My last headphone AKG K619 plug mod.

Here my last outdoor headphone AKG K619 need to mod because cables continuously damaged by banding – It is really ridiculous thing, how weak cable is !

img_1739_rscw It was my second time to see damaged cable, and judged to it not be necessary fix again this. So I made it to different one.

Now I need soldering iron, soldering wire, shrinkable tube and boding material to fix connector. After prepared all items then I open left side of headphone – it was easy.


Then remove all damage part of cables with soldering iron, then put new part to make AKG K619 as detachable plug.


Finish well each parts to resit from outter shock with bonding materials, then make them together as like before. Ta-da !


Now my AKG K619 detachable plug as like K545. No need to worry about changing bad cable no more. I can buy almost all headphone cables from anywhere and it works perfectly even it has mic controller or not.

Recommend do this mod if you like make your headphone going better. It doesn’t make sound going worst, just make it more comfort.


and … RIP AKG.




My favorite headphone manufactur company AKG, the part of Harman group, now gone to burried by SoonSil Electronics domination. SoonSil Electorics means ThreeStars in Korean, and it belongs to consullation with dictator’s daughter Park and her soul commander Choi Soon Sil. And ThreeStars electronics served large black moneys to them to avoid any observation from any goverment, but now they are doing absurd claiming as they are victim of this goverment, ha! What a ridiculous ?!

This is Choi soon sil
This is Choi soon sil

So many people now sens ThreeStars electronics as same name to SoonSil Electronics. Yes, all same meaning now Battery blowing, ThreeStars, SoonSil electornics.

And now this greatest company undertook Harman group for their dirty covetousness to business making transfer to Car audio market from dead battery blew wastin’ smartphone past. What an wonderful decision, hugh ?

Now AKG and Harman will taste bitterness of SoonSil electornics’ dirty worker killing political actions and learn how good products going bad for only gain for money. Congraturations ! You’ve heen sold honor, and Rest in peace my AKG brand name to the past.

RAW scale process speed at Intel AVX instruction.



My medical RAW image scale processor benchmarked for Intel AVX instruction set. It was fully reprogrammed for be affected by optimization algorithm by compiler option.

Specification of benchmark

  • CPU: Intel Core i7-6700 @ 4GHz (Skylake-S)
  • Memory: DDR4-1066 16GB (Single channel)
  • OS: Windows 7 professional 64bit


  • MinGW-W64 64bit version 4.8.0

Compiler options

  • -fomit-frame-pointer
  • -fexpensive-optimizations
  • -O3
  • -s
  • -m64
  • -march=corei7-avx

RAW image source

  • 3072×3072, 16bit grayscale X-Ray image


Benchmark rule

  • Scale each different filter for double size.



  • Nearest (box) scale : 0.597 seconds.


  • Bilinear scale : 0.597 seconds.
  • Bicubic scale : 0.693 seconds.
  • Lanzcos 3 taps : 0.884 seconds.

Specially lanzcos 3 scale took 30% more speed at under 1 second. So I looking fore more faster way how it make faster than now. And it is almost same with B-Spline filter, or sometimes B-Spline faster than lanczos3, Hmmm …

Download test console program

Topping NX2 USB DAC & AMP review


The brand name of “Topping” was not familiar for me, so I have to anguished buy it or not in about 100 times. Then I have to trip again, to mistic big land in Asia, yeah.

It took about a month while arrive package to me. Seller seems to really lazy in most of Chinese seller. Whatever it’s bee past for me, tried to having experience of this small thinny device.



  • TI PCM2704 (Blurr-Brown) Chipset.
  • 1000mAh Li-Ion internal battery, charges at 5V 2A in maximum.
  • Maximum 100 hours running time.
  • Seperated input ports : Charge and USB/OTG in micro USB (it seems to revisioned)
  • Volume control wheel (not knob)
  • Slim height

It was hard to decide before buy this one because back pannel USB ports seems legacy USB port, and it makes many different kind of issues. But my latest version NX2 was improved as micro USB port.


Both of these ports could be used in same time. NX2 automatically selecting which port be used in charge battery. USB DAC port means OTG for some Android phones. Not all devices was not worked with this DAC.


USB DAC works as USB 1.1 and output as maximum 16bit 48KHz (DVD quality in Windows) – Most of USB 1.1 device limited to bandwidth for 16bit 48KHz output. USB 2.0 handles SPD-IF for 24bit 96KHz.

It seems just an optional service function to enjoying music in anywhere even has no sound device in system or very noisy bad situation.

Sound quality

I have compared with FiiO E07K and Zhilai devices and it may not faired comparsion because it is not similar level of price and performance.


Topping NX2 has little bit cold sound in hearing with same IEM. I can not judge it is good or not, it was not better than FiiO E07K as both of DAC and AMP.

But as perfect portable AMP and DAC, maybe NX2 is the best among of mine, slim metal body is good to carry and volume wheel control gave to me more comfort experience.

Some missed features

  • Gain control
  • Bass control

Some features not able to find. NX2 has no gain control, fixed to high gain, and it may about 10~12 dB. And no bass equlizer, it means some high impedence headphone need more bass from ouput source with internal equalizer, but most of smartphone has this.

Compare with FiiO Q01, it is little bit more lower price, and more comfort to handle it, but not more nice audio quality. It is totally depends on price at audio quality, but I like to use NX2 than FiiO Q01 beacuase suitable combine with any smartphone by flat and slim shape. And Q01 volume knob make me sometimes to hurt my other devices in my carrying bag.

Topping NX2 is much comfort utility deivce for listening more powerful music from your any source even PC and laptop to smartphones. Recommend for HiFi beginer or lone music wolves.

Experience about Zhilai H8 USB DAC.


The name of “Zhilai” seems to a brand of manufacturing single audio devices in China, I could see many products in Aliexpress, Amazon and eBay.

So I have to decided have dangerous trip to Chinese den.

For 2 weeks for shipping days, and package was just simple: One USB DAC and USB cable with air protecting bag, whole thing was inside a paper box.

A short story

Actually some kinds as like these side – personal HiFi world – may seperated by which features more importants as my thought. In case of me, not cares out shape. Only importants are lower heating for metal chassis, and smooth volume knob, multiple line out for speaker and other devices, plus not for addtional power source runs only for USB bus power – because I like use self-amp powered speaker like one of old centry’s relic Creative lab’s Inspire 2.1 2400 model.


I was look for better than bundle audio on my old desktop mainboard, actually it has multiple channel outs but basically bad audio quality always gives me bad audio experience. Before buy this device, I used FiiO E07K and E01K DACs but I need more different experience. Then it eventually held on my hand.

Quality of shape

It was about 24 USD for this device.

Actually I didn’t expect nice quality for out and inside, but it was better than my thought.


Anodized to black aluminium chassis well finished and assembled to each part. Size is actually smaller than my iPhone6s and bigger than FiiO E01K. Weight is little heavy so not moves easily. Smooth volume knob is excellent to me, I love this feeling while control volume !


In back side, there’s only traditional stereo RCA audio out for passive speaker and USB input with pwered LED. USB connector is very tight, so I don’t worry it going to loose then makes bad connection while listening something.

It was really enough to powered output thru default RCA audio out and line out on front. Actually too powerful than I expected,maybe over 2V in maximum. So it was not possible to use with my old speaker friend, too big sound not I wanted, it was too loud forr me.

As USB device

Zhilai H8 detects as C-Media USB Headphone set in USB 1.1 speed. There’s not much many features to be controlled by user.


Ouput quality option only availed for two: 16bit 44KHz and 48KHz. 24bit detailed output not possible. And Windows cannot controls volume! If I have to adjust volume, it must be only possible on H8 volume knob or stop music from my desktop, or media player software down scaling.

Audio quality

It hears little bit colder than other DACs. But enough clear than my mainboard on chip audio outs. And plus, got more powerful out non-adjustable volume audio AMP.


No audio gain level. Most of DAC minimal fuction to control gain level low and high, but H8 seems always highest. I thought it may need high resistant (about 1K ohm) cable to adjust line/audio out.

Non audio volume control thru Line/Audio out. May need own contolling audio level something.


It is just better way to hear more good audio experiece than mainboard bundle. And may considered it is not kind of soundcard, no ‘line in’ and ‘mic’ port. Just made for listening music (also possible to playing game, ha !) in lowest cost about 20 USD.

I just love it to listen my musics with some headphones like AKG K550. Love it!


First contact

DREVO brand seems to new in Aliexpress, and X1 model departed to each different capacities 60GB to 480GB. They have US sales web page and produces (or distributes) to Amazon.


X1 may their first SSD products and described in Aliexpress to used HyNix MLC NANDs with SM4480EN cached with 512MB DDR memory.


Delivered well to my home, and protecting papaer box not broken any side. It may thanks to god, yeah.


Actually this packaging is really effective for protect SSD in low cost. Not much looks cheappy like previous SSD manufacturer as like King whatever.


Protecting shell color just like my old iPhone 5, space gray? Big logo put on upside and some specifications described on bottom well.




In their sales page, described MLC from Hynix, but is it really should be trusted? nay , maybe not. I have open protecting case and identified what NAND on PCB.


There’s total 8 NANDs, SM2248EN controller with 512MB DDR memory. But there’s nothing like marked SK or Hynix, just Tigo found.


Tigo ?


Tigo ??? Is this a kind of Hynix ? Nope.


Tigo is a brand of Chinease storage device manufacturer. It must be OEM or ODM by Tigo, and nobody knows what NAND type used. Just seller described as MLC, but it is not be trusted. And seller seems to lied. Liars, Chinese.

It maybe good for think about TLC or MLC, just judge to all TLC. Just hope its life not ends to fast, really.


Crystal disk information 7 could be identified all S.M.A.R.T information and its temperature really works well.


And Crystal disk mark scored as below in USB 3.0 (SS) converter. It benchmarked for maximum bandwidth of USB 3.0 well. It is really fast enough to copy anything to through even USB 3.0. Well, real SATA3 6Gbps bandwidth may reach to maximum speed as decribe as above 400MB/sec in write.

cdmark_512_64_scoreRandom access scored average 30MB/sec in write and reads are under 20MB/sec, Hmm … Yes, it must be TLC.


I was wonder its temperature not going higher while testing. Actually I put some thermal pad on controller and DDR memory  to transfer hot energy to out shell as heatsink Рand it is really effective for every SSD of mine.

Access was good enough to use for secondary system or my Steam games. Not much recommend to use as primary booting disk because TLC is like a bomb that nobody knows when it blow up. But for while or a year, or many years – if you don’t use your PC or laptop too much everyday – may OK.

But still I don’t have trust about Chinese manufacturer by their own brand names.