This unsurpassed technology is what we call VOLTAiR within our Professional Fidelity series. It lets you enjoy music on the same level as the mastering engineer.


SPL Hermes

Mastering Router with dual Parallel Mix

Hermes revolutionizes Mastering. Now it is possible to route an audio signal through up to eight dual-channel processors in any order. User definable presets allow the comparison of complex processing chains with just a flip of a button.

In addition, Hermes has two integrated parallel mix stages that work with any of the eight processors allowing for comparison of two compressors with different parallel mix settings. The parallel mix stages are stored with the processing chains.

Hermes routing is entirely passive using gas-capsuled and gold-plated high-end relays. All active electronics like the I/O stages and the Parallel Mixes use SPL’s proprietary and unequaled 120V Technology.

Hermes speeds up the workflow in mastering in ways that were previously extremely difficult, and makes the most out of your existing mastering gear. Repatching to hear a simple change is a thing of the past with Hermes – you can change processor sequences on the fly, store them, and compare settings instantly. All with real switches, relays and no software application.



  • Max. Input Level: +32,5 dBu
  • Max. Input Level (Parallel Mix, Gain active): +28 dBu
  • Input Impedance: 20 kOhm (bal.)

Outputs (Speaker Output)

  • Max. Output Level: +32,5 dBu
  • Output Impedance: ‹ 600 Ohm
  • Noise (A-weighted): -121 dBu
  • Noise (A-weighted, Parallel Mix active): -104 dBu
  • Noise (A-weighted, Parallel Mix, Gain active): -102 dBu
  • Crosstalk (at 1 kHz at 0 dBu): -130 dB
  • Crosstalk (at 1 kHz at 0 dBu Parallel Mix active): -110 dB
  • Crosstalk (at 1 kHz at 0 dBu Parallel Mix, Gain active): -80 dB
  • THD & N (at +20dBu): › -112 dBu
  • Common-Mode-Rejection (at 0 dBu): -75 dB
  • Transmission Bandwidth: 10 Hz-200 kHz
    10 Hz = -0,12 dB; 100 kHz = -0,3 dB; 200 kHz = -1,2 dB

Power Consumption:

  • 0,17 Amp, 230V/50Hz, 30 Watt, 37,6 VA
  • 0,34 Amp, 115V/60Hz, 30 Watt, 37,6 VA


  • 230V/50Hz: 1 Amp
  • 115V/60Hz: 2 Amp


  • Standard EIA 19 Inch Housing/2U: 482 x 88 x 300 mm / ca. 19″ x 3,5″ x 11,8″
    (front panel excl.)
  • Weight: 9kg/ 19,84 lb