Accuphase: A Legacy of Precision and Musicality
For over half a century, 1972 Accuphase has been synonymous with precision, craftsmanship, an unwavering dedication to sound quality. Accuphase based in Yokohama, Japan.

The company was established with a clear vision: Create audio components that faithfully reproduce music in its purest form. Unlike mass-market brands that evolve with trends, Accuphase has stayed true to its philosophy, refining its designs over decades while maintaining a timeless identity.

What sets Accuphase apart is its meticulous engineering. Every amplifier, preamp, and digital source is the result of careful design, rigorous testing, and an almost obsessive attention to detail. Accuphase products are built to last a lifetime. Their robust construction, modular expandability, and extreme quality control mean that even older models remain highly regarded and sought after.

From the gold-plated circuit boards to a ‘patented’ AAVA volume control, which eliminates traditional potentiometer flaws, each component is crafted to minimize distortion and focus on musicallity. Their class-A and high-bias class-AB amplifiers are praised by many for their effortless, natural sound, combining warmth without loosing clarity.

Accuphase has never rushed to follow industry trends but instead refines and perfects its technology at its own pace, ensuring that every generation of products stands as an improvement over the last.

The appearance of the Accuphase E-800 and E-800S shows subtle refinements, including a larger display and tasteful gold accents on the E-800S.”

Introduction
The Accuphase E-800S is the long-awaited successor to the highly acclaimed E-800, promising further refinement in an already phenomenal Class-A sound experience. While they share a similar foundation, the E-800S introduces several refinements that enhance its overall performance significantly!

The S-variant, introduce seemingly subtle yet meaningful improvements, including Balanced AAVA volume control and an even more powerful power supply. I extensively tested this amplifier with various music genres and several speakers to uncover its true character.

Design and Build Quality
The New E-800S, have subtle design enhancements, like a larger display and gold-plated rings around the input selector and volume knobs. The top panel’s heat dissipation grille has also been redesigned for improved efficiency. Internally, the components have been optimized with larger filter capacitors (63,000µF each) and an enhanced toroidal transformer for even cleaner power delivery.

Volume Control
A notable upgrade in the E-800S is the implementation of Accuphase’s (now) Balanced AAVA (Accuphase Analog Vari-gain Amplifier) volume control system. Unlike traditional potentiometers, the Balanced AAVA adjusts volume by modulating current levels, minimizing signal degradation and mechanical noise. This results in a remarkably low noise floor of 105dB, a 1dB improvement over the E-800.

The E-800S now features a fully Balanced AAVA. This further reduce noise and improve signal integrity. This technology came from their flagship preamp C-3900. It is quite a step up from the former E-800

Now what is AAVA?

AAVA (Accuphase Analog Vari-gain Amplifier) is a different way of controlling volume. Instead of using a resistor to lower the signal, AAVA converts the audio signal into multiple small currents of varying strengths. This process takes place entirely in the analog domain, without any loss of sound quality.

What is the Balanced AAVA in the new E-800S compared to regular AAVA in the E-800 ?
Balanced AAVA is an improved version of AAVA. A balanced amplifier processes sound through two separate signal paths (positive and negative), which helps reduce noise and interference.

What this means is:
– AAVA (single-ended) controls the volume of only one side of the signal (usually the positive signal relative to ground).
– Balanced AAVA controls the volume of both the positive and negative signals separately, resulting in noise reduction and better channel separation. It enhances dynamics & clarity of the sound.

How does a traditional volume control work?
With a standard volume knob (potentiometer), the signal is weakened using a variable resistor. The problem with this method is that it:

– Can adds noise and distortion, especially at low volumes.
– Can cause  channel imbalance, degrading the stereo image (especially on low volumes)
– Causes signal loss because parts of the audio signal are simply blocked.

How does AAVA work differently?
AAVA converts the audio signal into current sources of different strengths. Think of a river splitting into multiple small streams. The number of streams that merge determines how loud the sound becomes.

Step-by-step explanation of AAVA:
– The input signal is converted into current
– Normally, an audio signal remains an alternating voltage, with AAVA, this signal is first converted into current.
– The signal is divided into small current streams.
– AAVA creates a series of 16 or more fixed current sources, each with a specific current value.

These sources have different strengths, such as 1x, 2x, 4x, 8x, and so on (a binary distribution, similar to bits in a computer).

Through an intelligent switching system, these currents can be turned on or off depending on the set volume level.

The total volume is determined by which current sources are active
– If you set the volume to 50%, half of the current sources are activated.
– If you lower the volume, fewer current sources remain active.
– This allows the volume to be adjusted without signal loss or distortion.

The combined signal is converted back into a voltage signal. After mixing the correct amount of current streams, the signal is converted back into a normal analog audio output. Since AAVA has no moving or wear-sensitive parts, there is no mechanical noise like in traditional volume knobs.

The adjustment happens exactly the same for the left and right channels, ensuring a perfect stereo image. Resulting in a extremely low distortion, even at low volumes. 

How do you explain this in a  nutshell, simple explained:
Imagine you have a water tap with 16 small pipes. Instead of a single knob that restricts everything (like a traditional volume control), AAVA can turn each pipe on or off individually to allow precisely the right amount of water (or in this case, audio) to pass through. This makes volume control extremely precise without any loss of quality.

The volume knob
With AAVA, the position of the volume knob is read, but not in the traditional way as with a potentiometer.

Instead of directly changing resistance, the rotation of the volume knob is detected by a sensor. This signal is then used to determine which current sources in AAVA are activated.

The volume knob only sends a command to the AAVA circuit. The actual volume control happens entirely in the analog domain via AAVA. This eliminates noise, wear, and channel imbalance, which are common issues with traditional potentiometers.

In short: the volume knob is simply a controller that determines how AAVA adjusts the volume.

Power Amplification and Performance
The E-800S amplifier employs a dual-mono design with Class-A operation.

– 50W at 8Ω (100W)
– 100W at 4Ω (180W)
– 200W at 2Ω (280W)
– 360W at 1Ω (360W)

The E-800S maintains a high damping factor of 1,000, ensuring tight and controlled speaker response. The power supply in the E-800S has been enhanced with a custom-designed toroidal transformer and larger filter capacitors (63,000µF each, up from the E-800’s 60,000µF). Almost as big as soda cans.

Connectivity and Expandability
Both models offer many connectivity options, multiple RCA and XLR inputs. Even a Home theater pre-input (RCA and even XLR). The E-800S provides two expansion slots for optional modules, such as a DAC or phono stage like the AD-60 or DAC-60, allowing users to customize their audio experience. In The E-800S the Phono cartridge impedance can be controlled from the front, just like the new Accuphase C2300.

The E-800S delivers a sound signature that is both detailed and dynamic. Its Class-A amplification imparts a warm, natural tonality, while the high damping factor ensures tight speaker control and response. The amplifier creates a lifelike soundstage that immerses the listener into a grande music experience.

Why is a high damping factor important?
A loudspeaker functions like an electric motor that moves a cone back and forth. However, when the amplifier stops sending a signal, the speaker cone continues to oscillate. This can make the bass sound bloated, less tight, or dull.

An amplifier with a high damping factor acts as a strong brake, stopping the cone quickly and preventing unwanted resonance. This results in better control over demanding speakers, with low impedance dips.

In a perfect world it seems like you want the highest possible damping factor. Is a high damping factor enough? no certainly not, you hear that in a lot of class D amplifiers, where having a high damping factor, still misses musicality of many AB and definately class A amplifiers..

In a standard Class AB amplifier, the damping factor is usually around 200 – 300, tube amplifiers often have only 10 – 50. Class D amplifiers can sometimes reach 1000+, but they use switching and filtering techniques to achieve this.

Why is a Damping Factor of 1000 in a Class A Accuphase so impressive?
Most Class A amplifiers usually have a lower damping factor

A Class A amplifier operates with a constant current supply, without switching components. This results in highly pure sound reproduction but typically comes with higher output impedance compared to Class D amplifiers. Normally, Class A amplifiers have a lower damping factor (around 100 – 300).

Creating a Class A amplifier with a Damping factor of 1000+ like the E-800S, means they have achieved extremely low output impedance. This is very difficult because:

– Class A designs often produce more heat and energy loss.
– Low output impedance is typically only the domain of Class AB or Class D amplifiers.

This results in superior speaker control, and a warm, dynamic sound, without the cold and digital traits of most Class D amplifiers.

Other tech not even mentioned:
The E-800S operates entirely in Class A and features a six-fold parallel push-pull configuration with high-power MOS-FETs. which is almost fully similar to that used in the A-48S power amplifier and ensures extremely low output impedance.

MOS-FET Switch for Speaker Protection instead of relais switched
Instead of conventional mechanical relays (which can cause signal degration), the E-800S uses a MOS-FET switch for speaker protection. This approach, derived from Accuphase’s flagship models, reduces contact resistance and enhances both reliability and most importantly sound quality.

Advanced Protection Circuits with Optocouplers and Temperature Sensors
The E-800S is equipped with optocouplers and temperature sensors on the heat sinks to enhance safety and reliability. These technologies, derived also from Accuphase’s higher models, ensuring precise detection of abnormal conditions without affecting sound quality.

Now how does the new E-800S sound?

The first thing you notice within seconds of listening to the E-800S is its impressive transparency and improved soundstage. This is undeniably more than just a subtle upgrade over its predecessor, the E-800.

Listening session
To experience the Accuphase E-800S at its best. I paired it with:

– Speakers: Sonus Faber Olympica Nova III and Focal Sopra 2
– Streamer Eversolo A8 + upgraded LHY LPS
– DAC: Chord TT2 + Mscaler, Sbooster upgraded LPS
– Power Filter Audioquest Niagara

Miles Davis – So What

The trumpet’s tone was effortlessly natural, with a warm, full-bodied presence. The upright bass lines were remarkably well-defined, and the air around the instruments created a deep, holographic stage. The E-800S captured every nuance than ever before, from the delicate cymbal brushwork to the subtle variations in Davis’ playing.

John Coltrane – Blue Train

The saxophone had a rich, organic texture, and the piano’s presence in the mix was articulate without being overly bright. The dynamic transitients were smooth, with a sense of realism that made each note feel alive. The soundstage was particularly impressive, placing every musician in their own distinct space. The E-800S really excels to its predecessor, regarding soundstage.

Dave Brubeck – Take Five

The E-800S handled the intricate time signature changes flawlessly, delivering the interplay between the saxophone and drums with stunning accuracy. The brushed drumwork had a tactile presence, and the double bass was deep, yet incredibly precise. This track sounded beyond real.

Melody Gardot – Baby I’m a fool

The E-800S captured the delicate breathiness in Gardot’s voice beautifully, giving the song an intimate, velvety feel. The upright bass was deep and well-defined, and the subtle vibrato in her voice was effortlessly rendered. The amplifier’s sense of space made it feel like a private performance, she was singing just for you.

Stacey Kent – The Ice Hotel

Stacey Kent’s light and airy vocal delivery was crystal clear, with no harshness or coloration. The E-800S rendered the acoustic guitar and piano with an impressive sense of realism, creating a lush and inviting atmosphere.

Emilie-Claire Barlow – Raindrops keep falling on my head

The E-800S captured the light, playful yet detailed nuances in Barlow’s voice with stunning realism. The instruments accompaniment were beautifully layered, with a warm yet airy presence. The amplifier’s spatial precision made the song feel incredibly immersive, as if performed live in an intimate Parisian café.

 

Conclusion
The Accuphase E-800S builds upon the solid foundation of the E-800, introducing refinements that enhance its performance significantly. The E-800S offers a more precise and engaging listening experience, showing once again Accuphase’s commitment to perfection

The Accuphase E-800S is undeniably a masterpiece in the world of integrated amplifiers. The upgrade from standard AAVA to Balanced AAVA results in an even lower noise floor, making music sound clearer and more transparent. The subtle improvements in the power supply contribute to deeper, cleaner, and tighter bass reproduction while maintaining Accuphase’s signature and tonal richness.

I can only recommend the Accuphase E-800S despite it’s steep price. It is an amazing amplifier, when one’s bought can give you enjoyment for many decades to come.

Pros
– Stunning sound quality with unmatched raised clarity and warmth
– Balanced AAVA volume control for an even lower noise floor
– High damping factor, coupled with low output inpedance, resulting in extreme speaker control, without loosing musicality.
– Extremely musical and fluid presentation
– Very high build quality (like al accuphase equipment are)
– Upgrade over the E-800 is clearly noticeable

Cons:
– Runs hot during extended use (which is typical ofcourse for Class-A)
– Large, but not much heavier or bigger than other flagship amps
– Costly, but that is nothing new in Accuphase
– Analogue VU meters are still more nice to see (but that is a personal taste)

Who is the E-800S for?
The purist seeking for the ultimate integrated amplifier without sacrifice, the Rolls Roys of amps. An amplifier with the warmth and musicality of Class-A, without sacrificing detail and dynamics.

Want to experience the absolute pinnacle of Class-A sound? Then the E-800S is among one the best you can get.

Is the E-800S Worth the Upgrade?
The Accuphase E-800S is undoubtedly a masterpiece in the world of integrated amplifiers.

For those who already own an E-800, the question is whether the upgrade is essential? The difference is refined but not groundbreaking. However, for those seeking for that last little bit more air, more stage, and control, it is a personal choice if that is worth the upgrade.

Product page Accuphase E-800S