Integrated Amplifiers

There are many parallels, beyond form factor, between Eversolo’s Play and WiiM’s ‘Amp’ [HFN Nov ’24], not least in the TI PCM1861 ADC used for their respective line inputs (sampling at 192kHz) and the AKM AK4493SEQ DAC driving a TI ‘PurePath’ Class D power amp module. That said, the Play is a little gutsier than the WiiM Amp, despite both being rated at 2x60W/8ohm. In practice, the Play delivers 74W and 140W into 8 and 4ohm and where the WiiM Amp offered 59W, 110W, 194W and 135W under dynamic conditions into 8, 4, 2 and 1ohm, respectively, the Play thunders out a full 75W, 143W, 279W and 158W [see Graph 1]. So the Play is more capable of driving slightly ‘trickier’ speaker loads despite the uncompensated (reactive) LPF at the output of the amplifier having a very big impact on the overall system frequency response [see boxout].

Distortion is also load and frequency-dependent, rising from 0.0017% through bass and midrange to 0.20%/20kHz (all re. 0dBW), while a persistent white noise holds the A-wtd S/N to 87-88dB via both analogue and digital inputs – the latter’s low-level linearity is held to around 16-bits [red trace, Graph 2]. The digital filter is a fast, minimum phase type with a 69dB stopband rejection and the output is phase inverting. Distortion holds to 0.002-0.056% (20Hz-20kHz, via unloaded speaker outputs at 2V) and falls to a minimum of 0.0018-0.25% over the top 20dB of its dynamic range [again, Graph 2]. Responses are determined by sample rate and load but the ‘default’ 8ohm response extends to +0.7dB/20kHz before falling to –2dB/58kHz and –15dB/100kHz. Finally, jitter is impressively low at 305psec. PM