Sound performances
For this review, I chose to pair the Hidizs S9 Pro Plus with the HiFiman Svanar, the FiiO JD7 and the lovely Beyerdynamic’s DT 900 Pro X – the same in-ear/ headphones I used for my KA13 review. If the Hifiman is a bit too high-end for this DAC, the FiiO is more than adequate and should pair quite nicely with the S9, and regarding the Beyerdynamic, I’ve got not much to say: it’s amazing for the price.
As for the source, I kept my MacBook and iPhone and Hidizs default cables + the ddHiFi TC28i. For the files, I mainly used Apple Music Hi-Res stream and Spotify, as I ended up using the S9 Pro Plus almost exclusively on the train, or at the office.
Overall signature
Equipped with the same DAC as the S9 Pro, the Hidizs S9 Pro Plus offers, more or less, the same performance as its predecessor – which isn’t a bad thing by all means.
In fact, paired with the Svanar, in balanced mode, the S9 Pro Plus achieved some impressive results, especially in the higher end of the spectrum, even if power remains a bit too low to properly drive this insane IEM. Paired with the Beyer though, the IEM outputs crystal clear highs and powerful lows, even at low to medium volume levels, in single-ended mode.
Going head to head against its older brother with the same headphones, I couldn’t really discern a significant overall difference. On some tracks, the old S9 Pro seemed to offer a bit more push around 100Hz, while the new S9 Pro Plus appeared more comfortable at higher volumes, but only by a hair’s breadth each time. Listening to my usual test playlist, I could definitely hear the improvement compared to similarly priced dongle DAC though, with cleaner highs and a wider soundstage most of the time.
Most importantly, going balanced definitely make a difference, even more with big cans like the Audeze. To my surprise, the new S9 Pro Plus did sound less powerful than the S9 Pro (not plus) and that was even more audible when compared to the FiiO KA13, which completely outperformed the Hidizs in that regard. Power-wise, the Hidizs S9 Pro Plus was outperformed by almost every FiiO DAC/Amp, but matched the Shanling UA1 Plus and the older FiiO KA1/KA2.
For those seeking power, the KA3 and KA13 remains the go-to pocket DAC for anyone seeking a pocket powerhouse, and the S9 Pro Plus falls a little short in that regard. Still, with the DT700 Pro X, lows were tight and mids sounded organic, close to the original recording – a real magic trick for a DAC this small, and so affordable.
Don’t get me wrong, there’s a lot of power, enough to push big cans like my Audeze LCD-X, or the Meze Liric, but compared to the FiiO, passed 50%, the dynamic range seems to lower even more than before, and I found it harder to discern micro-details. Still, compared to the similarly priced KA1/KA2, the S9 Pro Plus keeps the upper range, and if you pair it with easier-to-drive headphones.
Paired with the FiiO JD7, the combo gives you a perfect mix of accuracy and dynamic, a mix that should accommodate listeners seeking a precise DAC on the go. The perfect mix for newcomers, as the duo appears to be quite forgiving with bad recordings, even more when compared to the FiiO KA13 and KA3. For people that may find the DT 700 Pro X and DT 900 Pro X a tad too dry, this is perfect if you need a small DAC on the go – or don’t get a Beyer, get a Meze.
Of course, compared to Apple’s basic dongle, this is a big improvement. The same can be said when opposed to ddHiFi’s TC35C: better dynamics overall, better bass control, cleaner high-mids, especially with big cans like my Audeze LCD-X. Compared to the new TC44 Pro, and most of all the TC44C, the difference wasn’t as big, ddHiFi latest DAC pushes more dynamic range in my opinion, especially when paired with a good IEM.
In fact, when the TC44C took the lead with classical and electro tracks, like Rezz – Chemical bond, the S9 Pro Plus shined with pop and jazzy songs, like Sun Rai – San Francisco street. The digital filters are a nice addition, but I couldn’t find any real difference in my use, even after days of tweaking. But I know that some of you really have a knack for that feature, so treat yourself.
All in all, this is, unsurprisingly, a good DAC, with no real flaw, sonically speaking, giving you the same level of performance as before. Lovely!
Tonality
Highs: clean and crisp. The S9 Pro Plus has lively treble and with IEMs like the Shanling Sono, it gives tons of details. Going balanced doesn’t make a difference, but I did notice a major difference switching between 16 bit files and 24 bit files on this one, more than I used to hear with other similarly priced DAC. There’s a slight emphasis around 7kHz, but nothing that makes it high-centric. Just feed it with Hi-Res files!
Good test track : Through and through – Leaving Laurel
Mids: open and linear. Vocals and acoustic tracks were an easy job for the S9 Pro Plus, even more so once paired with a good IEM. The soundstage is wide and voices gilded easily into my ears, especially paired with the Shanling ME800. Yet, I preferred the DT900 Pro X with this DAC, as some good pairing occurred, giving me the right amount of details and a wide soundstage..
Good test track: Places – Brace! Brace!
Bass: tight and powerful. Hidizs did a great job here, and the S9 Pro Plus was impressive more than once, especially in balanced mode. In fact, if you paired with a solid can like the Audeze, or the Meze 99 Classics, with a 4.4mm Pentaconn, the difference compared to the single-ended port was stunning. If you like it low, balanced is the go.
Noise and power
Noise: As promised in the product sheet, the Hidizs S9 Pro Plus is absolutely dead silent, even with sensitive IEMs like my Onky. To be sure, I tried various sources to check if EMI shielding was okay too and 99% of the time, I was pleased to hear the same pitch-black background. And this time, even when I took the subway, I never encountered any parasites.
Power: good but not deafening. Hidizs doesn’t offer gain settings with its S9 Pro Plus so all you can do is raise or lower the volume. But, in most situation, the given volume should be enough for almost all and every situation – just don’t try to push big planars with them.
Conclusion
“Third time is the charm”. With the S9 Pro Plus, Hidizs gives us another great addition to the ever evolving S9 range, with a device that doesn’t fundamentally differs from the previous version sonically speaking, but perfects all the other aspects, at an even lower price range.
Sound-wise, compared to the S9 Pro, the Plus version is almost identical, but since the previous DAC already performed pretty well, that’s a good thing. And if the sound prowess were not enough already, you can top that with praise-worthy build quality, a digital filters acces, USB and a conception design that makes it the perfect companion for any of your digital sources – heck, it even works on my XBox.
The perfect choice for anyone seeking a low-priced, mid-range dongle-sized DAC