HIDIZS S9 Pro Plus Review

PACKAGING

The S9 Pro Plus arrives in an eye-catching package, featuring a plastic case. Upon opening the package, we have the a USB Type-C cable, a Type-C to Type A adapter, and, of course, the dongle itself. No instruction manuals are included on the dongle.

 

BUILD QUALITY

The build quality of the Hidizs S9 Pro Plus can be described as average for its price point. Although it is lightweight, there is some noticeable LED bleed on the plastic faceplate, which gives it a somewhat cheap feel. Additionally, the design of the Type-C cable is a bit impractical, as I found that the dongle only functions properly with a specific cable orientation. For it to work without interruptions, the logo should be facing up when connected to the phone. Otherwise, it won't work. Updating the firmware did not help, I believe this is a faulty hardware design that is not very user friendly.

SPECIFICATIONS

• ES9038Q2M High Performance DAC Chip
• PCM Supports Up to 32bit/768kHz
• Native DSD Supports Up to 512
• Physical Buttons for Volume Control & 7 Filter Option
• 4.4mm Balanced & 3.5mm Single-ended Output
• 138mW+138mW@32Ω 3.5mm SE / 180mW+180mW@32Ω 4.4mm BAL
• Sampling Rate Indication RGB Lighting
• Compatible with all platforms: Windows/Mac OS/iPad OS/Android/iOS/Harmony OS
• Hi-Res Audio Certification

FEATURES

IT HAS SEVEN FILTERS! WHO KNEW?

The Hidizs S9 Pro Plus boasts two dedicated buttons, one for volume up and the other for volume down. In addition, there's another feature that may go unnoticed unless you actively look for it online (Thank you, lack of user manual!). If you simultaneously press both buttons, you can access the filter selection, offering a total of seven filter options.

• Anodizing fast roll-off (Default Filter): Vocals are slightly forward, and high frequencies are extended with reduced resonance.
• Linear phase fast roll-off: Enhanced analytical capabilities, delivering a clean and crisp sound.
• Linear phase slow roll-off: Enriched harmonics, full low frequencies, and natural reverb.
• Minimum phase fast roll-off: Balanced and moderate sound.
• Minimum phase slow roll-off: Clean sound with a forward position.
• Hybrid fast roll-off: Soft and smooth sound with enhanced detail.
• Brick wall: Excellent dynamics and strong presence.

The filters didn't introduce any significant changes to the sound, especially if you simply just enjoy listening to it without being overly-critical like an overly obsessed audio-nerd.

IT HAS TWO PORTS!

The S9 Pro Plus is equipped with two headphone jacks, supporting 138mW at 32 Ohms through the 3.5mm port and 180mW at 32 Ohms via the 4.4 balanced port. When connected to the balanced port, it can effectively power the Sennheiser HD600 at approximately 70%-90% volume, being the safest. The S9 Pro Plus demonstrates its capability to drive planar earphones and even hard-to-drive headphones, all within its compact form factor.

DEDICATED COLOR CODE FOR EACH SAMPLING RATE

While not particularly groundbreaking, it's a convenient feature that provides the on-display sampling rate information. This can be considered as an aesthetic enhancement, and it's worth noting that it's a feature found in a few other devices, such as the Audioquest Dragonfly.

• Yellow: DSD 64/128
• Purple: DSD 256/512
• Blue: PCM 176.4/192(kHz)
• Red: PCM 352.8/384(kHz)
• White: PCM 705.6/768(kHz)
• Green: PCM 44.1/48/88.2/96(kHz)

The S9 Pro Plus is lacking MQA support, but it remains a versatile dongle that is compatible with various codecs. If you need a dongle from HIDIZS that supports this codec, you should check out Hidizs XO.

SOUND

While I have strong criticisms regarding the build quality of the Hidizs S9 Pro Plus, it compensates with exceptional sound quality. This device provides ample power to drive both my IEMs and headphones while keeping noise and hissing to a minimum, resulting in a clean, distortion-free audio experience. It truly enhances the audio characteristics of my gears, allowing their strengths to shine at their most decent potential possible. The S9 Pro Plus's sound quality can be described as clean, detailed, and free from any hissing, offering remarkable resolution and a non-fatiguing listening experience with plenty of intricate details. 

HOW ABOUT HARD TO DRIVE HEADPHONES?

Fortunately, my friend loaned me his Sennheiser HD600, allowing me to evaluate it with this dongle. While it may not completely unleash the HD600's potential, as high-end desktop stacks can, the headphones can still be comfortably powered at around 70-80% volume with surprising clarity, resolution, and power. It's important to highlight that for optimal performance, you should connect it to the 4.4mm port, as it doesn't perform well with the 3.5mm port, even at maximum volume, due to a lack of driving power.

COMPARISONS

vs Hidizs XO:

Let's start by comparing it to its sibling first. The Hidizs XO is limited to supporting DSD files up to DSD256, whereas the S9 Pro Plus can handle up to DSD512. While both models deliver a commendable level of clarity and attention to detail, the S9 Pro Plus stands out for its cleaner sound quality without any harshness compared to the XO. It's worth noting that the XO supports MQA, a feature the S9 Pro Plus lacks. In terms of build quality, the XO takes the lead, but the S9 Pro Plus offers independent volume control and capabilities such as the 4.4mm port that the XO doesn't have, making it a versatile choice. The S9 Pro Plus is the clear winner here.

vs Audioquest Dragonfly Red

We must acknowledge that even though it was released in 2012, the Dragonfly Red continues to prove its worth as a reliable dongle. It has truly stood the test of time and holds a special place in my heart. However, when it comes to specifications, the S9 Pro Plus clearly takes the lead. It offers a broader codec support compared to the Dragonfly Red, which is limited to 24-bit/96kHz. Another advantage of the S9 Pro Plus over the Dragonfly Red is its hardware controls and readily available Type-C connection, while the Dragonfly Red relies on a USB-A connection. It's important to recognize that the Dragonfly Red was not originally designed as a mobile phone dongle but rather as a laptop/desktop accessory. In terms of driving power, both dongles can handle the Sennheiser HD600, but the S9 Pro Plus requires less power and, unfortunately, delivers a cleaner and superior output compared to the Dragonfly Red. Don't worry Dragonfly Red, you're still one of my favorite dongles! At least in terms of build quality, aesthetics and sturdiness, you definitely have S9 Pro Plus beat.

vs Fosi Audio DS1

The Fosi Audio DS1 is a dark-horse among many choices in the budget dongle, it has what S9 Pro Plus has to offer except for the filters and firmware support that the S9 Pro Plus has at two and a "half-ish" times lesser the price.  It is more robust, has volume support, and can support up to DSD512. It also sports the same ES9038Q2M ESS DAC. Spec-wise

CONCLUSION

Pros:

• Neutral, clean, sound
• It has a 3.5mm and 4.4mm balanced port
• Provides plenty of power for both ports
• Has physical volume support
• Very portable

Cons:

• Cheap build quality
• The LED bleeding is a personal nitpick
• The filters have no drastic changes
• The USB type-C only works on specific orientations