IOTAVX SA3

Forty-five watts per channel into 8 Ω, a built-in Wolfson converter, an MM phono input, five line inputs, and a bridged mode: the SA3 packs into a compact chassis everything expected from a versatile stereo amplifier. IOTAVX, a British brand founded by Ian Vermeulen and now operated from Germany by the HifiPilot team, designed this integrated amplifier as a hi-fi hub capable of evolving with the system it powers.

A steel chassis in a compact format

The SA3 measures 43.5 x 7 x 24 cm and weighs 6.5 kg. These dimensions place it in the category of compact integrated amplifiers, but the weight reveals serious construction: the high-rigidity steel chassis protects the circuits from parasitic vibrations, a point often overlooked in this price segment. The front panel includes a readable display, a central volume knob, and a 6.35 mm headphone jack. The screen and LED lighting can be adjusted across ten brightness levels, all the way down to complete shutdown for listening in the dark.

The rear panel groups all connectivity in a well-organized space: five RCA pairs, the phono input, digital inputs, preamp, subwoofer, and speaker outputs, plus control connectors. The standard IEC socket allows the original power cord to be replaced with a higher-quality cable if desired.

Class AB and toroidal transformer

The amplification stage operates in Class AB, a design choice that favors a balance between the signal purity associated with Class A and the energy efficiency of Class B. The high-capacity toroidal transformer ensures stable power delivery, with sufficient current reserve to handle transients without sagging.

The published figures are consistent with this approach: 2 x 45 W into 8 Ω, 2 x 90 W into 4 Ω, total harmonic distortion less than or equal to 0.005%, a signal-to-noise ratio greater than 105 dB, and a frequency response from 10 Hz to 100 kHz (±3 dB). These 90 W into 4 Ω give the SA3 the ability to drive medium-sensitivity speakers in a normal-sized room without running out of breath.

Bridged mode and pairing with the PA3

The SA3 features a stereo/mono switch on the rear panel. In bridged mode, the two channels are combined to deliver a mono signal: 90 W into 8 Ω or 180 W into 4 Ω on a single pair of speakers. The value of this configuration becomes fully apparent with the PA3 power amplifier, sold separately.

The principle is as follows: the SA3 switches to mono mode and powers one speaker (the right channel), while the PA3, also in bridged mode, handles the other speaker via the SA3’s preamp output. The system then provides around 180 W per channel into 4 Ω, which changes the game with current-hungry speakers or in a large listening room. The SA3 retains all its functions (source selection, tone controls, remote control) and serves as the control hub for the duo.

A Wolfson converter for digital sources

The built-in DAC is based on a Wolfson chip (WM8524), capable of processing streams up to 24 bits / 192 kHz. It is fed by two digital inputs: one coaxial S/PDIF and one optical Toslink. This section allows a CD player with a digital output, a network streamer, or a television to be connected without using an external converter.

Wolfson quality, well established in the audio world, gives the SA3 a concrete advantage over entry-level integrated amplifiers that lack onboard conversion. For Bluetooth, IOTAVX offers an optional adapter that attaches to the rear of the device and supports the aptX HD codec. The addition remains optional: those who do not need wireless do not pay for an unused function.

MM phono preamp and tone controls

The MM phono input (2.5 mV sensitivity) includes a dedicated preamp, making it possible to connect a turntable without an intermediate box. The 220 pF input capacitance will suit the vast majority of MM cartridges on the market.

The SA3 offers tone control adjustable in 1 dB steps, up to ±10 dB, for both bass and treble. This fine adjustment makes it possible to adapt playback to a room’s acoustics or to speakers whose response curve could benefit from slight correction. Left/right balance is also adjustable. All these functions are accessible from the front panel or via the supplied infrared remote control.

Connectivity and control functions

On the output side, the SA3 covers the needs of a complete installation: speaker terminals, subwoofer output (for a 2.1 system), preamp output (Pre-Out) for connecting an external power amplifier, and a front-panel headphone jack. The RS-232 port and dual trigger output allow integration into a home automation system or synchronized power-on with other IOTAVX devices. Standby power consumption, below 0.5 W, remains in line with current energy efficiency standards.

Technical specifications

General overview

• Type: integrated stereo amplifier
• Architecture: bridgeable design
• Construction: high-rigidity steel chassis
• Transformer: high-capacity toroidal
• Compact stereo amplifier with high current capacity
• Compatible with medium-sensitivity speakers thanks to its 90 W into 4 Ω
• Upgrade option with the PA3 power amplifier

Amplification and power

• Amplification class: AB
• RMS power into 8 Ω: 2 x 45 W
• RMS power into 4 Ω: 2 x 90 W
• Bridge mode:
  • 1 x 90 W into 8 Ω
  • 1 x 180 W into 4 Ω

Digital conversion

• Built-in Wolfson DACs for precise digital / analog conversion

Inputs

• Analog inputs: 5 x RCA
• Phono input: MM, sensitivity 2.5 mV, built-in MM phono preamplifier
• Digital inputs: 1 x S / PDIF coaxial, 1 x optical Toslink
• Bluetooth: AptX HD compatible via optional IOTAVX Bluetooth adapter

Outputs

• Speaker terminals
• Subwoofer output
• Pre-Out
• Headphone output

Control connectivity

• RS-232 port
• Dual Trigger Out
• Brightness control with 10 levels

Audio settings

• Bass and treble control: ±10 dB in 1 dB steps
• Left / right balance

Audio performance

• Frequency response: 10 Hz – 100 kHz (±3 dB)
• Signal / noise ratio: > 105 dB
• Harmonic distortion (THD+N): ≤ 0.005%

Power supply

• Supply voltage: 115 / 230 V
• Frequency: 50 / 60 Hz
• Standby power consumption: < 0.5 W

Dimensions and weight

• Dimensions (W x H x D): 43.5 x 7 x 24 cm
• Weight: 6.5 kg

Warranty

• Duration: 2 years