Alex_Nsk
Member of the Trade: aleXmod
- Joined
- Sep 8, 2009
- Posts
- 54
- Likes
- 10
Hi for every music lovers!
Some times ago I look at the market of potrable audio and unfortunatelly just can't found any DAP which suit my taste in quality and perfomance. So I plan to make a true audiophile DAP with increadible sound quality!
As a base I choose a portable enoughth cowon X5L DAP - as a hardwire it suit all my needs, and when rockboxed it could be even better (almost any losless formats, cue, etc). The sad is it's own codec sound quality...
At first I eject the HARD from my DAP, and change it to the PRETEC 32Gb CF memory (aka X5 flashmode).
Then I research and made an upgrade plate whith micro DAC/headphone amp combo, which can be installed inside the X5L instead of it's second battery and connect it to the X5 processor via I2S bus.
The plate consist of two blocks: the first is the DC_DC converters based on TI chips which converts th 3.7v of LI-battery into the +/-5v bipolar voltage; the second is the DAC/headphone amp.
For DAC chip I choose almost top of line TI delta-sigma converter - PCM1798 (could be changed to the top TI chip - PCM1794 if any want). This is a single chip stereo 127dB SN DAC whith built in digital filter. As I/U converter stages I suggest to use some great in sound quality dual operational amplifiers in SOIC (LM4562, AD8620, THS4032, LT1364, LM6172 etc)
Some could choose from this list the only one which suit them at 200% in terms of sound quality..
As HP driver I use the TI TPA6120/THS6012 chip. Dynamic, ultrafast, great in sound quality!
Of course there are a good passive elements as well - Sanyo OS-Con G capacitors in digital PSU, The Black Gate NX/Nichicon MUSE in BIAS of DAC, BLACK GATE St/Sanyo WG/Chemicon KJZ in analog PSU.
The power of HP driver is big enought to drive the 300 Ohm senn HD580/600 (it gives aprr. 48mW@300ohm & 440mW@32Ohm)
And the sound quality of digital music become just as good as it can!
Right now there is 2 workin examples of aleXmod.
Else 3 pcs is in progress till the end of september.
Stay tuned if you are interestin' !
P.S. Below is the link to the russian thread about my way (in russian of course) and some pictures...




Some times ago I look at the market of potrable audio and unfortunatelly just can't found any DAP which suit my taste in quality and perfomance. So I plan to make a true audiophile DAP with increadible sound quality!
As a base I choose a portable enoughth cowon X5L DAP - as a hardwire it suit all my needs, and when rockboxed it could be even better (almost any losless formats, cue, etc). The sad is it's own codec sound quality...
At first I eject the HARD from my DAP, and change it to the PRETEC 32Gb CF memory (aka X5 flashmode).
Then I research and made an upgrade plate whith micro DAC/headphone amp combo, which can be installed inside the X5L instead of it's second battery and connect it to the X5 processor via I2S bus.
The plate consist of two blocks: the first is the DC_DC converters based on TI chips which converts th 3.7v of LI-battery into the +/-5v bipolar voltage; the second is the DAC/headphone amp.
For DAC chip I choose almost top of line TI delta-sigma converter - PCM1798 (could be changed to the top TI chip - PCM1794 if any want). This is a single chip stereo 127dB SN DAC whith built in digital filter. As I/U converter stages I suggest to use some great in sound quality dual operational amplifiers in SOIC (LM4562, AD8620, THS4032, LT1364, LM6172 etc)
Some could choose from this list the only one which suit them at 200% in terms of sound quality..
As HP driver I use the TI TPA6120/THS6012 chip. Dynamic, ultrafast, great in sound quality!
Of course there are a good passive elements as well - Sanyo OS-Con G capacitors in digital PSU, The Black Gate NX/Nichicon MUSE in BIAS of DAC, BLACK GATE St/Sanyo WG/Chemicon KJZ in analog PSU.
The power of HP driver is big enought to drive the 300 Ohm senn HD580/600 (it gives aprr. 48mW@300ohm & 440mW@32Ohm)
And the sound quality of digital music become just as good as it can!

Right now there is 2 workin examples of aleXmod.
Else 3 pcs is in progress till the end of september.
Stay tuned if you are interestin' !
P.S. Below is the link to the russian thread about my way (in russian of course) and some pictures...