Xmos and AK4399 in single board

[vulejov]

Opamp is not significant, filter with 560p and 220p is too violent, try 100p and 47p..

 

[keres]

Anyone with more experience....
I want try the ada4637 in this dac.
ADA4637-1BRZ requires special application condition (gain >/= 5)
Is it an opamp electrically compatible with the weiliang dac ak4399?

Inviato dal mio SM-N9005 utilizzando Tapatalk

 

[vulejov]

Whatever you do there is no happiness with opamp..

Just take output from the AK, put in series resistor of 1k, 1n capacitor as simple filter, and then coupling capacitor .. it will be better than any opamp ..

 

[vulejov]

No one responds, I'll try to rephrase my question ..

Has anyone managed to run DSD files, theoretically speaking they would have to play with no problems .. however, I was wondering if it really works ..

Please, anyone, does this DAC play DSD files?

 

[Max Martin]

I don't have any in my library but i recall testing some 5-track i downloaded and it worked but i don't remember more then that it sounded "ok" but output level was a bit low and it wasn't that "wow" feeling i had 10 yrs ago with a dedicated sacd player i had.

- I have to listen more, and find more titles with music i can listen to! Been also very busy with other modding project and have not had chance to explore dsd so much with pc/usb yet.

Sorry for a not so good answer :/

Without op-amp?? Sounds interesting! I'm not so technical as you. But I'm learning i think 😉 Can you describe more? Maybe a schematic ?

Thx

 

[vulejov]

Now after output from AK4399 you have a 8K2 resistor and 560p capacitor .. change them with 1k and 1n, after these coupling capacitor, which value depends on the impedance of the next stage..

So if you use only the output from the converter you will have R14, C1 and C2..

If you make a buffer, here is a complete scheme.. of course, whatever you do, use only one output from AK..

 

[Max Martin]

Ok. I understand. Quite simple! So other words, i can clean out my board of all components after R1, C1and C2 then?

Couplingcap, i have a tube preamp with 100k input impedance.

Questions:
Is there any negative aspect of removing op amps?
If it's better without, why is it there??

 

[vulejov]

Opamp is in output because the designer uses the scheme from datasheet..

The idea is to use a differential output from the chip without coupling capacitor.. basically, more harm than good..as unit gain amplifier is used opamp which has 140db gain falling from 10 Hz..

Negative aspect elimination of opamp can only be what you'll have half the voltage at the output.. however, better 1V working properly, than impotent 2V ...

 

[Max Martin]

Some pics i took while it was "new" in September from Minishow. Maybe interesting for somebody?

 

[Max Martin]

Now after output from AK4399 you have a 8K2 resistor and 560p capacitor .. change them with 1k and 1n, after these coupling capacitor, which value depends on the impedance of the next stage..

So if you use only the output from the converter you will have R14, C1 and C2..

If you make a buffer, here is a complete scheme.. of course, whatever you do, use only one output from AK..

So if I understand this correct i don't have any use anymore for the 2x15V? So basically there is alot of components i can skip out like the two big ELNA 8200uf and the regulators with fins an so on? So half the board is gonna be empty?

If you look in the pics you see in each upper "corner" of the ak4399 dac there is two coppertraces on each side going 45 deegres angle out two the 2x 8.2k resistors. I'm guessing here you mean i'm only gonna use on of these traces out (one each side for left n right channel?) to make this work and of course add that 1n, 1k and output cap.

 

[vulejov]

If you made ​​buffer you'll need a power supply of analogue section ..

If you want to try a direct output from AK just remove opamps, 8k2 replace with 1k, 560p with 1n, out of there take the signal from PCB over 2u coupling capacitor..

It will be more than enough to push the preamp impedance of 100k.. you can put buffer later on that line..

 

[Max Martin]

I wanna try without opamp first. Ok thx!

 

[vulejov]

In your setup buffer is not required..

 

[Max Martin]

http://media.digikey.com/pdf/Data%20Sheets/AKM%20Semiconductor%20Inc.%20PDFs/AK4399.pdf

Should i use pin 34 (left) and 22 (right?) for audio out?

 

[vulejov]

That's right.. detach from existing RCA output of opamp and solder there coupling capacitor, zero volt remains as it were.. simplest solution..

 

[Max Martin]

Thx alot my friend. If it works ok i will be removing everything after that, for example a big r-core 50va just for 2x15v duty and lots of caps n other stuff. Instead i have room for some nice coupling caps like Rike s-cap or audyn true copper hehe 🙂

I hope it works ok 🙂

 

[vulejov]

Try to understand how something works, do not be slave to audiophile nonsense .. you don't need a big transformer and capacities .. change of the concept is what you'll hear, not change the type of capacitors ..

 

[Max Martin]

Maybe there's one thing unclear for me?!

Where do i attach rca-ground? Directly to starground or?

Ok i know

 

[vulejov]

You know, I told you, RCA ground remains where it is .. whatever solution you decide to use..

 

[Max Martin]

Yes ok sorry. I missed that.