HEGEL 190, 390-400, 590-600

And even more:

”The Hegel H590’s new volume control offers several benefits that enhance its usability and sound quality:
    1.    Digital Control: Unlike a standard potentiometer, the H590 uses a digitally controlled switched resistor network, which provides more precise volume adjustments and reduces potential signal degradation.
    2.    Volume Presets: Users can set a switch-on volume level, ensuring the amplifier starts at a consistent volume every time it is powered on, regardless of the last used setting. This feature helps prevent unexpected loud volumes when turning on the device.
    3.    Maximum Volume Limit: The volume control allows users to set a maximum volume limit, protecting speakers from being overdriven and preventing excessively loud playback that could disturb neighbors or damage equipment.
    4.    Low Distortion and Channel Separation: The custom-designed volume attenuator in the H590 ensures the lowest possible distortion and optimal channel separation, even at low volume levels, contributing to a cleaner and more detailed sound.
These features make the H590’s volume control both user-friendly and capable of maintaining high audio fidelity”. 

“The Hegel H390’s dual mono design, often referred to as dualamp technology, significantly enhances sound quality by providing separate power supplies and circuits for each channel. This setup effectively creates two independent mono amplifiers within a single chassis, which offers several benefits:
1. Improved Channel Separation: By isolating the left and right channels, the H390 minimizes crosstalk between them. This results in clearer stereo imaging and more precise soundstage reproduction.
2. Enhanced Power Delivery: Each channel having its own power supply ensures that they can deliver power independently without interference. This improves the amplifier’s ability to handle dynamic shifts in music with greater control and stability.
3. Reduced Distortion: The separation of channels helps in reducing distortion and noise, leading to a cleaner and more natural sound.
These features collectively contribute to a more detailed and immersive listening experience, distinguishing the H390 from other amplifiers that do not employ such a design”.

I suggest you install the free version of Perplexity AI and do additional research. Please install it from the App Store.  

“The Hegel H400 integrated amplifier, nicknamed “Streamliner,” is designed to deliver exceptional audio quality with a focus on efficiency and user experience.
    •    Power Output: Provides 250W per channel into 8 ohms, ensuring dynamic and precise sound with a damping factor of 4000 for tight speaker control .
    •    SoundEngine2 Technology: Features instant distortion correction, preserving signal integrity and delivering detailed, agile sound .
    •    Dual Mono Construction: Offers superior sound quality through separate power supplies for each channel, enhancing channel separation and reducing interference .
    •    Versatile Connectivity: Supports popular streaming platforms like AirPlay, Spotify Connect, and Roon Ready, ensuring seamless integration with various audio sources”.

Please dont use AI for observations on sound quality or any product comparisons for that matter. Its called LLM (Large Language Model) for a reason. 

1. Limitations of Reasoning

2. Limitations of Expertise

3. Limitations of Understanding

4. Limitations of planning and execution. 

We are several years away from  being able to quote LLM's as a reference.  They are just language models masquerading as intelligence.  Not to mention their penchant for "hallucinating" and making up facts and observations to suit the question.