Resonessence Labs Herus USB DAC / Headphone Amplifier

Resonessence Labs

HERUS is our smallest form-factor, audiophile quality USB to Headphone DAC. It uses the USB Audio 2.0 Asynchronous protocol and supports DSD64 and DSD128 as well as high data rate PCM at 24bits up to 352.8Ks/S.

  • It is a USB powered device that achieves more than 100dB of SNR, (typically 108dB) and is capable of driving 2.4V RMS, (ie 6.8V pk-to-pk) into headphones from 600 Ohms to 32 Ohms. The distortion in all cases is better than 0.005% (85dB): the measured THD+N is typically 89dB for 32 Ohms and 90dB (about 0.003%) for 600 Ohms.

    We use Resonessence designed, advanced power line processing circuits that can reliably deliver more voltage range than the USB provided 5V, and we maintain the SNR of the power supply to a degree such that HERUS exhibits well over 100dB of SNR at the headphone output. HERUS also has a very low 0.2 Ohms output impedance that prevents external noise sources coupling into the output.

    All Resonessence products feature upgradable firmware and hardware and despite its physically small size, HERUS also contains Resonessence upgradable hardware and firmware.

  • HERUS is machined from a solid block of aluminum and is 63.5mm (2.5in) long, by 31.7mm (1.25in) wide and 19mm (0.75in) high. It has just two connectors: a USB type ‘B’ socket on one end and a TRS 1/4inch Stereo Headphone connector at the other end.

    HERUS, like all Resonessence products is Designed, Manufactured, Tested and Shipped in Canada.

  • Asynchronous USB Audio 2.0 PCM bit width 24 or 16 Bits (If provided with 24bits HERUS uses them all, but it works with 16 bits also)

    Supported Data Rates:  44.1, 48, 88.2, 96, 176.4, 192 and 352.8 Ks/S

    Supported Formats PCM, DXD and DSD64/128:  Uses DoP protocol 1.1 over USB for DSD

    Operating Systems MS Windows, MAC OS and Linux:  Use the Resonessence Thesycon Driver for USB Audio 2.0 on Windows

    Output Signal Level At Maximum Volume level:  2.4VRMS

    Output Impedance:  0.2 Ohms

    SNR at least:  100dB, Typically 108dB

    THD at least:  85dB, Typically 90dB

    Power:  Into 32 Ohms, 126mW

    THD + N:  0.0035 (89)% (dB) Typical

    Power:  Into 60 Ohms, 95mW

    THD + N:  0.0032 (90)% (dB) Typical

    Power:  Into 300 Ohms, 19mW

    THD + N:  0.0032 (90)% (dB) Typical

    Power:  Into 600 Ohms, 9.5mW

    THD + N:  0.0032 (90)% (dB) Typical