Aurender AP20 Reference All-In-One Music Server

Aurender AP20 Reference All-In-One Music Server

The Aurender AP20 is a reference all-in-one music server that combines Aurender’s network streaming and caching playback platform with a high-resolution DAC, analog preamplifier and powerful integrated amplifier. Designed as a complete high-end music system in a single chassis, it requires only a pair of suitable loudspeakers to provide access to locally stored music, online streaming services and external analog or digital sources.

Unlike conventional streaming amplifiers, the AP20 is built around the same dedicated hardware and software architecture used in Aurender’s reference digital source components. Its dual-mono amplification, relay-controlled analog volume system, dual-mono DAC, extensive linear power supply and expandable internal storage are designed to reduce system complexity without compromising the performance expected from separate high-end components.

Dual-Mono Purifi Eigentakt Amplification

The power amplifier section uses two Purifi Eigentakt 1ET400A Class D amplifier modules in a dual-mono configuration. Designed by Bruno Putzeys, the modules provide high output power, extremely low distortion and strong control of demanding loudspeaker loads.

The AP20 delivers 200 watts per channel into 8 ohms and 350 watts per channel into 4 ohms. A damping factor of 800 and very low output impedance help maintain precise control over the loudspeaker drivers, while substantial dynamic headroom allows the amplifier to reproduce demanding musical passages without losing clarity or scale.

Fully Linear Power Supply with Six Toroidal Transformers

Instead of the switch-mode power supplies commonly used with Class D amplification, the AP20 employs a fully linear power supply built around six separate toroidal transformers. Two 400VA transformers are dedicated to the left and right power amplifier channels, while additional transformers independently supply the DAC boards, processor and FPGA circuitry.

This extensive power architecture helps isolate the audio, digital processing and amplification sections from one another. A total filter capacitance of 80,000µF provides substantial energy reserves, with 40,000µF allocated to each amplifier channel.

Dual-Mono AKM Digital-to-Analog Conversion

The AP20 incorporates Aurender’s reference dual-mono DAC architecture based on two AKM AK4497 converters. Separate digital-to-analog conversion paths for the left and right channels provide excellent channel separation and a low-noise foundation for detailed, transparent playback.

The internal DAC supports PCM audio up to 32-bit/768kHz and native DSD up to DSD512. MQA Full Decoder functionality is also included for compatible files and streams.

Relay-Based Analog R2R Volume Control

Volume is controlled in the analog domain by a relay-based R2R stepped attenuator operating from -64dB to 0dB. This approach avoids relying on conventional digital attenuation and allows the AP20 to preserve signal resolution throughout its usable volume range.

Velocity-sensitive operation provides fine control during slow adjustments and faster level changes when the control is turned more quickly. The integrated preamplifier section manages both the internal digital source and connected analog components.

Pure Analog Pass-Through Inputs

External analog sources can be connected through one balanced XLR input and two single-ended RCA inputs. These connections use a pure analog pass-through signal path without analog-to-digital conversion.

A phono stage, tuner or another analog source can therefore be integrated into the AP20 while preserving the original analog signal. Source selection and volume control remain available through the front panel and Aurender control system.

Digital Inputs for External Sources

The AP20 can also serve as the digital centre of a complete audio system. Its digital inputs include one RCA coaxial S/PDIF connection, one BNC coaxial S/PDIF connection and two optical Toslink inputs.

Compatible CD transports, televisions, media players and other digital sources can use the AP20’s internal precision clocking and dual-mono DAC rather than requiring a separate digital-to-analog converter.

OCXO Precision Clock and Master Clock Input

An OCXO-based precision clock system works together with an FPGA and a jitter-reducing clock generator specified at below 100 femtoseconds. Accurate timing of the digital audio signal helps preserve low-level detail, spatial information and musical coherence.

A 10MHz master clock input allows the AP20 to be connected to a compatible external clock generator, such as the Aurender MC10, for systems requiring an even more advanced digital clocking configuration.

Auxiliary Balanced Output for Subwoofer Integration

A balanced XLR auxiliary output allows a compatible active subwoofer to be added to the system. The AP20 can operate its loudspeaker terminals and XLR output simultaneously by selecting the appropriate output mode in the Aurender Conductor application.

This provides a convenient way to extend low-frequency performance without adding a separate preamplifier or external signal distribution component.

Dedicated Headphone Output

A dedicated 6.5mm headphone output provides personal listening directly from the AP20. The integrated headphone section allows the unit to serve both loudspeaker-based and headphone-based systems without requiring an additional headphone amplifier.

Expandable Internal Music Storage

Two user-accessible 2.5-inch storage compartments allow compatible HDD or SSD drives to be installed according to the required music library capacity. The storage bays can also be left empty when online streaming or network storage is the primary music source.

A separate 480GB NVMe solid-state drive is reserved for the operating system and playback cache. Music selected for playback is cached to solid-state storage, reducing activity from the library drives and providing a stable environment for audio processing.

Music stored on a NAS, external USB hard drive or USB memory device can also be played or imported using the double-isolated Gigabit Ethernet connection and two rear-panel USB 3.0 data ports.

Aurender Conductor and Integrated Streaming

Music selection, library navigation, source management and system configuration are handled through the Aurender Conductor application for compatible mobile devices. The interface provides unified access to internally stored music, NAS libraries, connected USB storage and supported online services.

Integrated streaming includes TIDAL, Qobuz and Internet Radio, together with Spotify Connect and AirPlay compatibility. The AP20 is also Roon Ready and can operate as a certified analog-output endpoint within a compatible Roon system.

Critical Listening Mode

Critical Listening Mode disables the front-panel display, control buttons and non-essential background processes during playback. Reducing unnecessary system activity creates a quieter operating environment for focused listening.

Reference Construction and Wide Colour Display

The AP20 is housed in a substantial machined aluminium chassis fitted with an 8.8-inch wide IPS colour display. Album artwork, track information and playback status are presented at a resolution of 1920 × 480 pixels.

Available in black and silver finishes, the Aurender AP20 provides a complete reference digital and analog playback system for listeners seeking the functionality of a music server, streamer, DAC, preamplifier and integrated amplifier without the complexity of multiple separate components.