Dual-DAC module for Award-winning Astell & Kern SE180 player offers new upsampling tech
The SEM4 Asahi Kasei AK4493SEQ is the fourth module in the series
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Never shy to try something new, Astell & Kern launched a hi-res music player last year with an interesting USP – interchangeable DAC modules, allowing the owner to personalise the player’s sonic flavour through the optional purchase of removable DAC cartridges. While the player in question, the A&futura SE180 player (£1399 / $1499 / AU$2099), comes boxed with the SEM1 ESS ES9038PRO DAC as standard, there are now three optional modules owners can buy thanks to the all-new arrival of the latest, the SEM4 Asahi Kasei AK4493SEQ dual-DAC.
The SEM4 offers the same 2.5mm, 3.5mm and 4.4mm headphones connections as its siblings (the aforementioned SEM1, the dual SEM2 Asahi Kasei AK4497EQ and the quad SEM3 ESS ES9038Q2M) for wide compatibility of headphone types, but it also brings extra versatility and a new sonic signature to the table.
Most notably, it is the first module in the series to feature Digital Audio Remaster (DAR) upsampling technology, designed to convert whatever file is playing to a higher sample rate at a maximum of 384kHz or DSD256. For example, the module will upsample 44.1kHz and 48kHz PCM files to 352.8kHz and 384kHz respectively, while PCM files over 96kHz will be converted to DSD256, and DSDs below DSD256 will be converted to DSD256 when this option is selected. The result? "A more refined and richer sonic performance," says Astell & Kern.
The DAC module's file support goes beyond those figures even, to native playback of 32-bit/768kHz PCM and DSD512.
The US company’s Velvet Sound technology promises to deliver a more “natural” and analogue-like sonic signature with particularly low distortion, too, while specially selected componentry enables playback for up to 14 hours – the longest among the SE180 modules.
The appeal of a hi-res music player with interchangeable DACs might seem like a niche and expensive concept – and we don't disagree on either point. But whether you'd want to take advantage of the unique versatility on offer or not, the A&futura SE180 player is, regardless, one of the best digital sources around for the money – as its 2021 What Hi-Fi? Award confirms. So if you're in the market for such an item, know that it won't leave you disappointed, or indeed without an upgrade option down the line.
The A&K SEM4 DAC is priced £369 ($400 / AU$579) and will go on sale in May.
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Becky is the managing editor of What Hi-Fi? and, since her recent move to Melbourne, also the editor of the brand's sister magazines Down Under – Australian Hi-Fi and Audio Esoterica. During her 11+ years in the hi-fi industry, she has reviewed all manner of audio gear, from budget amplifiers to high-end speakers, and particularly specialises in headphones and head-fi devices. In her spare time, Becky can often be found running, watching Liverpool FC and horror movies, and hunting for gluten-free cake.
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