QULOOS QLS QA390LE

From the first limited edition product QA360LE released by QLS fiver years ago to the introduction of the second limited edition today, Clark has been improving the product 's sound quality during use this standard version. If the improved sound has achieved the level that he couldn’t wait to share, we might launch the modified edition in the market. Since Clark has been using some non-mass production techniques with low efficiency, we have to use more human resources and only provide limited products, in order to maintain high-quality sound.

Two years after the QA390 standard edition released to the market, the QA390LE (limited edition) emerged. Although it is coincidental and lucky that we can make such great sound improvements, we will definitely deliver more mature products with better sound effect through the long-term try and modify of Clark.

What does the limited edition upgrade?

Global Clock

Upgrade to AS338, the jitter has been reduced from 88fs to 38fs, thus greatly improving low-frequency quality in hearing, providing impressive and majestic low-frequency heavy sound..

Alternative DAC

The AK4497 that has halted production is replaced by ES9038PRO. Due to the honing more than a year, the alternative chip can bring excellent sound quality and audio experience.

Upgraded Bluetooth

It is compatible with more encoding formats. Through optimized design, the AS338 global clock is used to recollect data. After upgrade, the sound input through Bluetooth is better than the internal SD card played by the standard edition.

Power Optimization

It compensates the frequency bandwidth of super-capacitor, reduces the power supply internal resistance, and increases the power isolation of digital circuit and analog circuit, to improve the dynamic feature, ductility and permeability of sound.

Analog Circuit

It optimizes analog circuit design and component selection again, further improves sound density and details, and provides more open sound scenes and better sound with sense of depth, stereo and space.

Readjust sound

It collects feedback concerning the standard edition, and conducts a second toning to make the sound more complete. It focuses on the musicality, freshness, true nature and fullness of music, and ensures that music can be listened to for a long time without being annoying.

The sound of the limited edition is not the simple upgrade of that of the standard edition QA390, It’s more like a brand new product with completely different sound levels. The limited edition provides fresh sound with first-class musicality. Its full and heavy mid-low frequency sound is rather impressive. The exquisite sound effects make people feel like being in a concert scene.. Most importantly, it can present the sound with great momentum and dynamics that seemingly do not match its appearance. It’s a device that can enable people totally lost in music.

Power circuit design that is lower than battery noise

The noise of this chip is only 0.8μVRMS, which is much lower than the noise when the battery is working (the noise is about 2.7uV when the 3.7V lithium battery has a 500mA load). At the same time, the chip has a low frequency of nearly 100dB and a high of 76dB at 1MHz. The power supply ripple rejection capability eliminates interference from power supplies.

Can be used as a relative reference standard for ideal sound

Unconstrained by the volume, the battery generates a set of desktop-level isolated regenerative power supply, which solves the problem that the traditional AC power supply is affected by the power environment, making the sound more stable and stable, so that all users can hear the sound we want to express.

The QA390's battery-powered sound is largely unaffected by any external factors and is ideal as a relative reference for good sound.

Two super capacitors, supplemented by multiple isolated ultra-low noise power circuits

Dual 1000000uF low internal resistance super capacitor support for digital and analog partial isolation power supply, similar to desktop dual transformer design

Completely different from the battery circuit of the portable

Most of the batteries used in portable players are limited to 2 ~ 3A, which makes the sound scale, dynamic and momentum less natural than desktop players. The battery used in the QA390 can achieve a single discharge current of 10A, and we use multiple parallels to further reduce the internal resistance while the current capability is several times. This current explosive force exceeds many machines that use 220V power supply.

In addition, the analog and digital inlets of the power supply circuit each have a 1000000uF super capacitor, which provides further protection for the instantaneous current. The built-in very good power supply system is the basis of its good sound.

Programmable analog potentiometer volume control solves left and right imbalance and digital loss

Lossless analog volume adjustment ensures good sound quality at low volume: the adjustment range is wide, the adjustment process is very thin, and the left and right channels are almost completely balanced, thus achieving a wide range of precise control of the volume.

The pursuit of good sound is also reflected in every detail, QA390 uses the PGA2311UA with higher price and lower distortion rate instead of PGA2311U.