Themis is a Class AB analog headphone amplifier and preamplifier designed for systems that require both line-level routing and headphone power delivery from a single board. The standard configuration uses a pre-mounted NE5532 operational amplifier, and the older product overview presents the platform as a design with interchangeable operational cores.

The board operates from dual rails between ±5 V and ±15 V, with ±12 V recommended. It is specified for 5 W program power and 10 W maximum power, with 0.3 W standby power and a minimum recommended supply current of 3 A. The minimum supported load is 16 Ohms, and nominal output current at ±15 V is listed at 0.95 A.

Measured performance focuses on low distortion and controlled output behavior. THD+N is specified at 0.002% at 1 kHz, 32 Ohms, 5 W, while IMD THD is 0.003%. Output gain is +23.5 dB, slew rate is 9 V/us, and output impedance is 3.5 mOhm at 60 Hz into 32 Ohms. Input impedance is 10 kOhm.

The frequency response extends from DC to 570 kHz (-3 dB), with audio-band linearity of ±0.01 dB. Noise performance is specified at 98 dB non A-weighted SNR and 103 dB A-weighted SNR. These figures describe a board intended to function as both a headphone amplifier and a line-stage device without imposing significant bandwidth limitation inside the audio band.

Connectivity includes 2 unbalanced RCA inputs, 2 unbalanced RCA outputs, one 6.3 mm headphone output, and one 3.5 mm headphone output. The board measures 99 mm x 156 mm, placing it in a format suitable for compact integrated analog systems where both headphone drive and preamp functionality are required.

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