Sony DAPs have always exhibited a sound signature that is a bit on the warmer end; the NW-ZX507 is no different. Being someone who was never impressed with the NW-ZX300, the NW-ZX507 is a pleasant surprise. It was clear that significant efforts were put in to realise the device to achieve substantial improvements over the NW-ZX300.
It was during the autumn edition of the Tokyo Headphone Festival in 2019 that I first experience the NW-ZX507 when I met up with Sony Engineer Sato Tomoaki on a personal basis to catch up as Sony was not exhibiting. I did not get to experience it again until the review unit arrived at Porta-Fi Experience Lab in January 2020.
Apart from the division of the Audio/Analogue block and the Power/Digital block, the team also implemented four sets of newly developed FT CAP (high polymer capacitor) that are similar to the ones applied on Sony’s DMP-Z1 to strengthen the power supply to the Audio/Analogue block for the balanced output while also increased the capacity of the POSCAP capacitors from 47μF to 100μF to enhance the power supply to the Audio/Analogue block for the single-ended output.
The attention to detail for sound quality doesn’t stop here; efforts were made to strengthen the internal structure of the chassis to improve vibration resistance while a premium, audio-grade lead-free solder with a small amount of gold is used to connects the battery to Electric Double-Layer Capacitors (EDLCs) as well as the headphone jacks.
The Sony NW-ZX506 sports the S-Master HX which is uniquely developed for high-resolution Audio. The digital amplifier amplifies digital signals directly to reduce distortion and noise at wider frequency ranges before converting them into analogue signals which the company claims to maintain the purity of the original signal for more faithful reproduction. The S-Master HX is soldered onto the IC substrates using a high-quality solder specified by Sony.
For those who have non-high-resolution music files particularly MP3s in your collection, the device also features the company’s unique upscaling technology, Digital Sound Enhancement Engine (DSEE) HX that replaces lost high frequencies in real-time, providing near high-resolution sound quality. I am a fan of DSEE HX and have always kept DSEE HX on all my Sony devices.
The NW-ZX507 supports up to 320kHz/32bit PCM audio and Native DSD playback of up to DSD256 (12.288 MHz), formats supported include WAV, FLAC, WMA, MP3, OGG, APE, AAC, ALAC, AIFF, DFF, DSF, and MQA.
I have had the luxury of having the NW-ZX507 for close to 4 weeks and was able to bring it with me for my family trip to the Kyushu region of Japan. It was also featured for an audition to Porta-Fiers during the 14th edition of AudioFriday by Porta-Fi in February 2020.
What impresses me the most about the NW-ZX507 is tonal quality, evident across the frequencies, from the low-end to the mids and the high-end, it is a quality that defines itself from its predecessor.
The low-end has been tuned to portray a character of liveliness with its dynamism coupled with tightness and authority, would win the hearts of many. It certainly provides an element of fun that is engaging, something different from the Sony NW-WM1Z which is my reference DAP at this point.
There is an element of richness in the mid-range. Coupled with the lush and layered details, these together provide character to the musical tones that contribute towards the tonal quality that is so evident in the signature. The NW-ZX507 does have a darker background than the NW-ZX300.
The high-end is free of sibilance and hiss, which is expected of Sony, the tuning is well executed and exhibits clarity with the presence of airiness; however, with a limited amount of sparkles. The improvement in sound quality which the NW-ZX507 has over the NW-ZX300 is significant, however, not substantial enough to eclipse the NW-WM1A and NW-WM1Z of the Signature Series. It has a soundstage that is above average, allowing for excellent imaging and precise instrument separation which is excellent at this price point.
I would recommend an audition on the NW-ZX507 if you are looking to upgrade from an entry-level DAP like the FiiO M7 and the Sony A-Series or an upgrade from the Sony NW-ZX300.