Allnic ASRA / RHPA-7500 High-Power Headphone Amplifier

1. Pentode · Triode Dual Output Architecture

The ASRA / RHPA-7500 adopts a dual output architecture, delivering
20W in Pentode mode and 10W in Triode mode.

In Pentode mode, the sound emphasizes energy, scale, and authoritative control.
In Triode mode, density, purity, and the refined tonal character unique to vacuum tubes come to the forefront.

Rather than focusing on output figures alone, the core design philosophy of the RHPA-7500 lies in allowing the listener to select the most appropriate drive mode to match the music and the headphones.

2. Permalloy Output Transformer

(Permalloy Output Transformer)

The output stage employs high-purity, nickel-based Permalloy output transformers.

With its exceptionally high magnetic permeability and superior micro-signal responsiveness, Permalloy minimizes coloration and transient delay that commonly occur in conventional output transformers.

As a result, the RHPA-7500 achieves an openness and speed reminiscent of OTL designs, while simultaneously preserving the distinctive texture and tonal richness of vacuum tubes—despite utilizing a transformer-coupled output stage.

3. Dedicated Output for RAAL Ribbon Headphones

Ribbon headphones inherently require dedicated impedance matching and output design.

Rather than treating RAAL ribbon headphones as an exceptional or problematic load, the ASRA / RHPA-7500 formally integrates a dedicated drive circuit, including a dedicated Permalloy output transformer, specifically engineered for RAAL ribbon headphones.

This design allows ribbon headphones to be driven directly and stably without any external interface, delivering fast, transparent high frequencies and outstanding spatial resolution.

4. Versatility Beyond a Headphone Amplifier

In addition to 1/4-inch and 4-pin XLR headphone outputs, the RHPA-7500 is equipped with speaker binding posts, enabling it to directly drive small, high-efficiency speakers.

This amplifier transcends the traditional boundaries between a headphone amplifier and an integrated amplifier, offering an expanded playback platform.

5. Precision Volume Control

(41-Step Constant Impedance Attenuator Option)

The optional 41-step Constant Impedance Attenuator maintains consistent channel balance and tonal density regardless of volume level.

Even during fine volume adjustments, it provides precise control without compromising the sonic character.