Heritage Audio Herchild 670N

A Studio Legend Reinvented: The Spirit of the 670, Finally Accessible

For over six decades, the original 670 compressor-limiter has shaped thousands of productions, becoming one of the most iconic dynamic processors ever designed. Yet its reality is also one of extreme rarity: about 500 units produced, with fewer and fewer examples available in working condition. The HERCHILD Model 670 continues this legacy by offering a faithful reproduction, built with a "no compromise" approach, to bring this unique sonic character back to the heart of today's studios.

Who and What It's For: A Reference Compressor for Mixing and Mastering

The HERCHILD Model 670 is aimed at producers, engineers, and artists seeking a very high-level compressor-limiter capable of adding density, cohesion, and that "classy" sense of depth associated with great recordings. Whether on a mix bus, stem processing, vocals, piano, overheads, or an orchestral section, it excels whenever dynamic control is needed without squashing or losing musicality.
Thanks to its extremely low noise floor and high-voltage design, it is particularly relevant in mastering contexts, where even the slightest imperfection becomes audible. You can finely shape dynamics, ranging from subtle compression to more limiting behavior, all while maintaining a stable image and an elegant harmonic signature.

Features and Design: Tube Tradition with Today's Essential Tools

Tube Electronics Engineered for Excellence

Inside, the HERCHILD Model 670 embraces a build worthy of the greatest studio machines: 22 valves and 9 transformers selected to achieve maximum quality. This topology, combined with high-voltage operation, contributes to a solid response, a sense of dimensionality, and the ability to handle high levels with great ease. The result is immediately noticeable in session: no audible "thumps," and a clean sound with very low distortion and noise.

Direct Access to DC THRESHOLD: From Compression to Limiting, Faster and More Precisely

One of the major upgrades in this version is direct access to the DC THRESHOLD, described as a "slope" control. In practice, this control facilitates quick adjustment of the dynamic response, allowing a more natural transition from musical compression to a more restrictive limiting behavior, depending on the program and goal (gluing a bus, controlling a peak, stabilizing a mix, finalizing a master).

Integrated Sidechain Filter: Smarter Low-End Control

Designed for modern environments, the HERCHILD Model 670 includes a Side Chain Filter that is very useful whenever the low end risks over-triggering compression. You gain better control over kicks, bass, and subs while preserving impact and mix clarity. This is especially appreciated on a stereo bus, in mastering, or on sources rich in low-frequency energy.

Dual Mono, Stereo Link, and Mid/Side: A 670 That Adapts to Your Workflow

The HERCHILD Model 670 can be used as two independent processors to treat separate sources or be linked for coherent stereo use. It also supports a Mid/Side mode, increasingly sought after for finely sculpting a master: tightening the center, opening the sides, or controlling the dynamics of the stereo image differently without unbalancing phase and stereo stability.

Manufacturing: 100 Percent Built in Madrid

Entirely designed, wired, and assembled in Madrid, Spain, the HERCHILD Model 670 claims careful manufacturing aimed at professional studios. Every choice supports the same goal: preserving the "high-end" sonic character while offering reliable and relevant use for today's mixing and mastering sessions.

Technical specifications