WestminsterLab Quest preamp and Rei mono power amps
Review organized by Marc Loubeau / Prestige Audio Diffusion
Review sample provided by Prestige Audio Diffusion
Retail prices including VAT:
Quest preamp: 25.490 euro
Option Extended Carbon Pack: 2.690 euro
Option RCA input card: 1.990 euro
Option MC/MM Phono RCA input card: 6.490 euro
Option MC/MM Phono XLR input card: 6.490 euro
Option DS AUDIO Phono RCA input card: 6.490 euro
Rei mono power amp (pair): 36.390 euro
WestminsterLab’s company motto is “Experience music as it is”. In a word, the designers aim to provide the complete music experience. One may ask for specific aspects of music experience – detail, treble, bass, staging, clarity, low distortion, or emotion. As life is – good or bad, newly born or of old age, laughing or crying, up or down, war or peace, love or hate, it is also with music. One may choose either side. WestminsterLab is not choosing any single aspect but instead wants to allow the whole to reveal itself. Beyond this, the company indicates being unable to describe the enigma, indicating that adding more words is totally futile. Instead, they invite us to experience the music as it is.
As an interesting side note, Marc Loubeau, the organizer of the review, told me that WestminsterLab also uses Apogee Acoustics loudspeakers for the development of their electronics. Upon asking, Angus Leung confirms they have a pair of Divas that are indeed used as one of their reference speakers.
The timing of this review could not be more ideal, as I currently have two sets of Apogee speakers available: the Centaur, and the Duetta Signature, both in perfect original condition.
Quest Preamplifier Description
The Quest aims to be the perfect preamplifier to accompany the Rei power amplifier and the company’s cable lineup, completing the connection between your audio source and speakers. It sets out to redefine how a preamplifier contributes to the system and extracts the maximum potential from both the recorded music and the music reproduction system.
During the project’s inception, WestminsterLab extensively questioned the role of the preamplifier in an audio system and challenged whether it was truly necessary. They sought to understand the qualities that an added stage can bring and how it can improve the outcome. With a fresh start, they thoroughly investigated the relationship between the source and the amplifier, carefully examining each preamplifier section to improve every part and explore the synergy between them.
In the early stage of the development of the Quest, it was decided to remove any unnecessary or distracting controls, following the logic of “less is more”, fewer features, in this case, meaning there is less that can affect the sonic performance”. This is why the Quest preamplifier has no buttons on its front panel. The only two switches are underneath, reachable via the bottom: one on the far right for power and one in the middle for the grounding method.
Grounding
The grounding design has a substantial effect on the performance, especially with delicate signals. The company’s Hybrid Grounding feature allows users to switch between two grounding modes, enabling customization for optimal performance. As the manual mentions: “By default, the toggle switch is on Mode I (handle to the right). Mode I is a less aggressive mode in terms of grounding, and it should yield great results with most systems in the world. Mode II (handle to the left) brings more body, texture, speed, and micro dynamics to the music, but it may also bring slightly more noise to some systems”.
Dual Mono Fully Balanced
The Quest preamplifier features a dual mono, fully balanced design that isolates left and right channels for exceptional separation and clarity and minimizing interference and crosstalk.
Precision Volume Control
Signal attenuation is a vital function of a preamplifier, allowing precise control over signal strength. Various methods, such as optical couplers, autotransformers, and resistor ladders, impact sound quality differently. After careful testing, WestminsterLab determined that a shunt-type stepped resistor network was the best choice for their preamplifier design. This system features four channels, each with a 64-step precision resistor network and ultra-low-noise relays, supported by dedicated power regulators and supplies. The control logic is kept simple to minimize interference and enhance sound quality. The preamplifier includes a large LED display that even my aging eyes can easily read sitting 6 meters away and a remote control, avoiding complex circuits that could introduce noise.
Power Supply
The Quest’s power supply is essential for its musical performance, featuring 10 separate power rails designed to isolate different channels and sections. Each rail is customized to meet the specific needs of various components, optimizing performance and minimizing interference for ultra-low noise levels. Dedicated transformers and power supplies for the non-audio sections further prevent noise from affecting audio signals, ensuring sound purity. A 2-stage linear regulation method maintains precise control in critical areas, especially for sensitive components, minimizing distortions.
Both the Quest preamplifier and the Rei mono power amplifiers are fitted with custom solid brass footers with a special anti-oxidization coating.
Compartmentation and Shielding
WestminsterLab has taken extensive measures to protect the fragile signals passing through the Quest. Many signal-handling relays feature a soft start mechanism, and sections within the unit are isolated and compartmentalized, ensuring that cross-interference is minimized.
Customers who want the best of the best can choose to purchase the extended carbon fiber option, which adds an additional layer of carbon fiber shielding inside the unit. As can be seen in the image below, this extra shielding covers the input, output, volume, and power supply sections, and this is said to enhance the background darkness, micro-details, texture, and emotion of the music playback.
Expandability
At the back of the unit are two slots for future expansion modules, allowing users to add custom input functions easily. This design ensures adaptability and compatibility with emerging technologies, enabling users to enhance the unit’s capabilities without needing to buy a new device.
WestminsterLab is proud to collaborate with DS Audio, a leader in cartridge production, to introduce our optical cartridge reproduction. This partnership expands cartridge choices and equalization solutions for DS Audio customers, reinforcing our commitment to exceptional audio experiences.
DS Audio module
The integrated DS Audio module for the Quest features an advanced coupling capacitor and signal-handling technology, ensuring quick response, minimal distortion, and accurate vinyl reproduction. The module has a dedicated power supply for the cartridge’s LED enhances stability, while two built-in high-pass filters—”Disable” and “-6dB (20Hz)”—offer sound customization. Certified by DS Audio, this module guarantees compatibility and performance with DS Audio cartridges.
MM/MC Phono
The phono module features a three-stage amplification design optimized to minimize distortion while seamlessly integrating with the RIAA equalization of each stage. Custom capacitors have been developed specifically for this application to achieve the highest audio fidelity, significantly reducing distortion and coloration.
RCA Input
The Quest provides a fully balanced signal and XLR connectivity, but many iconic audio sources only offer a single-ended RCA output. To bridge this gap, WestminsterLab has developed a dedicated single-ended to balanced converter that preserves the input signal’s unique qualities.
Two Infrared Remote Controls
An infrared remote control is an essential part of any audio product, but in the case of the Quest, which has no buttons, it is particularly vital. This is why WestminsterLab supplies each Quest preamp with two remote control units. This way, there is always a backup. The remote control has been redesigned, and new orders will be fulfilled with a sleeker version with larger flat buttons.
Next: Rei description
