ebay:Weiliang Dual X2 AK4399 DAC with LCD

[Kastor L]

I have a single AK4399 DAC designed by Weiliang and made by "minishow".

The customer service from minishow was OK, but the build quality was not very good. For example the chassis was a bit dirty which I didn't like.

I paid for several extras like dual R-core and better capacitors.

He gave me free OPA627's (the $5 Chinese kind which are not real) for the I/V, which actually sound really good and very similar to the real OPA627.

I have another AK4399 from China as well called the L4399.

I slightly prefer the L4399 in sonics.

If you're considering the 2x 4399 make sure you ask him if it's programmed to minimum phase or not. Minimum phase is the primary advantage the 4399 has to other DAC chips.

 

[kukynas]

Hi Nino,

I was wrong, it's different, later today I'll make photo of PCB from back site

DSC00921s - My Photo Gallery
Reg_schematics - My Photo Gallery

 

[Page.P]

Kastor L: there is no I/V. AKM are all Vout chips.

 

[Kastor L]

Ah ok, sorry I meant the line-out IC.

I tried fake OPA627, LT1115, LME49720, LME49990 etc.

In my rewell_tj L4399, it has LME49720 as standard, I changed it to and prefer LME49990.

 

[lomonosoff]

Someone hears the difference between a FILTER:01/02?

 

[Kastor L]

Someone hears the difference between a FILTER:01/02?

Not difficult to hear this difference, I thought?

AK4399 fast

AK4399 Min

 

[kukynas]

Hi Nino,
back side here
DSC00925s - My Photo Gallery

lomonosoff; Kastor L: I didn't hear any difference...

 

[lomonosoff]

kukynas:I, too🙁

 

[esgigt]

Dave: I'll see what happen with those Lundahl trafos once they arrive

esgigt: true, well worst case scenario I wasted 30 bucks

lomonosoff: what happened???

keres: doesn't sound bad

Wasted? Just add freqencycompensation or start another project....

 

[lomonosoff]

esgigt:What is freqencycompensation?

 

[esgigt]

The output capacitor value is raised to 470u/6.3V, for better stability. Just pick a big cap (no low ESR type, preferably audio grade) and decide for yourself. The capacitor in the adjustment circuit, across the resistor, is also raised to 100u/6.3V (or higher voltage rating). There's not much room for bigger, 220u would be even better I think. This cap influences noise performance.
Regards, NinoSimona

You're right warning for too low esr. The datasheet is more specific. Below 0.3 ohms is a no-go. But that also can be fixed, even with low esr's. Just add a small, well calculated resistor. The cap in the adjustment circuit can be low esr.

I like your solution for the design-error

 

[esgigt]

esgigt:What is freqencycompensation?

Did you download the datasheet? The opamp has two pins between a small cap has to be connected. That cap provides the frequency compensation...... this from my memory. Don't have the ds at hand.

 

[lomonosoff]

Explain the example LME49710.

 

[NinoSimona]

...I like your solution for the design-error

Thanks esgigt!

Kastor L: Please, can you explain what you mean with the 2 graphs you posted? I suppose you are talking about the sharp/slow roll-off filter option of the AK4399. And you are in favor of the one with minimum group delay, right?

 

[Valeri100]

Hi guys
I received and installed asynchronous XMOS USB module compatible for AK4399 / DAC7 / ES9018 by Weiliang. It works very good. There is very small sound improvement (sound stage) in comparison with optical SPDIF. I am going to use this USB interface because it allows upsample in Foobar2000 up to 192K as well as playback original 24/192K tracks, SACD images and DSD (only in PCM mode as was explained by Vulejov).

A few words about installation. The module doesn't fit completely in the DAC board. There are some components which do not allows insert the board completely and in 90 degree position in the DAC board. I had to change a little bit angle. The module was sent by ebay seller Minishow without any instruction and driver. I had some doubts in which way to insert the module because it did not fit in both ways. The seller quickly responded to my request and provided driver download link and described correct module position. Driver installation and configuration instruction was not corresponding 100% to the actual process. I again had some doubts but managed to install and configure it.

I like very much sound quality of this DAC with UTC A20 transformers and USB module. It is big improvement over CS4398 based DAC which I owned.

 

[lomonosoff]

Valeri100-Take a photo of your DAC with UTC A20.

 

[Valeri100]

Valeri100-Take a photo of your DAC with UTC A20.

Privet Lomonosoff,
These are 2 pictures. I will put this board in existing pre-amplifier case as soon as I finish all experiments. I am going to try good shunt regulators soon.

 

[lomonosoff]

Valeri100:How UTC A20 an opamp better?

 

[Valeri100]

Valeri100:How UTC A20 an opamp better?

I compared it only with AD797 and with these transformers the DAC sounds better than with the OPAs (bass and soundstage). However I am not sure that I got real AD797 from Minishow.
I promised to Kukynas compare sound of this DAC with UTC A20 vs cheap Monacor LTR110 transformers which have the same impedance. I will do it this evening and will report tomorrow.

 

[Valeri100]

I just finished audition of this DAC with Monacor LTR110 transformers. It sounds very good but with the UTC A20 it sounds fantastic. Only bass performance is the same. Soundstage, mids and highs are noticeable better with the UTC A20 and sound is more live and more musical. I did not make A-B test because I did not have a multi-contact switch but I could hear difference even without immediate switching.

An year ago when I tried both transformers with another CS4398 based DAC I did not hear any difference. This might be so because digital part of this DAC and internal analogue part of AK4399 chip are better than corresponding parts of CS4398 based DAC and CS4398 chip. I guess.