Arthur 5523/E1

Refinement everywhere

Our Arthur series aim to use the most refined solutions for electronics, industrial design and build quality. The Arthur 5523/E1 is no exception to this rule.

Purifi Eigentakt technology

For the Arthur 5523/E1 we have chosen to implement the Purifi Eigentakt technology with the 1ET9040BA amplification stage. Purifi is the first company to have managed to build a mathematically exact model for self-oscillating amplifiers. This innovation enables a complete optimization of the amplification circuits improving the performance by an order of magnitude over existing implementations.

In more musical terms:
- Highly resolved and stable stereo image across the whole spectrum, even during very complex and busy passages thanks to the negligible inter-modulation distortion (IMD).
- A total lack of sonic signature, and an ability to reproduce any type of music without preference for genre or production style due to the extremely low THD at any frequency and any power level.
- Difficult loudspeakers are handled with ease, including those that challenge most other amplifiers because of the load-invariant frequency response and negligible output impedance.
- The smallest amount of audible artifacts when pushed into clipping or overload is guaranteed by an exceptionally clean clipping and clipping-recovery in both voltage and current domains.

In the Arthur 5523/E1, the amplification stage can deliver up to 375 W in 8 Ω and 1050 W in 2 Ω.

Exclusive input and gain stage topology

The Arthur 5523/E1 uses the boXem stage III input and gain stage design. It is based on a composite OPA1612/OPA1656 operational amplifier ensuring both ultra low noise and ultra low distortion. It allows a complete transparency of the stage, whatever the gain chosen.

Ultra low noise design

All electronic stages working at signal level are supplied by a combo of LT3045/LT3093 regulators. Not only are they the lowest noise regulators available on the market, but their input supply noise rejection at high frequencies make them ideal when coupled to switch mode power supplies.
In addition, four layers PCBs are used in order to allow circuit routing for the lowest electrical noise possible.

Filtering disturbances

The boXem stage III input and gain buffer integrates an EMI filtering to prevent disturbances from the modern electronics surrounding our interiors.
Moreover, the output of the boXem stage III incorporates a DC filtering system ensuring minimal power on-off noises and speaker lower distortion.

Three levels gain setting

A switch on the rear of the amplifier allows you to set three different levels of gain. Depending on the output capability of your source (pre-amplifier, processor or DAC with volume control) the system gain structure can be optimized for two main targets.
The first is to have the lowest noise, the second the smoothest volume setting as possible.
While the noise levels of modern audio gear has become so low that noise optimization for home audio is often purely academic, having a smooth volume control is something we find so enjoyable that it was our main motivation for integrating the gain control switch.

Quality components

Aluminum chassis, Nextel paint, stainless steel feet, NKK switches, Neutrik, Schurter and WBT connectors. All ensure a perfect touch and feel that will last many years.

Listen to the music, forget the electronics

Plug your audio source (with volume control), your speakers, the mains cable, switch on the mains, and forget your amplifier. The automatic on/off function detects the presence of sound at the input and automatically powers on the amplifier. After 10 minutes without sound at the input, the amplifier sets itself in standby, allowing an ultra-low power consumption when not in use.

Fully protected

A full set of fault diagnostics allows to protect the amplifier and your speakers against abnormalities.

Designed and proudly built in Luxembourg

The Arthur 5523/E1 was designed and is assembled at Schifflange, Luxembourg, at the heart of Europe.