Aesthetix

Interview with Jim White

The Nirvana Sessions – Jim White (Aesthetix) – August 2023

Principles of Design

Zero Feedback

No Aesthetix product uses feedback, a method traditionally used to compensate for poor design or other anomalies. Aesthetix circuits are designed to measure well without the use of feedback, a difficult endeavor but the results of which are clearly audible.

Differential Amplification

Differential amplifier circuits are used liberally, despite the associated higher cost, because of their inherent advantages of common-mode rejection and greatly reduced ground currents. Special attention is given to the related passive components (resistors, capacitors, etc.) of the differential amplifiers, as these can greatly affect sound quality and stability.

Tube Technology

Aesthetix designs, while primarily vacuum-tube, are technology agnostic. There is no “best” amplifying device; vacuum tubes, bipolar transistors and FETs all have their place and each can achieve stunning results if properly designed and manufactured. That being said, Jim White believes that vacuum-tubes seem to be the best suited for voltage amplification of audio signals, delivering the most neutral, grain-free, full-bodied sound…if properly implemented. Aesthetix uses transistors and other technologies where appropriate; frequently in power supply regulators and power amplifier output stages.

Universal Appeal

Aesthetix aims to create universal products that can perform well anywhere in the world, under virtually any operating condition and in any audiophile system. They accomplish this by manufacturing products that are extremely reliable, with great care given to structural design and integrity and that integrate design features like robust power supplies.

Robust Power Supplies

Thorough power supply design is crucial, and all Aesthetix products have extensive power supplies. Nearly all include choke (inductor) input power supplies which are rarely used in audio due to their precision manufacturing requirements, cost and weight. However, nothing can replace a choke and the benefits they provide, which include improved regulation, a much easier load for the transformer thus reduced current spikes and greater immunity to radio-frequency interference. All Aesthetix products employ discrete regulation for audio circuits and utilise the highest quality electrolytic and film capacitors. Every power supply voltage in an Aesthetix products is carefully regulated to ensure consistent sound quality day-to-day, regardless of ac power conditions.

Circuit Board Design

Circuit board layout and design is also critically important to achieve Aesthetix’s design goals. For example, all Aesthetix preamps and power amps use separate left and right channel audio circuit boards, a technique which prevents cross talk and increases dimensionality and sound staging. Even seemingly minor changes in circuit board layout and trace routing can have a major effect on sound quality and performance. Multiple iterations of circuit boards are common in the design process, each one successively better than the previous.

Damped, Rigid Chassis Design

Structural design is given a lot of attention. Constrained-layer damping, transformer isolation, and other techniques are employed to lower mechanical noise to a minimum. This is part and parcel with an attractive cosmetic design, with form following function to achieve user friendliness and the ability to meld elegantly into any home.

The Different Specifications Explained

The Aesthetix Saturn series of components is available in 3 different specifications, offering you many choices.

Standard

The standard versions are actually far from ‘standard’. Jim White has evolved his circuit designs for many years and changes are only made if they result in significant sonic improvements. So the standard version of a Janus, Calypso, Rhea, Pandora, Romulus or Atlas is a well evolved, field tested and proven, solid, reliable great sounding piece of equipment, designed to deliver a very high standard of sound quality. For those discerning listeners who desire to experience these designs fully optimised, Aesthetix have created two further versions.

Signature

The Standard version is critically acclaimed for its sonic performance and value. However, if the design brief became to produce the very best sound quality possible, the first step would be to replace the critical components with the highest quality components possible. The Signature version is essentially a Standard version with a full component upgrade to the highest level.

The Calypso & Janus Signature uses custom-made inter-stage Teflon hybrid coupling capacitors, replacing the Standard’s polypropylene units, between the gain stage and output stage (2 per channel). The change in these capacitors results in higher resolution, extension, less grain and more air. The 2uF output coupling capacitors (4 per channel) are replaced with 4uF Dynamicaps. This change provides more drive, bass extension, resolution and dynamics while also reducing grain. Highly specialized adjustable air-core capacitors, used primarily in the radio-frequency realm, are installed and adjusted to “tweak” each unit to a rigid standard. The rubber feet are replaced with Harmonic Resolutions Systems’ Nimbus Couplers specially made for Aesthetix. This change results in a lower noise floor and more air and space. The cost of these specialized parts alone is about 1/4 the manufacturing cost of a brand new unit! Any tubes that can be bettered by a special stock of graded and matched tubes are replaced.

The Romulus and Pandora Signature offer true native DSD 1x and 2x functionality over USB. The entire DSP processing section is replaced. The new section includes an advanced Xilinx gate-array which allows the DSP to be completely bypassed for pure DSD 1x and 2x operation. No alteration of DSD data occurs. Many DACs in the market that claim to play DSD actually convert the data to PCM and thereby completely lose the purpose of DSD operation. In addition to the DSP processing section, an entirely new analog board is installed. This new analog board also allows DSD data to pass directly to the DAC, a Burr-Brown PCM1792A running in pure differential mode. Extremely low noise, high linearity Vishay Z-foil audio resistors are utilized in the critical current-to-voltage conversion stage.

The Signature versions have improved tonality, frequency extension, air and space around each note and emotional expression. The artist or performance has more presence, more body and naturalness. Singers have more of a chest, throat and character in their voice.

Eclipse

The Eclipse version is the ultimate expression of the Aesthetix Saturn concept. The Janus & Calypso Eclipse internal changes begin with .22uF / 600V Stealth coupling capacitors used between the second and third gain stages, and the third gain stage and output stage of the phono section. Two more are used between the gain stage and output stage of the line section, per channel. Twelve total of these exotic capacitors are used. There are four 2uF / 400v coupling capacitors used in each channel of the output stage of the Janus. In the Eclipse version, these are replaced with Stealth copper foil 4uF/400v, improving low frequency response.

High frequency tuning capacitors are installed and hand-adjusted to tailor the frequency response to a tight .1dB standard. The high voltage transformer, heater transformer and high voltage choke are all re-installed on isolation mounts. Harmonic Resolutions Systems’ Nimbus Couplers specially made for Aesthetix replace the four rubber feet of standard units. The new power supply is installed with enhanced ventilation. Additional damping material is added to key chassis points. A single point ground system is used to ground the transformer cases as they are no longer electrically grounded to the chassis via physical contact due to their isolation mounts. All Eclipse Rhea, Calypso and Janus units receive a new power supply which has been refined by improved trace routing to further reduce extraneous noise.

Sonically, the Eclipse versions have a much lower noise floor with more musical detail & nuances being perceptible. There is also greater clarity, openness and immediacy. Absolutely superb!