THÖRESS Phono Enhancer - Parametric Phono Equalizer MKII

The THÖRESS Phono Enhancer (Parametric Phono Equalizer MKIII) is a reference-grade, purely active vacuum tube phono preamplifier designed for the most demanding vinyl enthusiasts. Far more than a simple RIAA stage, it offers a unique "on-the-fly" parametric equalization system that allows you to adjust the phono de-emphasis characteristic in real time. This flexibility not only enables the accurate playback of historical pre-1954 record curves (like Decca, Columbia, and EMI) but also serves as a sophisticated, non-destructive tone control to restore tonal balance to poorly mastered or thin-sounding LPs. Built entirely by hand in Germany with point-to-point wiring, it combines a purist Single-Ended Zero-Feedback circuit with the ability to dig deeper into the groove than any fixed-curve phono stage ever could.

Key Features:

• Parametric Phono Equalization: Features three 6-position rotary tone selectors that allow independent adjustment of the bass roll-off, bass turnover, and treble roll-off frequencies to match any historical curve or optimize sound on the fly.
• Purely Active MC Gain: Delivers high-gain amplification for Moving Coil cartridges without the use of step-up transformers, ensuring state-of-the-art signal-to-noise performance.
• Minimalist Topology: Utilizes a purist Single-Ended Zero-Feedback circuit topology employing 2x 12J5GT (or 6J5GT) and 2x PC86 vacuum tubes.
• Versatile Inputs: Equipped with 6 phono inputs (5x MC + 1x MM in standard configuration), allowing multiple tonearms and cartridges to be connected simultaneously.
• Custom Cartridge Loading: Each MC input features specific load impedance settings (100, 200, 300, 500, 1000 Ohms) to perfectly match a wide variety of cartridges.
• In-House Transformers: Powered by an ultra-low noise, low-leakage mains transformer manufactured in-house by THÖRESS to ensure complete mechanical silence and electrical stability.

Beyond RIAA: The "Enhancer" Concept

While the Phono Enhancer performs highly accurate standard RIAA de-emphasis with its controls in the default position, its true power lies in its adaptability. By varying the edge frequencies of the de-emphasis curve via the front-panel knobs, you can subtly boost bass impact, restore midrange presence, or tame excessive treble brightness. This is achieved not through clumsy conventional tone controls that degrade the signal, but by shifting the actual phono equalization parameters. This makes it an invaluable tool for collectors of monophonic LPs, 78s, and early stereo pressings that deviate from the modern RIAA standard.

Active Purity

Unlike many high-end phono stages that rely on passive step-up transformers (SUTs) for MC gain, the Phono Enhancer uses a fully active vacuum tube gain stage. This approach avoids the bandwidth limitations and phase shifts often associated with transformers, resulting in a sound that is open, fast, and dynamically unconstrained. The signal path is kept as short as possible, with meticulous point-to-point air wiring ensuring that every nuance of the cartridge's signal is preserved.

Uncompromising Build Quality

The Phono Enhancer is built to last a lifetime. The chassis is constructed from non-magnetic aluminum with a powder-coated finish and anodized printing, evoking the aesthetic of vintage professional laboratory equipment. Internally, high-grade components like foil-in-oil capacitors and precision resistors are used throughout. The power supply features a hand-wound mains transformer mounted on isolation elements to prevent any mechanical vibration from reaching the sensitive amplification circuit.

The Listening Room Difference

We’re a third-generation family business with a brick-and-mortar showroom in Chestertown, Maryland, and a reputation built on trust, not hype. Whether you’re visiting in person or ordering online, we bring decades of experience, personalized service, and honest guidance to every interaction. We don’t just ship boxes. We help build systems, answer your questions like real humans, and make sure every detail of your setup is right, from the cables to the final connection. Our passion is helping you get the most out of your gear, with support that lasts well beyond the sale.

Specifications