Integrated Amplifiers

With only minor running production 'tweaks' made to the Vena II's analogue amplifier, it makes sense to focus here on the performance of its new Wi-Fi/network audio feature. In practice, Quad's implementation of the DTS Play-Fi service is superb and, in its 'critical listening' guise, makes full use of the ES9018K2M DAC's capabilities. Jitter is reduced to <20psec via wireless streaming and, relative to a 2V preamp output, the A-wtd S/N ratio is a wide 109dB and distortion just 0.0006-0.0014% (20Hz-20kHz). Importantly, the pattern of distortion does not vary with frequency [see Graph 2, below]. The frequency response, and rejection of alias distortions, is set by Quad's choice of ESS's slow roll-off linear-phase digital filter, now –1.7dB/20kHz, –5.0dB/45kHz and –11.9dB/90kHz with 48kHz, 96kHz and 192kHz files, respectively. This defines the output bandwidth of the Vena II Play when used via any of its digital inputs, the response reaching out 'flatter' and further via the analogue inputs from –0.1/20Hz to –0.5dB/20kHz and –4.7dB/100kHz.

Otherwise, this Wi-Fi enabled version of the Vena II is still rated at 2x45W/8ohm and 2x65W/4ohm. In practice, it still delivers 2x53W/8ohm and 2x75W/4ohm with 68W, 120W and 115W available under dynamic conditions into 8, 4 and 2ohm loads [see Graph 1]. Frequency response, noted above, is slightly more extended than we saw in the Vena II [HFN Jun '19] and this ties in with a welcome reduction in output impedance, down from 0.089-0.125ohm to 0.013-0.045ohm here (20Hz-20kHz). Distortion is largely unchanged at 0.003% through the midrange over its 45W rated output but is slightly reduced at HF from 0.035% to 0.015%/20kHz (re. 10W/8ohm). PM