HRK EQ522 | 2-BAND GERMANIUM EQUALISER 2025 - NEW

U.S. Import & Tariff Notice for American Buyers

No Section 232 Tariffs Apply / Composite Front Panel

• Zero Aluminum / Composite Front Panel: Please note that the front panel of this API 500-series module is made entirely from a high-grade composite material—it contains no aluminum. As such, this item does not contain aluminum subject to Section 232 tariffs or additional import surcharges when entering the United States from Europe.
• Open-Frame Construction (No Metal Chassis): This unit features an open-frame design consisting solely of the PCB and internal components, without any external steel or aluminum enclosure. It contains no bulk metals that fall under U.S. metal tariff regulations.
• Private Sale Declaration: This item is being sold by a private individual for personal/used gear resale.

U.S. buyers can purchase with confidence knowing this module is exempt from steel/aluminum tariff classifications.

The Definitive Standard for Harmonic Depth and Sonic Provenance

You're not looking at another equalizer listing. You're looking at what happens when discrete military-grade Germanium transistors from the 1960s meet uncompromising modern engineering—and neither side gives an inch.

The EQ522 doesn't "color" your signal. It reveals it. Two separate, fully isolated operational amplifiers—each built around hand-selected NOS Germanium devices that saw their prime during the golden era of studio hardware. Four frequency positions per band. Forty-one stepped positions for surgical control across every adjustment. +/-12dB range without ever reaching for harshness or noise as a crutch. This is the difference between equalizing and sculpting. Between fixing and finishing.

This unit arrives sealed from HRK directly—brand new in original packaging with full documentation. The kind of provenance that doesn't exist anymore because companies like this don't build, package, and ship like this unless they've already decided to close their doors permanently.

THIS ISN'T RESTOCKING. IT'S THE END OF THE LINE.

The HRK Shop is shutting down. Not pausing. Not moving locations. Closing. Every single item remaining on these shelves is extinction stock—once it's gone, the supply chain dies with it and nothing identical will ever be manufactured again.

You're looking at one of the final EQ522 units available anywhere in the world. When this auction ends, there won't be another listing tomorrow or next week from the original source because the source itself ceases to exist. These NOS Germanium transistors aren't sitting in a warehouse waiting for demand—they've been pulled from decades-old military surplus and hand-verified into circuits that are now being assembled until components run out. Then production stops entirely. No reissue. No "classic version" revival three years later with different parts. Just silence.

That's not scarcity as a marketing angle. That's physics. Finite materials, finite labor, zero renewal possible once the shop is dark forever.

A Professional Standard of Excellence
This EQ is not for everyone. It is not for people who are happy with "good enough." This is for the producer who demands perfection. If you are tired of digital gear that sounds fake and plastic, this is your solution. This module is built for those who want real, organic character.

When you add this to your rack, you are doing more than buying gear. You are claiming a professional standard. You are telling the world that your studio uses the best tools available. It gives your music a sense of history and class. It moves you from being a "bedroom producer" to a high-end engineer. This is how you build a signature sound that people will recognize instantly.

A Vanishing Opportunity
When the auction ends, HRK closes permanently and everything vanishes without replacement possibility whatsoever.

Acquire your position now before extinction happens whether you're ready or not—because regret doesn't negotiate timing like opportunity does. Secure this EQ522 while it still physically exists in inventory rather than only in memory afterward when "almost" won't play music through your system anymore.

The Definitive Standard for Harmonic Depth

A sound you do not just hear but feel. Imagine a texture so smooth it adds an immediate sense of weight and space to your mix. This is the resonance of vintage Germanium—a shimmering high-end and a deep, musical low end that transforms a sterile digital recording into a living, breathing performance. As you move through the frequency bands, you will notice an expansion of the soundstage, providing a depth that modern silicon simply cannot replicate.

Technical Specifications
Achieve absolute precision through meticulous engineering and high-value components:

Core Architecture: The Foundation of Your Sound

• Vintage Heart (NOS Military-Grade 1960s Germanium Transistors): We use authentic, hand-selected transistors from the 1960s. This provides a natural, musical harmonic distortion that adds "meat" and "soul" to your tracks without any digital harshness.
• Discrete Design (Two Independent Discrete Opamps): Each channel uses its own dedicated circuit. This ensures maximum signal purity and prevents the sound from becoming "squashed" or compressed.
• Independent Processing (Separate Circuit per Band): By giving each frequency band its own separate discrete opamp, we eliminate inter-band interference. This results in a cleaner, wider stereo image and eliminates phase issues that can make a mix feel muddy.
• Transformer Coupling (Custom HRK Active Transformer): Every signal passes through our bespoke active transformer. This adds incredible "glue" to your mix, making different tracks sound like they belong together in one cohesive, powerful sonic space.

Precision Control: The Power of Exactness

• Tactile Accuracy (41-Position Stepped Potentiometers): These are not standard knobs; they are precision-engineered stepped controls. This allows for absolute repeatability, meaning you can recall your exact surgical settings for every session without ever having to guess.
• High Frequency (HF) Surgical Selection: Four distinct frequency selections (16kHz, 10kHz, 8kHz, 6kHz). Use this to add beautiful "air" and shimmer to vocals or cymbals with total control over the tone.
• Low Frequency (LF) Weight Control: Four precise frequency settings (160Hz, 90Hz, 60Hz, 45Hz). This allows you to sculpt massive weight and foundational warmth into your kick drums and basslines.
• Dynamic Gain Range (+/-12dB): Provides a smooth and musical boost or cut for both bands, allowing you to shape your sound seamlessly.

Signal Integrity & Performance: The Proof of Quality

• Input Impedance (Balanced Input, 20kΩ): Ensures an optimal electrical connection between your gear and this EQ for maximum signal transfer.
• Output Impedance (Balanced Active Transformer Output, <50Ω): A low-impedance output that allows you to drive long cable runs with authority and zero loss in signal quality.
• Ultra-Low Noise Floor (< -90dBu@10Hz-22kHz): Even when the EQ is engaged, your recording remains pristine. You get all of the warmth with none of the unwanted hiss or noise.
• Exceptional Linearity (THD+N < 0.02% @ 1k): This ensures a clean, high-fidelity signal where the only distortion you hear is the beautiful, musical character of the Germanium.
• Extended Bandwidth (10Hz - 60kHz): Provides full-spectrum transparency, ensuring that even the highest frequencies are handled with absolute clarity.
• High Headroom (+24dBu Max Output): Designed to handle professional-level signals, giving you plenty of room to work without fear of unpleasant digital clipping.
• Seamless Integration: Fully compatible with any standard 500 series rack and includes on-board voltage filtering for a stable, noise-free power supply.

Secure Your Studio Standard
As you recognize the unrepeatable value of this opportunity, you will find that securing this piece of audio history is the only logical way to resolve your search for sonic perfection. Do not allow yourself to regret watching another studio claim this unique character. Allow yourself the quality your productions deserve. As you bring this module into your workflow, you will feel the profound satisfaction of knowing your studio has finally reached its full potential.

Acquire the EQ522 and transform your sound forever.