XMOS DSD 384 kHz / 32bit USB

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F

flowerpot

Member
Joined 2012
Hi Joro,

Not sure this has been asked before. For the I2SoverUSB, pin 7 codec reset, this pin is used for the mute functions with the LME49710 filter board ?

When will this pin "mute". Will it mute during sampling rate change ? during start/stop ? reason is I want to have the mute function to remove pop/clicks during start/stop or sampling rate change for my dsd dac.

Thanks
 
N

Naqua

Member
Joined 2004
Hi,

I would like to know how to update the firmware for the USB converter.
How do i check current firmware? I suspect it's 1.58 because i was one of the first buyers.
Is it possible to do a on-board update of the memory-ic if joro supplies the image or do i ialways have to replace the memory ic with a new programmed one.

Thanks in advance.
 
vulejov

vulejov

Banned
Joined 2010
Case with old XMOS_AK4396 DAC..
For the new one must be slightly larger..
 

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N

Naqua

Member
Joined 2004
Firmware update

Thank you Vulejov for your reply.
I read that post before. Unfortunately it doesn't answer my biggest questions.

1. How do i check current firmware?
2. Is on-board reprogramming possible if Joro supplies the image? Or do i have to program a new memory ic and replace it on the board.

Maybe someone knows the answer?

Kind regards, Naqua..
 
vulejov

vulejov

Banned
Joined 2010
Working..
Results of todays listening session.. my old XMOS_AK4396 combo have LT1818 instead of LME49710, everything else is genuine.. sounds better than new XMOS_AK4490 with LME49710.. than we replaced LME4910 with LT1363 and that was winner of the day.. differences are small but clearly audible..
 

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J

judo

Member
Joined 2003
Naqua said:
2. Is on-board reprogramming possible if Joro supplies the image? Or do i have to program a new memory ic and replace it on the board.
Click to expand...

An option is Joro send you a programmed eeprom and you replace yours with it. I programmed mine yesterday (with Lyuben's help) I can write down the process but this is your risk!
1. Bought the programmer that Joro proposed, there is a tutorial about the software from a polish guy on Youtube you will find it.
2. I soldered a dip8 socket to the eeprom pins pin1,pin2,pin6,pin5 to the socket' s pin1,pin2... etc with about 10 cms very light wires. You can check the dip socket position in the programmer's socket for example measuring resistivity betwen the programmer lettered pins and it's socket pins.The dip8 sits in the programmer's socket opposite of the lever, pin1 looks to the lever.
pin1:CS
pin2:MISO
pin6:CLK
pin5:MOSI

3.Connected the ground of the programmer and the ground of the xmos board
My xmos is bult in a dac with dual psu, but I let only the xmos pin1,pin2 power(aka USB power)
4.Joro wrote me earlier I have to short two pins in the pin row near the galvanic isolator IC during programming but last time I forgot it.(These are the outermost pins in the middle)
Maybe confusing but it is easy if you look to the pictures of the programmer and the xmos board.
5. I let the software recognise the eeprom then saved it to a file. Then erased the eeprom and programmed the new firmware.

Ask the firmware from Joro!
 
vulejov

vulejov

Banned
Joined 2010
I can not hear any significant difference, but I did not expected it..
Previous DAC is Joro's AK4396 with LT1818 instead of LME49710 and 10uF MKP instead of 22uF output capacitor..
New one is 3dB louder, for someone that could be important.. it is also easier to switch opamps.. AK4490 have more digital filters, three new one are better compared with old sharp and slow..
 
A

androa76

Member
Joined 2007
I see that 1. output stage with red wimas is different than other... why? any different in sound?
Why does this dac has no 1000-2000uf on Vref lines... bass is better, also microdynamic...
Or I see bad. You have two gold vias left on both sides.
Which of 5 filters do you like most at AK4490 ?
and how does sound setting 1,2 3 influences on sound.
Thanks
 
vulejov

vulejov

Banned
Joined 2010
androa76 said:
I see that 1. output stage with red wimas is different than other... why? any different in sound?
Why does this dac has no 1000-2000uf on Vref lines... bass is better, also microdynamic...
Or I see bad. You have two gold vias left on both sides.
Which of 5 filters do you like most at AK4490 ?
and how does sound setting 1,2 3 influences on sound.
Thanks
Click to expand...

There is no significant difference in the sound with another filter..

There is green power board for analog part, and capacitors close to opamp..but there is no such opamp which needs 1000-2000uF..

SQ 1-2-3 has no influence on sound.. can not be heard or measured..

Differences between digital fillers are barely audible, but clearly measures..
 
A

androa76

Member
Joined 2007
Not opamp....Ak4490 needs 1000-2000uf on vref pins. For better thd at low frequences. See aplication note.
Try Lme49990 or ADA4898-1 for single opamp.
Use mkp 82nf-100nf on adj pin on lm317 regulator for opamps if I see it right. Less harsh sound. Maybe put 2.2-4r7 between supply and output stage on supply lines... some more things can be done if that is 317/337 board. If it is another reg. Then appologize for writeing.
 
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vulejov

vulejov

Banned
Joined 2010
androa76 said:
Not opamp....Ak4490 needs 1000-2000uf on vref pins. For better thd at low frequences. See aplication note.
Try Lme49990 or ADA4898-1 for single opamp.
Use mkp 82nf-100nf on adj pin on lm317 regulator for opamps if I see it right. Less harsh sound. Maybe put 2.2-4r7 between supply and output stage on supply lines... some more things can be done if that is 317/337 board. If it is another reg..
Click to expand...
Datasheet for AK4490, page 60, Vref 220uF..
http://www.akm.com/file.jsp?id=273638
For XMOS and AK4490 board I use Joro's PSU..
Power supply - I2S over USB Audio
This is original analog board..
http://jlsounds.com/uploads/LME49710_schematic.pdf
I dont like LME opamps sound, very blurred higher frequencies..
What is difference between ADA4898 and AD797..
 
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