passive speakers
- Maximum power support: 250 watts at 4 ohms (per channel)
- 2 orange VU meters with adjustable brightness and needle sensitivity
- No-load amplifier protection: built-in 390-ohm resistor protection
- Power: 2x 165 Watts + 350 Watts Max. (4 Ohms)
- Adjustable Crossover Frequency (0 to 300 Hz), Subwoofer Volume Separately Controllable
- 2-Band Equalizer
- Inputs: RCA, Bluetooth
- Outputs: 3x Speaker Out (L/R, Subwoofer), Pre Out (3.5 mm Stereo Jack)
- Maximum output power: 2 x 105 W at 4 ohms
- Bluetooth, USB, Cinch/Phono, optical and coaxial inputs
- Built-in DAC, preamp and headphone amplifier
- 5654W vacuum tubes and analog VU meter in retro design
- Pre-Out enables convenient setup of a 2.1 system
- Includes remote control plus adjustable bass and treble
Fosi Audio at Kirstein
Fosi Audio focuses on compact audio components for modern HiFi systems. Instead of large enclosures, the emphasis is on space-saving amplifiers, preamplifiers and digital-to-analogue converters. This allows systems to be assembled in a modular way: source, DAC, preamp, power amplification and HiFi speakers can be combined to suit individual requirements. This is particularly useful when desk space is limited or when a stereo system is to be built from individual components.
Amplifiers for passive speakers
A key part of the Fosi Audio range is its compact HiFi amplifiers. Different concepts are available for stereo and mono applications. The V3 is one of the brands well-known amplifier models, while the V3 Mono provides a separate monoblock solution. The ZA3 can be used in either stereo or mono configurations. Fosi Audio therefore offers different ways to build a system combining amplification with passive speakers.
Output power should not be the only consideration when choosing an amplifier. It is also important to consider which inputs are required, which speakers will be connected and whether a stereo amplifier or separate mono solution is better suited to the planned system. Models with Bluetooth are also suitable for setups where music is to be played conveniently from compatible mobile devices.
DACs, preamplifiers and headphone amplifiers
Digital sources such as computers or other compatible playback devices require a digital-to-analogue converter for analogue signal processing. Fosi Audio combines this function with additional features in various devices. The K5 Pro, for example, combines a DAC and headphone amplifier and provides digital and analogue connectivity. The ZH3 is also designed as a desktop solution for DAC, headphone and preamp applications. Devices of this kind are particularly suitable when several functions need to be combined in one compact component.
Preamplifiers, on the other hand, control the signal before it reaches a separate power amplifier or corresponding amplification stage. Fosi Audio offers both transistor and tube-based designs for this purpose. Some models also provide tone controls or allow operational amplifiers to be replaced. This gives users who prefer to configure their system individually the flexibility to match different components without replacing the entire setup.
Fosi Audio for headphones and desktop HiFi
Alongside conventional speaker systems, listening with HiFi headphones is an important part of the Fosi Audio range. Compact headphone amplifiers such as the SK01 and DAC amplifiers including the K5 Pro, DS2 and ZH3 cover different applications. Depending on the model, analogue or digital inputs and different headphone connections are available. The existing sources, headphone connections and amplification requirements are therefore important considerations when choosing a device.
Fosi Audio also offers the i5, an open-back planar magnetic headphone. This extends the portfolio beyond electronics and enables complete combinations of headphones and suitable amplification. Active speakers can also be used in a desktop system, provided that the selected DAC or preamplifier has an appropriate output.
How to build your Fosi Audio system
For a classic stereo setup, a Fosi Audio amplifier and passive speakers form the foundation. If digital sources are to be integrated, a DAC can provide the interface between the source and analogue amplification. A preamplifier can be added for a more modular system. Those who mainly listen with headphones can instead start with a DAC featuring an integrated headphone amplifier. The key is to select components according to their connections, the desired system structure and the requirements of the connected speakers or headphones.
Why buy Fosi Audio at Kirstein?
At Kirstein, you can find Fosi Audio for a variety of HiFi applications – from compact stereo amplifiers and DACs to preamplifiers and headphone solutions. If you are unsure which components are technically and functionally suited to your planned setup, our expert advice can help you make the right choice. Fosi Audio products purchased from Kirstein also come with a 3-year Kirstein warranty.









