Transcending × Subversion X Limitless

LP’s new 7 series modular flagship DAP E7 debuts!

One machine infinite possibilities

Discontinued chips, no wastage dual AK4497, unleashes the full potential of the flagship DAC; Large surface area, endless possibilities the industry’s largest interchangeable module for analog PCBA area; Non-Android, very pure – a brand new LP OS with a more powerful MCU.

The new DAP is made possible by utilizing the last batch of AK4497 DACs in the world

AK4497 is a voltage-type DAC, not the current-type DAC AK4499, and therefore does not require additional I/V conversion. It is more suitable for portable DAPs. When designed properly, we can fully optimize its potential. In terms of actual performance: a portable DAP using AK4497 exceeds AK4499 based DAP in all aspects

How powerful is the DAP that fully exploits the AK4497?

Nearly 10 db higher than the current high level machines in the industry, and is 4 db higher than the nominal performance of the AK4497 DAC chip.

Simplified schematic diagram of power supply architecture for E7 AK4497 analog section

E7 AK4497 Two-Year Development Seven Major Version Circuit Evolution Simple Explanation

Over the past two years, E7’s AK4497 card circuit board has undergone dozens of fine tuning, including seven major revisions:

First revision: The THD+N limit performance of this version reached -120db, with a
dynamic range of 131db, but the sound performance did not meet our expectations
and the consistency was not stable;

Second revision: Added more DAC VREF capacitors and increased their capacity and voltage reference stability on the basis of the first edition;

Third revision: Tried different layouts and wiring to improve performance and sound, but the results were not ideal and were eventually abandoned,

Fourth revision: Adjusted the grounding of the op-amp circuit on the basis of the second edition and added an independent power supply for AK4497 AVDD5V to enhance the layering and separation of the sound;

Fifth revision: Added a pair of independent positive and negative power supplies to each op-amp on the basis of the fourth edition, which significantly improved the tension and sound field of the sound;

Sixth revision: Further optimized the layout and wiring based on the fifth edition and improved the filtering of AK4497 AVDD3.3V, Improving the performance at 12K and eliminating some noise;

Seventh revision: The final mass production version, which ultimately adopted 13 independent power supplies. On the basis of the sixth edition, copper plating was added to increase heat dissipation, reduce the impedance of the analog circuit ground, and make the sound performance more calm and atmospheric, exceeding our expected sound performance.

How is the new “LeOS” operating system different from Android?

Focus on audio, lower power consumption, less interference, easier to use! Leave more power to the decoding amplifier circuit.