Integrated Amplifiers

The balanced (XLR) line output is capable of a massive 14.3V (re. 0dBFs) with the volume set to ‘–3.5dB’, beyond which it clips, despite reaching 17.8V at a volume of ‘0.0dB’. Tested at 6V (vol = ‘–11.0dB’), the HA-L7A’s performance is broadly illustrative of what can be achieved with the ES9038PRO DAC although the 214ohm output impedance (increasing to 225ohm/20Hz) is a function of Yamaha’s analogue output stage with its –4.0dB/2Hz HPF. The A-wtd S/N is a superbly wide 118.6dB while low-level resolution is good to ±0.1dB over a full 110dB dynamic range. Distortion falls to as low as 0.00005%/1kHz and 0.0002%/20kHz over the top 20dB of its dynamic range [see Graph 1, below] while jitter is almost entirely suppressed (re. DAC Lock Range = 2) with only a suggestion of low-rate phase noise [see Graph 2]. Correlated jitter is typically <8psec across all sample rates.

The ES9038PRO’s seven familiar filters are available here plus a ‘low latency’ minimum phase type offered by Yamaha. The latter provides a mere 7.8dB stopband rejection and –0.9dB/20kHz, –1.7dB/45kHz and –2.6dB/90kHz responses with 48kHz, 96kHz and 192kHz media, respectively, and is best deployed with higher sample rate material. The ESS DAC’s filters include four linear-phase (Fast, Slow, Apodising and Brickwall), two minimum phase types (Fast and Slow) and one ‘Hybrid’ type. The two Fast filters have similar –0.2dB/20kHz, –0.6dB/45kHz and –1.6dB/90kHz responses with 48kHz, 96kHz and 192kHz media, respectively, with a 75-83dB stopband rejection. The Slow filters trade a limited 14-18dB stopband rejection, and –3.6dB/20kHz (Linear) and –5.1dB/20kHz (Minimum) responses for much reduced time domain distortion. For a full reveal of the HA-L7A’s headphone amplifier performance see boxout. PM