a fun and inexpensive "music booster" and try out Feiao K5 Pro

tried Feiao's desktop decoding earpiece was three years ago. One of the opportunities for K5 at that time was to match many portable music players under Feiao such as X7 and X5 II to enhance their thrust. So its most obvious feature is the slot with Micro USB interface, and Feiao player can be directly plugged into it for use. What changes have taken place in my K5 Pro now?

still bears the title of K5, the K5 Pro inherits most of the design elements of the previous work in appearance, the size is basically the same, and the weight is only a dozen grams. What can distinguish the two at a glance is that the body color changes from gray to black, and the Micro USB slot on the top is removed. CNC polished all-aluminum alloy body, the surface is supplemented by anodizing and sandblasting technology, the texture is hard and solid, and the touch is fine.

▲ Large volume knob on the front, with 6.3mm headphone jack and two lever switches on both sides, the latter is used to switch input mode and gain adjustment.

is my favorite design. It is also responsible for the power switch while controlling the volume. During operation, the damping of the knob is moderate, and the sound of "pa" on and off is quite textured. After starting up, the RGB indicator will light up around the knob, the light is soft, the gradient effect, and the visual experience is good. It will light up different colors according to the different sampling rates of the sound source: blue at 48K and below, yellow at 48K and green at DSD. On the right side of the knob is a 6.3mm earphone connector, and there is a 3.5mm to 6.3mm adapter in the accessory, which is convenient for users to connect the most commonly used 3.5mm connector earphone to K5 Pro. There are two lever switches on the left, each with three gears. One is used to select the input mode, including USB DAC, SPDIF IN and LINE IN, and the other is used to select the high, medium and low gains.

▲ The RGB indicator lights around the volume knob will light up in different colors according to the sampling rate of the sound source.

K5 Pro has more interfaces on its back. The coaxial input and optical fiber input interfaces replace the 3.5mm balanced output interface on K5, and the applicability becomes better. RCA line input/output interface and USB-B input interface continue to be retained. Although there is no exclusive base for Feiao player, with the existing interface, users can not only easily connect with various players of Feiao, but also connect various common audio sources including mobile phones and PC. Whether it is used as a desktop USB sound card or a simple earpiece for output, it is very convenient. The matching playing equipment also includes various earphones and active speakers, which is highly playable.

▲ The back is designed with many interfaces, including coaxial input, optical fiber input, RCA line input and line output, USB-B input interface and power supply interface.

The hardware configuration of K5 Pro is the same as that of Feiao. In several parts related to product performance, the combination of XMOS XUF208 USB decoding chip, AKM AK4493 DAC chip, Ti TPA6120 ear amplifier chip and OPA1642 operational amplifier is adopted respectively, and the four-stage professional audio architecture of second-order LPF + analog volume regulation + voltage amplification + current drive is adopted respectively, which supports 768k/32Bit and can hardware DSD512. Feiao also reduced the output impedance of the TPA6120 to less than 1.5 Ω, which increased the output capability of K5 Pro by more than 60%. It can achieve an output power of up to 1.5W under 32 Ω load, and output a swing of 22Vpp under 300 Ω. It is not afraid to drive high-impedance headphones.

▲ There is a 3.5mm to 6.3mm adapter in the accessory, and 4 additional round foot pads are provided.

, I connect K5 Pro to PC through USB interface and use it as desktop USB sound card. The matching earphone is Sennheiser HD600 with impedance of 300 Ω. In this use mode, you need to download the corresponding USB driver from Feiao official website, and then adjust the input mode lever to "①-U. Judging from the sound pressure, it is no problem to push HD600 with K5 Pro. In the case of high gain, the volume knob between 10 o'clock and 11 o'clock is sufficient. The performance under the sound field is an easy part to judge whether the earphone is pushed well.

Under K5 Pro, HD600 has a relatively open sound field in various large-scale symphonies. The sound is not ambiguous. The sense of position between various musical instruments is expressed. At the same time, the overall hearing momentum is relatively sufficient. Specifically for the three frequencies, the HD600 on the low frequency has some sense of arrival, the sense of quantity is not prominent in the headset, and the dynamic is well presented. The mid-frequency human voice part presents a thicker sense of hearing, with a good sense of outline, the sound is close to the ear, and the fine energy-saving of the singer's voice is better displayed. The high frequency has a smooth and pleasant sense of hearing, and the burrs of the sound are polished very smoothly, but at the expense of the extensibility of some going high. On the whole, this set of collocation is not only audible, but also reached a good level.

I also connect with hivi M200 speaker through RCA output interface for audition. Compared with the performance of PC sound card when it is directly connected, M200 shows more sound details under K5 Pro, which is more obvious in the middle and high frequency parts. In many violin solo music, I can capture the rich details of string tremor through M200. The restoration of the human voice is more in place, the outline of the singer is more three-dimensional, the position is also a bit forward, and the listening tolerance is improved. The overall cohesion of the sound has become stronger and the dynamic presentation has become cleaner.

has shed the logo of the "exclusive base" of the previous generation, and Feiao K5 Pro has returned to the role of a common "bridge" between sound sources, headphones and speakers. K5 Pro provides a complete input interface, which can cope with the diversified audio source equipment in the hands of players today. In terms of output, it can not only cope with various earphones such as low resistance and high resistance, but also is a good choice for connecting active Hi-Fi speakers. From the functional point of view, K5 Pro is a traditional desktop decoding ear, but from the design, it is in line with the trend of miniaturization, light weight and fashion of today's equipment. Such a low price, full-featured desktop decoding ear, for players with many devices, will be a highly playable and cost-effective choice.

https://weibo.com/ttarticle/p/show?id=2309404438910859083817Microcomputer Official Microblog11-15 15:18