ebay:Weiliang Dual X2 AK4399 DAC with LCD

[Kastor L]

for now "Horst" sounds better (to me) than Weiliang

woman vocals so for me is most important mid/high spectrum where 2xWM8741 shine (for now).

Hi,

I'm curious what is the WM8741 x2 device?

He scored more high and low chastitiy at a high level,longer need to drive,to warm up.

Very funny comment.

Nothing spectacular..
AD797 and succesors, as well as LT1363 have better design and performance

Yes

Try LT1363, there's no better opamp for this purpose..

Yes

LT1363 is much better then LME49710..

Yes -

Personally I currently rank LT1363 at second place after LME49990, then third place OPA627, fourth place AD797.

 

[kukynas]

Hi Kastor,

http://www.diyaudio.com/forums/digital-line-level/257430-modular-3-1-dac.html I have tweaked it even more but had no time for additional burn in and comparison, hopefully over the weekend...

 

[NinoSimona]

Thanks NinoSimona.

By the way, I am planning to use a tube output for this DAC and I have an UTO (universal tube output) that I bought from diyhifisupply.com sitting in my drawer. This UTO does not have samples to connect a balanced input to single end output. Is it possible to ground the -ve ouput from AK4399 and use the +ve as Vin to the module?

Hi NinoSimona, if I connect the UTO to outputs of AK4399 after the 11K resistors, do I need to solder the 390pF between the +ve and -ve output?

Hi Sunsun22
I'm a little late, but your first question is already answered.

Your second question: The 390pF is part of the filter, if used without opamp it becomes a first order filter together with the 11k resistors. If I calculated correctly, cut-off will be at 37 kHz. Since you are using only +ve, you can make a simple filter with the two 11k resistors in parallel (=5k5) and one capacitor to ground (a 1st order low-pass filter). Calculate the capacitor to the right value for your desired cut-off frequency. It's the method vulejov proposed in this thread.

 

[NinoSimona]

Serge: which version? v.2 is in my post #179 page 18...

If you have others schémas i am interested to compare them .

Thanks
Serge

Serge:
I have first version PCB with AK4113. There are more differences then only in the circuit schematic: PCB layout. IMO grounding is much better in first version and modification of +5V analog power supply can be done easily (as I explained in my previous post). Second version grounding is one big plane for both DAC ICs digital and analog +5V. Also HF decoupling of vref pins is better: with film caps instead of SMD ceramics, so they can be easily replaced with better 1u instead of 100n.

Nice to read all the development with the discrete opamps / HDAM modules. The discrete output stage I'm using is comparable, but has the advantage of no negative feedback being used. But it has cost me a lot more than such a HDAM module, so I think you guys got some nice deal of SQ improvement for the bucks!

Regards,
Nino

 

[kukynas]

so 5 days of burn in is done, HDAM modules compared against OP01 and everything I can say is simple.............I would be repeating myself how amazing those HDAM modules are so I'll be more than happy if someone else could buy it and test it otherwise I will look like an idiot who can hear weird stuff

p.s. I'm screwing in top cover means this does not need any additional touches and I won't do any other upgrade, it's finished and I'd like to thanks to all of you who helped

 

[NinoSimona]

Cheers kukynas! I'm glad you are happy with your DAC now, those AKM DACs are amazing, aren't they? Thanks for sharing your findings with pictures and all here with us.

Nino

 

[Valeri100]

Hi Kukynas,
I am very glad for you that you are happy with sound quality and can enjoy music listening.

I am also very happy with this DAC with transformer output stage and this demotivates me to do modification of power supply part. Perhaps I will do after summer time during rainy weekends.

 

[keres]

so 5 days of burn in is done, HDAM modules compared against OP01 and everything I can say is simple.............I would be repeating myself how amazing those HDAM modules are so I'll be more than happy if someone else could buy it and test it otherwise I will look like an idiot who can hear weird stuff

p.s. I'm screwing in top cover means this does not need any additional touches and I won't do any other upgrade, it's finished and I'd like to thanks to all of you who helped

Well : I ordered the hdam, I can compare it with opa128sm that is much more expensive and thank you for the link
A friend with same akm dac from minishow tried an external xmos to coax interface and the sounds improve, seems the internal xmos interface is not so good.

 

[730user]

Hi!
I ordered the 4399 x2b. Board. Will solder. Then I'll mount housing a satellite receiver. Transformers - 3 pieces 2x9v. MSTATOR TP28. ???????? ?????????????? ??????? | ??? «???????»

 

[kukynas]

Hi Nino, yep, it's amazing, once it's properly tweaked and connected to adequate stereo.

Hi Valeri, I didn't want to tweak it more as I could make more troubles than benefits and that's why I decided to finish it

Hi keres, I do not use USB connection, I got it connected through optical toslink so can't tell you how does it sound with xmos, I'm waiting for your findings with HDAM modules, keep us posted...

 

[phase]

Has anyone played around with the 100pf caps near the opamps?
They look like either silver mica or film of some sort maybe(?)
I finally replaced some in another (Weiliang) dac that looked a lot like polystyrene, but must have been something else, or just not that good. I used some surplus wima fkp2 in their place and am very glad I did.

 

[julcat]

latest update, I made some additional upgrade with Caps as below, analog supply part has now all caps as per schematics with Nichicon KA version, top of that I change those BC aluminum esr caps with ultra low Nippon Chemicon version, I couldn't hear any audible difference, but last week I upgraded analog part with HDAM modules as visible on the picture, hard to describe it properly but it's amazing, more dynamics, more punchy bass, no harshness at all, absolutely happy man

An externally hosted image should be here but it was not working when we last tested it.

free picture upload

Hard to see in this picture

 

[kukynas]

julcat: hard to see what, modules or Caps or ?

 

[Valeri100]

Well : I ordered the hdam, I can compare it with opa128sm that is much more expensive and thank you for the link
A friend with same akm dac from minishow tried an external xmos to coax interface and the sounds improve, seems the internal xmos interface is not so good.

I use this "Plug-in" converter and can report that it works fine. Sound quality is excellent. This module gets +5V from USB of PC and has internal transformer for SPDIF signal which provides galvanic isolation. Thus it does not bring any noise from PC in the DAC board. Advantage of such kind of USB implementation vs external one that coaxial SPDIF cable is not needed in this case. Quality of SPDIF cable makes impact on sound quality because jitter can be higher in bad cables.

 

[Valeri100]

Although I am very happy with UTC transformers I also ordered those Marantz HDAM modules. I will report result of comparison as soon as I get and test it.

 

[keres]

Hi Valéry in same way I agree with you. Infact it seems don't get any advantage from High quality USB cable.
I think an advantage is possible by using in these weiliang xmos an high quality cristal oscillator. My friend use a battery powered xmos usb to coax with three high performance cristall oscillators and he is very exicted by result, more than the internal weiliang xmos. Any way I will experiment the Dxio pro3 xmos interface to see if nothing will change or not.

Inviato dal mio SM-N9005 utilizzando Tapatalk

 

[phase]

Something I found by accident, was that the discrete opamps sound better when a jumper is applied between the power pins and the cap that is supplying them.
I knew the bursons could draw more, but never thought that it would make an audible difference...
After I lifted a trace, and replaced it with some 20-22 gauge wire, I noticed that channel had a bit more bass impact, and after repeating the jumper on the other channel, it was even again.
It was only about a half inch long trace too!

 

[kukynas]

Has anyone played around with the 100pf caps near the opamps?
They look like either silver mica or film of some sort maybe(?)
I finally replaced some in another (Weiliang) dac that looked a lot like polystyrene, but must have been something else, or just not that good. I used some surplus wima fkp2 in their place and am very glad I did.

what has changed?

I didn't think these discrete opas can make such audible difference, I was nicely surprised , simply different level, at least on my set up, it might not be so much pronounced with other but should be noticeable anyway

one more remark, if you really wanna hear maximum out of it nothing less than hi-res, hi-bit rate flac/SACD, I m listening Il Divo atm and it's like live concert in my living room, freaking crazy...

last remark: I have to kick out my family for few days

 

[terranigma]

Has anyone info about how treat analog outputs of DAC in mono mode with an officially confirmed technique?

AK4399 datasheet shows an output section (page 37) for stereo mode which differs from actual values on this kit. For example, how they did decide to use 11K resistors on each legs of analog outputs whereas datasheet shows 1K5 resistors.

 

[phase]

Replacing the unknown capacitors in the feedback loop gained a large amount of clarity and depth, were nearly the last caps changed on the entire board, may have just been the weakest link possibly, but for the $2.80 that the surplus wimps cost, it was well worth it.
I can hear the ice cubes clinking in the glasses now on some of my live recordings made in clubs.

At least you know the designer played around with the arrangement instead of just duplicating the data sheet with the resistors on the dac chip.