FiiO K19 Review

Today, we’ll take an in-depth look at the K19, FiiO’s new flagship, and a prime example of the company’s engineering expertise.

Over the years, we have reviewed and awarded a lot of FiiO equipment on Headfonia. You can access those reviews through this link: Headfonia FiiO Reviews.

FiiO K19 

The FiiO K19 marks an exciting milestone for the FiiO company, representing a culmination of FiiO’s consistent success across various audio market segments. With the K19, FiiO has designed a flagship device that embodies the literal apex of their engineering, offering the best of their audio technology at a price that remains competitive within the high-end market. Speaking of price, the K19 is priced at $1,350 USD from FiiO’s official AliExpress Store. Here’s a list of the standout features. I had to cut many details from the list as it went on and on. However, we’ll talk more about them in the following sections.

• Dual 8-Channel ESS HyperStream ESS9039SPRO Flagship DACs
• Quad THX AAA 788+ Amp Modules (≈8W @32Ω)
• Fully Balanced Architecture
• Lossless PEQ featuring DEL Tech & DSP
• Dual AccuSilicon Femtosecond Crystal Oscillators
• Quad-core FPGA Signal Processing Center
• x4 WIMA Film Caps & x4 SILMIC II Electrolytic Caps
• x36 MELF Resistors, x8 Panasonic Film Caps
• Silver-Plated OFC Internal Cabling
• 3rd Generation XMOS XU-316 Premium USB Controller
• Qualcomm QCC5125 Bluetooth Chipset
• Bluetooth 5.1 + LDAC 24bit/96kHz, APTX/HD, SBC, AAC
• 32bit 768kHz PCM & DSD512 Support
• Isolated Digital & Analog Sections
• Die-cast Unibody CNC Aluminum Chassis
• 1.3-inch IPS Display & Remote Controller
• FiiO Control App Support
• Upgradeable Firmware + UAC 1.0 & 2.0 Modes for PS5
• & more.

FiiO’s desktop offerings have evolved significantly over recent years, with milestones like the K5 Pro ESS, K7 BT, K9, K9 AKM, and the K9 Pro ESS marking impressive developments. The K19 ascends above these models, setting a new benchmark in desktop audio performance from FiiO. It is also the most powerful and complex device that FiiO has ever designed. You can click on each unit’s name to go to its Headfonia review.

Packaging & Accessories

The FiiO K19 is delivered in a massive two-box carton package, the largest I’ve ever received from FiiO. The outer mailer box is foam-lined to protect the K19’s actual box, which showcases a stylish design with a dark-themed rainbow coating that FiiO has favored since 2021. After 2023, FiiO began to reserve this design for its high-end products. 

The K19’s primary packaging is a thick cardboard box decorated with holographic fractal shapes and “FiiO K19” text in chrome font with a rainbow effect. The unit’s color is indicated in both English and Chinese on the top right. The box’s minimalist design continues on the underside, with only the scratch query sticker, Hi-Res certification sticker, partner logos, FiiO’s address, and a few disclaimers.

When we open the box, we are greeted by a compartmentalized section, first with a soft foam and then with a denser foam underneath. The packaging provides sturdy protection for the K19, with foam covering all four sides of the DAC/AMP. A 12-page quick start guide and warranty card are the first items visible, followed by the K19 and its accessories.

Compared to other DAC-AMPs on the market, the K19 is relatively rich in accessories. The first thing that caught my eye was a headphone stand and a pair of stands that can be attached to the sides of the unit for vertical use. These stands, which look like shark fins to me, can be screwed into the left side panel, allowing the device to be used vertically and saving you valuable desk space. The mounting is done with four screws, and you can mount the feet/stands facing inwards or outwards. FiiO also provides a good quality mini screwdriver with changeable bits to help you mount it. 

Another accessory that immediately catches the eye is the remote controller. The remote controller concept we are used to from companies like SMSL and Topping seems to have found its way to FiiO. I know many of our readers will be very happy about this. This feature will be especially useful for audiophiles who will be pairing the K19 with active monitors or stereo setups. We’ll talk more about the remote soon.

Additional accessories include four extra screws to use with the stands, a 6.35mm to 3.5mm adapter, a C13 power cable, a 1.5-meter USB-A to USB-C cable, and a 1.5-meter USB-C to USB-C cable. You might ask why there are two cables: one connects the unit to your desired source, while the other connects your PC to the DSP. The K19 also comes with six adhesive feet and a 12V trigger cable.

Overall, I’m highly impressed with the accessory package. It befits a premium device like the K19, offering both utility and a touch of luxury. The A-to-C adapter, vertical stand, and removable headphone rack exemplify FiiO’s attention to detail and commitment to user convenience.

Design & Build Quality

The FiiO K19 features a sleek and elegant design, making it the most aesthetically refined model in the K-series. Unlike previous models with bulky toroidal transformers, the K19 introduces an innovative power solution that maintains a slimmer profile without compromising performance. I like the unit’s ability to be used horizontally and vertically, which is quite a practical space-saving solution. I loved this feature with K9-series, and I am glad that FiiO kept this feature.

The K19 has a die-cast aluminum unibody chassis. Its manufacturing process involves precision casting molten aluminum alloy into a meticulously crafted mold. This technique ensures that the chassis is a single, solid piece with exceptional structural integrity and dimensional accuracy. The aluminum not only contributes to the unit’s durability but also provides the best weight-to-strength ratio. Its smooth finish is done through a multi-axis CNC machining process that eliminates imperfections on the surface.

The K19’s aluminum chassis uses a thermally conductive material that directly contacts the internal components, efficiently transferring heat to the vast aluminum frame. The chassis also features a honeycomb mesh design on the top and bottom, enhancing heat dissipation through convection. I noticed that the K19 gets warm to the touch after half an hour. To compare, the surface temp is about the same as K9 Pro ESS. It appears that the aluminum chassis does a great job of heat dissipation. I also noticed that it gets slightly hotter when placed horizontally. Vertical positioning naturally promotes better passive airflow and heat dissipation. If you prefer using the K19 horizontally and want to maximize its cooling potential, consider alternative feet or stands that offer higher clearance underneath the device.

My unit is completely free of any imperfection, which is something FiiO has been very consistent about. The build quality is excellent, from top to bottom. Also, FiiO used NEUTRIK gold-plated XLR connectors, which exemplifies that they wanted the best of everything, including the small details such as these.

Functionally, the K19 is equipped with a comprehensive set of input and output options. It supports six input modes, including USB-C, optical, coaxial, HDMI, HDMI ARC, and Bluetooth, allowing for flexible connections to various audio sources. These inputs are easily managed using the front panel controls, the remote control, or the FiiO Control app. Outputs include 6.35mm unbalanced, 4.4mm balanced, and XLR4 balanced headphone outputs on the front panel and RCA, XLR, coaxial, optical, and HDMI outputs on the rear panel to accommodate a wide range of listening preferences and setup requirements.

The K19 also features convenient enhancements, such as a bi-directional 12V trigger for synchronized device operation and a GND/LIFT ground switch to reduce crosstalk and interference. The front panel features a 1.3” color display that clearly shows playback details and device status, and two knobs allow for easy adjustments. I found the screen slightly small compared to the size of the device, but it works well, providing a scroll-down menu in which you can play with pretty much any setting. We’ll delve into controls soon and go over these in detail. The dual indicator lights on the knobs not only provide sample rate information but can also display various lighting effects that can be customized within the FiiO Control app.

Lastly, there’s a barrel power connector on the rear of the device that can be used if you wish to use your linear PSU with the K19. It allows usage for an alternative DC power supply, with a recommended voltage range of 10V~16V. The device includes internal voltage detection and protection circuitry to safeguard against power anomalies, ensuring reliable operation. FiiO recommends using 15V-3A. The K19 has internal voltage detection and protection circuitry; therefore, the system will disconnect any power supply that exceeds the range. The barrel plug standard for the DC power cord is 5.5×2.1mm.

Overall, the K19 is a splendidly built all-rounder that can be utilized in many audio setups as a sole DAC, PRE, or DAC & AMP. Its rich I/O offers unmatched flexibility in this price range.

The article continues on the next page. Click here or use the buttons below.

Page 1: FiiO, K19, Packaging & Accessories, Design & Build Quality,

Page 2: Technology & Audio Circuitry, PEQ & DSP, Controls & UI

Page 3: Sound Impressions, Low, Mid, High, Technical Capability, Last Words