Network Audio Players/Servers

The Symphonia uses the same ‘125W’ Eigentakt power modules as the A200 [HFN May ’22], albeit here with a ‘high voltage’ ±51V Class AB preamp stage based on the HV and R series. The Class D stage is employed as a current amplifier in this instance, achieving 2x137W/8ohm and 270W/4ohm. The technology dictates that continuous and dynamic power [see Graph 1] are almost identical – 138W, 274W, 565W and 385W into 8, 4, 2 and 1ohm loads, respectively. This is 19.6A into low impedances at <1% THD – higher than the A200’s 12A. Distortion holds to within 0.0005% from 1-110W (re. 1kHz/8ohm) and increases with frequency from 0.0003% midband to 0.0085%/20kHz (re. 10W) but this is still very low – all courtesy of these Eigentakt Class D modules. This module also delivers the load-agnostic ±0.15dB/20Hz-20kHz frequency response and moderate 84.7dB A-wtd S/N ratio (re. 0dBW) that sets the Symphonia, and other ‘Eigentakt adoptees’, apart from the standard Class D pack.

Tested via the preamp outs (2.5V at 0dBFs) the A-wtd S/N is a wide 109dB and distortion low at 0.0035-0.007% [see Graph 2], dropping still further to 0.0002-0.0012% over the top 20dB of its dynamic range (all re. 20Hz-20kHz). Low-level linearity holds true to within ±0.2dB over a 100dB range while jitter is fully suppressed to ~10psec over all sample rates with 24-bit data. Response, and stopband rejection, are entirely determined by the choice of FIR Long, FIR Short, Bezier/ I2S, Bezier and the two NOS (non-oversampling) filter modes. The responses up to 20kHz, 45kHz and 90kHz, respectively, are –0.1dB, –1.0dB and –4.3dB (FIR Long) down to –3.5dB, –3.5dB and –5.7dB (NOS 1 and 2). Stopband rejection is 102dB (FIR Long) to just 1.5dB (NOS). PM