Slender and lightweight design, Strong output power, Spacious stage, Great dynamics, Superbly linear bass and midrange
Slightly brighter leaning treble won’t suit all, Rubbish included Type-C cable and no Lightning cable in the box, Could do with more fine volume control
The S9 Pro is versatile, nicely resolving and a strong overall package that I can highly recommend.
Hidizs are admittedly a company I have a rocky relationship with though do take note that most of my experience with them was regarding their first product launches, the AP60 and AP200. Their designs are attractive and underpinned by strong specification and reasonable pricing. However, I felt these devices faltered in day-to-day usability and real-world performance. With that said, it has been some time and the company has gone through many product cycles since I last tested their products. The dongle DAC/AMP movement has been strong lately and Hidizs were quick to join the race. In a short time, they are already on their 6th release, each being more highly specced and more refined than the last. The S9 Pro is their latest model and their highest end design to date. It has uncharacteristically high power output for such a compact source and a high-end ESS DAC chip. Moreover, it supports both single-ended and balanced output. At $119 USD, it represents very strong value on paper. Let the testing ensue.
- DAC: ES9038Q2M
- DSD/PCM: Native DSD64/128/256/512, PCM up to 768kHz/32bit
- Output Power: 100mW per channel (32 Ohms), 200mW (32 Ohms Balanced)
- SNR: 120 dB (single-ended), 119 dB (balanced)
- Channel Separation: 80 dB (single-ended), 118dB (balanced)
- Dimensions: 18 x 59 x 8 mm
- Weight: 11g
Behind the Design –
ESS9038Q2M + Discrete AMP
This is ESS’ former flagship 2-channel DAC chip that has now been succeeded by the ES9068AS which represents a very minor spec bump but most notably supports MQA rendering. At present, the ESS9038Q2M remains a very high performing 2-channel DAC with wide codec support including Native DSD64/128/256/512 and PCM 768kHz/32Bit. Usually, this would then be paired with the Sabre9602 amplifier. However, taking a loot at the datasheet, the numbers don’t align so it’s entirely possible that Hidizs are using a discrete setup here. You get excellent power delivery alongside both balanced and single-ended connectivity which is a good bump over most dongle-style DAC/AMPs.
The S9 Pro provides a good unboxing experience and a passable accessory set. It comes in a small hard box that slides open to reveal the device in plastic nestled within a foam inlet. Fabric pull tabs ease the process. Beneath are the accessories, a type-C to type-C interconnect cable, acrylic case with shirt clip and a type-C to USB-A adaptor for use with older PCs. The adaptor is of great quality with a nice aluminium shell, but the interconnect cable could be nicer, this one has a basic construction and is not especially flexible either. I would have liked one of Hidiz’s braided cables at this price point, in addition, no lightning cable is provided so iPhone users will want to factor in the cost of this too.
I quite enjoy the overall design of the S9 Pro, it has slender proportions that are minimise the footprint in the pocket and it’s super lightweight as well. It’s medium sized and on the slimmer side for a dongle, especially one with both single-ended and balanced outputs. While it has the usual glass/aluminium sandwich design one might see on competitors, the protruding jack mounts do give its design some visual flare. Despite this, the feel isn’t quite as premium as many competitors, the finish isn’t as consistent, the glass isn’t curved, and the aluminium frame is boxy. However, all of these are “nice to haves” and don’t irk during daily use; this definitely comes across as a more function over form device.
Besides this, the finish and construction leave little to complain about, there are no obvious points of weakness nor issues that affect its function. The Type-C port is snug and offers a reliable connection, similarly, I experienced no issues with the headphone jacks. Some earlier dongles did have issues here with certain plugs failing to activate the power switch where here, the S9 Pro simply powers on when connected to the source for more reliable operation. The faceplate is adorned with the Hidizs logo and it is backlit by an RBG LED that illuminates to denote power and the resolution of the current audio playing. On the opposite end are both 3.5mm and 2.5mm balanced ports. Note as well a lack of any physical controls, this device is entirely operated by the source device.
The S9 Pro is a simple plug & play device, drivers auto installed on my Windows 10 PC and laptop in a matter of seconds and my Android smartphone connected instantaneously. Once connected, audio playback was fluent with no issues without the installation of a third-party driver.
Lacks Volume Granularity
Once connected, the daily usability is where I have the most complaints. Unlike some competitors, the S9 Pro has no internal volume control, scaling according to the source. With sensitive IEMs, it lacks granularity. This is fine if using a PC where most apps have digital volume control, similarly, listening to music stored on your phone as you have a wealth of apps that offer similar control. However, when streaming such as Spotify, I was left wanting.
Some reviews have mentioned the S9 Pro has a high power draw, and this is something I can also confirm if not to the extent experienced by some others. You can observe that the Hiby FC3 has a relatively minimal impact on power draw as per Accubattery and most competitors occupy a similar ballpark. The S9 Pro is drawing about twice the power on the other hand. For my Xperia 5 II with its 4000mah cell, this was not so much of an issue, however, I can imagine that a phone with a smaller battery could run into difficulties here. Still, to me, this is not bad given it has triple the output power of the FC3.