Pro-Ject MaiA S3 black

Third generation of the compact Austrian integrated amplifier, the MaiA S3 (“My Audiophile Integrated Amplifier”) packs a phono preamp, a digital-to-analog converter, a Bluetooth receiver, a headphone amp, and a power stage into a 20 cm-wide enclosure. All of it in an aluminum chassis barely larger than a paperback book. Pro-Ject uses here the formula that made the previous two generations successful, while redesigning the circuit layout and the enclosure format.

A misleading footprint

The MaiA S3 measures 206 x 55 x 153 mm and weighs just over one kilogram. It fits in one hand. Yet its brushed aluminum enclosure inspires confidence: the connectors are firmly mounted, nothing moves. This new S3 chassis gains a few millimeters compared with the S2, a deliberate choice to improve the layout of the internal circuits and reduce electromagnetic interference. The extra space serves sound quality, not aesthetics. The MaiA S3 comes in black or silver, and it stacks with the other devices in the S3 range (CD Box S3 player, etc.) to form a visually coherent system.

The front panel remains understated: a power button, a 6.3 mm headphone jack, a motorized analog volume potentiometer, and two buttons to navigate between sources. Eight numbered LEDs indicate the selected input. No screen, no menu: simplicity takes precedence. The supplied remote control offers the same functions, with one detail that may be confusing: the left/right buttons control volume, and up/down select inputs, the reverse of the usual convention.

Eight inputs in twenty centimeters

The connector density is the most striking feature of the MaiA S3. On the analog side, there is a phono input compatible with moving magnet (MM), moving iron (MI), and high-output moving coil (MC) cartridges, plus three RCA line inputs. The integrated phono preamp is derived from Pro-Ject’s Phono Box units, a module the brand has mastered for a long time.

On the digital side, the MaiA S3 features one coaxial S/PDIF input and two optical Toslink inputs, all capable of handling signals up to 24-bit / 192 kHz via a Cirrus Logic CS4344 converter. One point to note: the MaiA S3 does not support Dolby Digital or DTS streams. For connection to a television, its audio output will need to be set to PCM.

Bluetooth 5.0 with aptX HD codec (up to 24-bit / 48 kHz) occupies the eighth input. This is an improvement over the S2’s aptX Bluetooth: transmission quality exceeds that of standard CD. The MaiA S3 stores up to eight Bluetooth devices, but handles only one connection at a time.

One drawback compared with the S2: the USB input has disappeared. Connecting a computer directly is no longer possible without using an external USB-to-S/PDIF converter.

Outputs and expansion options

The speaker terminals accept 4 mm banana plugs, spades, or bare wire. A variable RCA pre-out allows connection of a subwoofer or an external power amplifier to strengthen the system. However, there is no integrated active crossover: the subwoofer will have to manage its own crossover point.

The 6.3 mm headphone jack output delivers 2 x 75 mW into 32 ohms and supports headphones with impedance from 16 to 600 ohms. It is a dedicated headphone amplifier, not a simple derivative of the power stage. It performs its function properly for occasional listening, even if the most demanding headphones will reveal its limits.

Dual mono design and sound reproduction

The amplification stage is based on a dual mono topology: each channel has its own circuit, which improves stereo separation (specified at -69 dB at 10 kHz). Power output is 2 x 23 W into 8 ohms, or 2 x 40 W into 4 ohms. On paper, 23 W into 8 ohms may seem modest. In practice, in a medium-sized room (15-25 m²) and with speakers of reasonable sensitivity (85 dB and above), the MaiA S3 fills the space without strain. Distortion remains very low at moderate power (less than 0.04% at 10 W into 4 ohms), and the 97 dB signal-to-noise ratio (101 dB A-weighted) indicates a very discreet noise floor.

The sound signature leans toward precision and liveliness. High frequencies are reproduced with finesse, and the stereo soundstage is well differentiated thanks to the dual mono topology. The MaiA S3 shows control and speed that are surprising for an amplifier of this size: transients are clean, and the bass has weight without dragging. On carefully made acoustic recordings, reproduction is detailed and instruments are placed clearly in space.

On vinyl, the phono preamp delivers a smooth result, with full and generous bass. This is also one of the uses in which the MaiA S3 performs at its best, which is consistent for a Pro-Ject product. Through the digital inputs, the Cirrus Logic converter offers a rendering that is a little warmer and rounder than some more analytical external DACs, a character that may work in its favor depending on taste.

A slight hardness should be noted in some treble with raw or poorly mastered recordings, a trait that can become noticeable during prolonged listening at high volume. And the MaiA S3 does not have the spatial fullness or harmonic richness of much larger and more expensive amplifiers, which remains logical given its format and positioning.

From S2 to S3: what changes

Compared with the MaiA S2, the changes affect several points. The S3 chassis is slightly larger and more rigid, improving shielding. Bluetooth moves from standard aptX to aptX HD (Bluetooth 5.0). The signal-to-noise ratio improves from 90 to 97 dB. The amplification circuit has been completely redesigned with new low-noise components. On the other hand, the S2’s asynchronous USB input (XMOS) has disappeared, and the variable output moves from a 3.5 mm mini-jack to a pair of RCA connectors, better suited to subwoofers and external amplifiers.

Technical specifications

Highlights

• Ultra-versatile all-in-one amplifier
• Dual mono design
• Interference-resistant S3 aluminum chassis
• European manufacturing

Power and audio performance

• Output power
  • 2 x 23 W (8 ohms)
  • 2 x 40 W (4 ohms)
• Frequency response: 20 Hz – 20 kHz (< -0.5 dB @ 4 ohms)
• Signal-to-noise ratio: 97 dB (101 dB A-weighted)
• Harmonic distortion (THD): < 0.04% (10 W / 4 ohms)
• Channel separation: -69 dB @ 10 kHz

Connectivity

• Inputs
  • 1 x Phono (MM / MI / high-output MC)
  • 3 x RCA (line)
  • 1 x Coaxial (S / PDIF)
  • 2 x Optical (Toslink)
  • Bluetooth 5.0 (aptX HD)
• Outputs
  • Speaker terminals (banana plugs, spades, or bare wire)
  • 1 x variable RCA output (subwoofer / external amplifier)
  • 6.3 mm headphone output

Digital section and DAC

• Converter: Cirrus Logic CS4344
• Resolution: up to 24-bit / 192 kHz
• S / PDIF-compatible digital inputs

Bluetooth

• Version: 5.0
• Codec: aptX HD
• Quality: up to 24-bit / 48 kHz

Headphone output

• Power: 2 x 75 mW (32 ohms)
• Supported impedance: 16 – 600 ohms
• Connector: 6.3 mm jack

Power supply and consumption

• Power supply: 20 V / 3 A
• Compatible with 100 – 240 V
• Standby power consumption: < 0.5 W

Dimensions and weight

• Dimensions (W x H x D): 206 x 55 x 153 mm (176 mm with connectors)
• Weight: 1.07 kg (excluding power supply)

Design and manufacturing

• New rigid S3 aluminum chassis
• Available finishes: black, silver
• Designed and manufactured in Europe

Included accessories

• Remote control

Ideal use

• Complete Hi-Fi system without multiplying devices
• Vinyl, digital sources, and streaming
• Compact yet high-performance setup
• Desk, living room, or main system

Key benefits

• Very complete all-in-one solution
• Excellent connection versatility
• High-resolution built-in DAC
• Balanced and dynamic sound
• Compact and elegant format