Hermes

Mastering Router with dual Parallel Mix

Hermes revolutionizes mastering. Now it is possible to have an audio signal processed by up to eight 2-channel processors in any order that can be stored. At the push of a button you can compare up to four complex processing chains.

Connect, route, store, compare

Hermes accelerates mastering workflows in an unprecedented achievable way. The time-consuming replugging of the patchbay alone had made true comparison almost impossible.

Now you can change, store and compare processing chains in seconds. All with real buttons, relays and without additional software.

Simply push the processor buttons A to H in the order in which the audio signal should pass through the processors and store it.

All processors can be named for a better overview. The name always appears briefly in the display when an insert button is pressed.

Free routing of two parallel mix stages

Hermes has two parallel mix stages that can be freely assigned to each of the eight processors and stored with a processing chain.

This means that even two compressors with different parallel mix settings can be compared quickly and easily.

The routing is completely passive with gas-encapsulated and gold-plated high-end relays.

All active stages, such as the input/output stages and the parallel mix stages work in 120V technology.

Sends & Returns

The stereo channels are strictly separated on two boards to achieve the highest possible channel separation.

The inserts are connected with XLRs for the first four stereo processors and with DB25 for the second four stereo processors.

The 120V technology

The 120V technology is our reference technology. The 120V technology is unique in the world. It operates at a DC voltage of 120 volts. This is four times that of IC-based semiconductor op-amps.

The highest possible audio quality requires the highest possible audio operating voltage.

The 120V technology works with +/-60 V. To be able to handle such a high voltage, we have developed special proprietary operational amplifiers that can operate with a DC voltage of +/-60 V: the SPL 120V SUPRA operational amplifiers.

This high voltage would destroy conventional components and operational amplifiers.

 

The 120V technology achieves exceptional technical specifications and sonic benefits. Technically, in terms of dynamic range, signal-to-noise ratio and headroom. Sonically, in terms of richness of detail and an absolutely relaxed listening experience.

By the way, the “120V” in the name of the technology has nothing to do with the local mains voltage from the mains power socket. This is about the operating voltage inside the device with which the audio signals are processed.

 

The mains voltage from the mains power socket is transformed to the required secondary voltage in the device’s internal linear power supply with toroidal transformer. Rectifiers convert this AC voltage into DC voltage required in the audio device.

 

The idea for SPL 120V technology and the SUPRA operational amplifier based on this technology were developed in the 1990s by SPL founder and chief developer Wolfgang Neumann.

 

With the goal of building the best mastering console ever, this basic technological philosophy then took shape for the first time – thus the SPL MMC1 Mastering Console for Galaxy Studios saw the light of day in 2000.

The outstanding sonic and technical features quickly got around in the scene – so further orders were not long in coming.

Besides the MMC 1, another legendary product with 120V technology was created with the PQ, the “King of Parametric Equalizers”.

Since that time, 120V technology has been the foundation for all SPL premium products. Meanwhile, not only for mastering applications, but also for the, studio or hifi use.

 

Comparison

Most audio devices work with an internal operating voltage of +/-15 volts and can thus process a maximum input level of +21.5 dBu. If a DAC, for example, has an output level of +22 dBu at 0 dBFS, level peaks of the music material would already cause overloads in the input stage of the device.

 

All components in the audio device often operate at their limits. The result is an unsteady sound that causes stress and faster ear fatigue.

SPL devices with 120V technology can handle input levels of +32.5 dBu thanks to the higher internal operating voltage of +/- 60 volts – thus offering 12 dB more headroom. All components consequently operate continuously in the optimum operating range. The result is a very pleasant, natural and relaxed sound experience. So you can enjoy your music in every detail.

 

These diagrams clearly show the superiority of the 120V technology in comparison to other circuits with lower, common operating voltages.

In the realm of professional audio mastering, precision, clarity, and reliability are paramount. The SPL Audio Hermes Mastering Insert Router is designed for mastering engineers and audio professionals who demand uncompromising signal integrity and versatile routing capabilities. This unit offers a seamless way to integrate multiple outboard processors into your mastering chain without sacrificing audio quality or workflow efficiency, ensuring that your final mix sounds exactly as intended.

One common challenge in mastering studios is managing multiple analog processors while maintaining a pristine signal path. The Hermes Mastering Insert Router solves this by providing high-quality analog inputs and outputs with maximum gain levels of 32.5 dBu, allowing for compatibility with a wide range of professional equipment without distortion or noise. Its input impedance of 20 kΩ and output impedance of 75 Ω ensure optimal matching with connected devices, minimizing signal loss and preserving sonic detail. This means you can confidently patch in compressors, equalizers, or other processors without worrying about degrading your audio signal.

The frequency range of the Hermes is exceptionally wide, spanning from 4 Hz to 300 kHz (-3 dB), which far exceeds the audible spectrum. This extended frequency response guarantees that no subtle harmonics or transients are lost during signal routing, maintaining the original character of your recordings. The unit’s impressive common mode rejection of -75 dBu and extremely low crosstalk values (-130 dBu without processing, -110 dBu with P-Mix engaged) translate to an incredibly clean signal path with minimal interference between channels. For mastering engineers, this means greater clarity and transparency in the final output, crucial for making nuanced adjustments.

Noise is another critical factor in mastering, where even the slightest hiss or hum can impact the quality of the finished product. The Hermes excels here with an A-weighted noise floor of -121 dBu, rising slightly to -104 dB when P-Mix is activated, ensuring a near-silent background. This low noise performance allows you to work at higher gain settings without introducing unwanted artifacts, preserving the fidelity of your mixes.

Powering the Hermes is an internal linear power supply equipped with a shielded toroidal transformer, delivering stable operating voltages of +/- 60 V for audio circuitry and +12 V for relays and LEDs. This robust design minimizes electromagnetic interference and power fluctuations, further supporting the unit’s clean signal path. With selectable mains voltages for 230 V AC at 50 Hz or 115 V AC at 60 Hz, and corresponding fuse ratings, the Hermes can be integrated into studios worldwide without compatibility concerns. Its maximum power consumption of 40 VA is efficient for a high-performance analog device, ensuring reliable operation during long mastering sessions.

Physically, the Hermes measures 482 mm wide, 88 mm high, and 300 mm deep (19 x 3.46 x 11.8 inches), fitting standard rack systems comfortably. Weighing just over 10.6 kg (23.48 lbs), it is sturdy yet manageable for studio setups. This balanced size and weight make it practical for both fixed mastering suites and mobile studios without compromising build quality.

In practical application, the SPL Audio Hermes Mastering Insert Router is invaluable for mastering engineers who require flexible routing options combined with pristine analog signal quality. Whether you need to switch between different outboard gear, integrate stereo or multi-channel signal paths, or maintain the highest sonic standards, this unit delivers consistent, professional-grade performance. The Hermes ensures that your creative decisions translate into flawless final masters, free from unwanted coloration or noise.

Investing in the SPL Audio Hermes Mastering Insert Router means choosing a tool engineered with meticulous attention to detail and a deep understanding of mastering workflows. Its robust construction, low noise, wide frequency range, and precise routing capabilities equip you to produce masters that meet the highest industry standards. With this unit in your studio, you can confidently deliver mixes that impress clients and listeners alike, making the Hermes an essential cornerstone of any professional mastering environment.