|7th June 2014, 10:43 PM||#1|
Modular 3 in 1 DAC
This thread is more about my experience with 1 specific DAC I found on the market than opportunity to start new project from scratch. I didn't found any sentence about this DAC here so if there's any existing tread about the same please move it there and I will delete half of this story .
Initial plan was to find good sounding DAC capable of 24/192 through toslink for my main stereo under $200 not limited to kit or finished product.
So what this is about? simple 1 board with 3 exchangeable modules with different chip and analog output (so far 3), I know this isn't new idea but it's pretty rare to find such nicely built kit where you can swap modules within seconds (like changing opa) for less than $300 (all together).
Main board is pretty standard similar to Weiliang's and others, what is different is module which contain known chips like WM8741, PCM1794 and AK4399, in case of WM8741 in dual mode.
Some pictures of DAC for start up:
as you can see there's nothing strange and everyone might think another basic Chinese DAC, but you would be wrong.
I'm sure there's more owners of this DAC maybe not knowing there are such options as I found it by accident when I was looking for an upgrade
There are 3 optional modules you can buy, AK4399, PCM1794A and dual WM8741:
input: digital coax + toslink, USB (optional card with 10pin)
input SR: 16-24bit/44.1k, 48k, 88.2k, 96k, 176.4k, 192khz (for both digital in) USB (depended on USB card used)
Input voltage: 15-0-15 + 9-9
VR: LM317T, LM337T, LM7805 + LT1117-5V, AMS-1117-3.3V
jitter: unknown 12.288mhz oscillator
display: input selection, sample freq.
functional buttons: select inputs, mute
WM8741 is supplied with OPA2604AP
PCM1794A is supplied with 3xOPA2134PA
AK4399 don't know but pictures showing OPA2134PA
OPA is most probably depended on seller
I couldn't found anybody who has schematics so can't comment much about other details but if you ask me for something I can read from the finished board I'll try to answer.
As I mentioned I found it by accident when I was looking for an upgrade (USB module) for my 2xWM8741 version DAC so I started with WM8741 and later bought PCM1794 module, for those of you who might be interested to buy all of them please be aware there isn't module with AK4399 available separately (yet, or I couldn't find it) so if you want all of them you have to buy DAC with AK4399 module and buy remaining 2 modules separately. I missed this option so I won't be buying new DAC just because I want only missing module , instead I bough whole new DAC with 2xAK4399 for comparison.
How did it looked before an upgrade:
To be honest, this was my first Chinese dedicated DAC for stereo so won't be able to tell you how does it stands against other Chinese DACs around, but will post later how does it perform against dual AK4399 we are building up in separate thread. So, I started with 2x WM8741, already at the beginning when I first turned it on it was like night and day comparing it to everything what I had before, nice detailed sound, I can call it natural (not neutral/flat) typical BurnBrown colored sound, 3D soundstage not as wide or deep like you can expect from tubes but reasonable, than I swapped PCM1794A, sound was more forward driven, more neutral across whole spectrum but still nicely detailed, maybe even more than WM8741, at the end of the day when I switched the player off I heard some background noise and crackling coming out of speakers especially with higher volume but this will be sorted in upgrade section. Next I tried swap OPAs between the DACs and some other I had available but couldn't found anything better sounding than 2604 (so far), either it had to much trebles or mids different dynamics but never nicely balanced like 2604, AD797 in dual mode and 4 other OPAs are on the way so once tested will report my findings, I didn't spent too much time with PCM1794A as I didn't have 3 same OPAs available for trial so within next 2 weeks I should receive new batch so will spend more time with this module, anyway in general so far so good and I was pretty happy with my purchase.
due to background noise and crackling in sound I started to look for some tweaks, at the same time I wanted some light upgrade which could little bit refine the sound, first of all I found missing ground/earth cable so I install this, second was supply voltage part of the board, those blue Wishay BC 2200uf/25v had to go together with 3x noname 1500uf/16v, as you can see below, both of them were changed to 4700uf Nover audio grade and Nichicon Audio KA range, I was limited by height of the chassis that's why those types, coming and last upgrade will be golden TCXO 0.1ppm crystal oscillator (beside USB card).
There might be several other upgrades possible like tube output stage etc. but I like transistor type of sound so I'm happy with current status.
Sound after upgrade
all above + 3 whole days of burn in process and I was ready to go...
WOW, I don't know if it was due to upgrade, burn in or combination but such a clean, refined and relaxing sound I never heard before (on my gear of course), crackling and background noise gone, I couldn't believe it, for $260 I spent so far?
you can save bit more than I did by buying it through below from Taobao, they are good service provider and I had no trouble to dealing with them, of course you can buy it through other taobao agents based on your experience but I'm bit afraid you won't find it on ebay etc.
whole AK4399 DAC - Soft control display CS8416,AK4399 opa2604 DAC decoder (up CM6631A/XMOS) Item?s description with transport and fees you'll end up somewhere between $170-180
finished board - Soft control display CS8416,AK4399 DAC decoder Board (CM6631A or XMOS module available) Item?s description with transport and fees you'll end up somewhere between $110-120, maybe less, I didn't try it
2x WM8741 module - WM8741DAC????? Item?s description all together around $50
PCM1794 module - PCM1794 decoder DAC module Item?s description all together around $40
Every opinion or review about sound quality of this and that is always subjective and what I like might not be good for you, all is also depended on quality of source and output of your hardware chain so can't guarantee that you will be happy with this DAC as I'm but I may say you won't be disappointed If you buy all 3 modules times number of available OPAs or different output stages options are pretty much unlimited
Network transport - Raumfeld connector 2 (flac files stored on NAS)
Integrated Amp - Marantz PM KI pearl lite
Speakers - Focal JMlab 826W 30th anniversary edition
p.s. sorry for my English and composition of this thread, hope it wasn't too bad
p.p.s. I'm calling my DAC "Horst"
|29th July 2014, 07:26 PM||#10|
|Thread Tools||Search this Thread|
|Thread||Thread Starter||Forum||Replies||Last Post|
|Modular v/s one-board||pra3718||Chip Amps||3||22nd September 2012 02:11 PM|
|Modular dac project with micro controller and lcd||cviller||Digital Source||10||2nd January 2007 07:06 PM|
|Modular NOS DAC||dsavitsk||Digital Source||1||14th June 2006 03:31 PM|
|modular speakers||quiet||Multi-Way||3||22nd April 2006 06:18 PM|
|modular potentiometers||merlinx76||Parts||2||9th February 2005 12:27 AM|
|New To Site?||Need Help?|