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Original price was: CAD510.89. CAD413.97Current price is: CAD413.97.
| 500 Units | 2 | 4 | 6+ |
| Discount | -10% | -15% | -20% |
The CP554 is a feature-rich diode bridge compressor that offers a clear tonal response when not operated in vintage mode, providing you with the freedom to maintain sonic clarity when desired.
Incorporating diode bridge circuitry as the gain reduction element adds a touch of harmonic coloration, a characteristic that can enhance your sound and introduce
CP554 employs the specially developed adaptive HRK soft-knee characteristic, created by B. Hrk. This intuitive feature simplifies the use of the compressor, making it accessible to users of all experience levels.
With its user-friendly design, even beginners can produce professional-grade results. The versatile HRK soft-knee curve is impressively musical and adapts seamlessly to a diverse range of music genres and signal types, granting you exceptional flexibility in shaping your sound.
In Vintage Mode, the HRK Custom Analog Circuitry (not a DSP) replicates harmonics closely resembling those generated by the transformers and circuits of classic vintage diode bridge compressors like the Neve 2254, 2264, 33609. This attribute gives you access to analog warmth and character at the flip of a switch.
CP554 is not a clone of any well-known diode bridge compressor. The design of the CP554 is based on engineering principles similar to which were incorporated in the classic or vintage equipment.
The CP554, designed and constructed using traditional methods, offers an authentic analog experience, embodying the golden era of audio processing.
The CP554 is based on the same principles of operation as the NEVE 2254, 2264 and 33609.
All the above compressors use the Diode Bridge as a circuit which controls the level of the signal.
CP554, however, is based on modern components and produces a lot less self-noise compared to vintage NEVE designs. Which means that CP554 is better suited for stereo-bus applications.
Furthermore, CP554 in a default mode produces a far more neutral tonal response and if the NEVE-like character is required, the Vintage Mode can be engaged to add extra transformer harmonics to the signal, providing more flexibility for various studio applications.
The market filled with a multitude of studio-grade compressors, with VCA, FET, and opto-compressors being the most prevalent. In contrast, diode bridge compressors are comparatively rare and expensive, with limited options primarily comprised of AMS-Neve units based on Rupert Neve’s original designs, such as the 2254, 2264, and 33609 stereo compressors.
While some manufacturers attempt to create Neve clones using accessible original diagrams, it is crucial to note that even the most precise clone cannot replicate the original Neve, as the sole source of transformers today is Carnhill, which manufactures transformers based on the original Marinair’s specification, providing only substitutes for Marinair transformers used in classic Neve’s units.
Utilizing a diode-bridge element as the gain control block necessitates a particularly designed circuitry, where the ideal signal symmetry is of utmost importance. In the 60s, only transformers could deliver this perfect signal symmetry.
Traditional diode-bridge compressors are also known for their heightened noise floor. An inadequately designed circuitry can drastically amplify the noise, making the compressor unsuitable for studio applications.
Reproducing Neve’s compressors may be feasible, but it does not guarantee high-quality results. A profound understanding of diode-bridge compressor design is the true key to success.
The CP554 stands apart from mere clones. It is meticulously designed to adhere to the principles of diode-bridge circuitry while striving to achieve optimal performance. CP554 delivers an unparalleled sonic experience, bridging the gap between rarity and excellence for discerning audio enthusiasts.
Introducing Vintage Mode, a proprietary circuitry designed by Bart Hrk that brings the enchanting harmonics of classic diode bridge compressors to life through analog processing circuitry. This fully analog design (no DSP) is rooted in an in-depth understanding of the performance, response, and operation of traditional analog circuitry.
Vintage Mode is the culmination of extensive knowledge of transformers and vintage circuitry, coupled with vast experience in analog circuitry design. This potent combination allows us to faithfully reproduce the distinctive performance, character, and vibe of vintage analog circuitry and transformers. After all, electronic engineering is science, not magic!
The Vintage Mode circuitry promises a response akin to that of vintage transformers, where more signals yield more harmonics. The resultant sonic experience mirrors that delivered by vintage units, complete with their unique frequency and tonal responses.
By default, the CP554 is a neutral and versatile tool. It does not impose any strong character on the musical material, significantly expanding its applicability in studio and music production settings. However, when required, the activation of Vintage Mode introduces classic harmonics, transforming the CP554 into a Vintage Diode Bridge Compressor.
With CP554, you’re investing in a dual-purpose tool, an epitome of modern versatility and vintage charm combined. This 2-in-1 design ensures you have the right sonic character for any situation, making it an invaluable addition to your audio production arsenal.
Traditional passive transformers are known to be vulnerable to electromagnetic interference, such as 50/60Hz hum and HF RF smog. Additionally, their frequency response is contingent upon load and source impedance, which adversely affects the overall performance of analog studio equipment.
The HRK Active Transformer is a game changer that not only resolves the issues associated with passive transformers but also retains and amplifies the desired characteristics of the transformer output stage. This includes the enrichment of harmonic content and the enhancement of tonal response.
What sets the HRK Active Transformer apart is its ability to deliver the rich, beloved sound that audio enthusiasts seek, including the harmonic content and tonal response, while simultaneously eliminating the drawbacks of passive transformers.
| General | ||
| Input Type / Input Impedance | Balanced Electronic | 20k |
| Output Type / Output Impedance | Balanced HRK Active Transformer | Less than 10R |
| Max Output Level | +25dBu@0.1%THD with 1k Load | * Balanced Signal |
| Recommended Load | Balanced 10k | Minimum Supported Load 600R |
| Initial Gain | 0dB | Gain Make-up set to 0dB |
| Phase Reverse | No | CP554 is not introducing phase reverse in any mode of operation. |
| Frequency Response | 5Hz-80kHz@-1dBr | Compressor disengaged. |
| Static Noise Level | -95dBu@10Hz-22kHz | Compressor disengaged. |
| Power Consumption | Typically 45mA per unit | 60mA max. per unit |
| Format | API 500 Format | Compatible with most of the 500 Racks |
| Compressor | ||
| Type of Compressor Engine | Diode-Bridge Symmetric Gain Cell | |
| Compression Curve | Adaptive Soft-Knee | Depends on the Threshold and Ratio knob settings |
| Threshold Range | -25dB / + 20dB | Smooth Continues Potentiometer |
| Ratio Range | 1.5:1 – 8:1 | Smooth Continues Potentiometer |
| Attack Time | 250uS – 100mS | Smooth Continues Potentiometer |
| Recovery Time | 50mS – 2.5S | Smooth Continues Potentiometer |
| Side Chain HPF | 150Hz@6dB/oct | Use the HPF Switch |
| Frequency Response | 5Hz-30kHz@-1dBr | Compressor engaged. |
