[Xoverman]

Film on foil polypropylene cap like Wima FKP or Polystyrene Foil caps
The hard part is to get 1% or better match cross all 4 caps as it affects the i/v conversion rolloff frequency

i'm talking about the active discrete OP-Amp part. Not the passive filter after that.
On my DAC stock is silver Mica.

 

[b0bb]

i'm talking about the active discrete OP-Amp part. Not the passive filter after that.
On my DAC stock is silver Mica.

That is the set of caps I am referring to, these roll of the transimpedance of the i/v at high frequencies.
It is down to preference, polystyrene gives a more rounded and mellow presentation.
Film-foil PP caps sharpen up the presentation at the expense of some smoothness.
Keep the mica caps if you like them.

Avoid the use of the Corning glass caps here, the very low loss factor requires changing the value to readjust the transient response.
Avoid metallized PP caps the loss factor increases and you have to adjust the other way.
The sonic signature can be very harsh if the above work is not done

 

[Xoverman]

That is the set of caps I am referring to, these roll of the transimpedance of the i/v at high frequencies.
It is down to preference, polystyrene gives a more rounded and mellow presentation.
Film-foil PP caps sharpen up the presentation at the expense of some smoothness.
Keep the mica caps if you like them.

Avoid the use of the Corning glass caps here, the very low loss factor requires changing the value to readjust the transient response.
Avoid metallized PP caps the loss factor increases and you have to adjust the other way.
The sonic signature can be very harsh if the above work is not done

thanks for the tip. I would have tried the glass. I ordered glass for the i/v power supply now.
have you tried wima mkp10, or Vishay MKP 1837 ?
what is LKS using at the moment ?

 

[Xoverman]

Hello everybody,
I use a singxer-SU-6 and i2s HDMI to feed the lks 004 with audio. As playback software I use foobar2000.
I just had to set-up my system neu and installed the latest USB audio class 2 driver from singxer.
In Foobar it tells me that it's a asio output device. But it only let's me select 16 or 24bit output, not 32bit.
What am I doing wrong? I know that it used to be 32bit. Singxer can handle 32bit over i2s, and LKS can handle it to.
So why doesn't the driver give me the chance to set it up. What am I doing wrong?
Thanks for your help

 

[b0bb]

have you tried wima mkp10, or Vishay MKP 1837 ?
what is LKS using at the moment ?

Both types are metallized PP get Wima FKP or FKP2 instead
Not sure what LKS is using presently

 

[ESL57]

That is the set of caps I am referring to, these roll of the transimpedance of the i/v at high frequencies.
It is down to preference, polystyrene gives a more rounded and mellow presentation.
Film-foil PP caps sharpen up the presentation at the expense of some smoothness.
Keep the mica caps if you like them.

Avoid the use of the Corning glass caps here, the very low loss factor requires changing the value to readjust the transient response.
Avoid metallized PP caps the loss factor increases and you have to adjust the other way.
The sonic signature can be very harsh if the above work is not done

To be honest. I do not know where to start measuring and verifying signals to try to isolate the problem of noise in a specific area of the circuit (perhaps filtering in stage I / V ?. I have been able to verify that they are random, they never coincide 2 times in the same place of the audio file. For me the search is complicated. If the volume is set to -127.0db (minimum) they do not disappear, PCM does not get rid of them, they are less loud but they are there, DSD the noises are more continuous and strong, only when the signal stops, the mute works and silence appears. I have tried a cd player and put it on the coax input, with the volume at -127.0db with 44.1khz audio, in play the noises (soft) are heard, calm returns in stop. I don't know, but it seems that these first units were not perfected, it is clear that the problem is not a specific input or specific files. b0bb can you come up with any idea where these noises come from high frequency interference, would you recommend me check some signal or point of the circuit ?. My fight with this dear Dac is already personal. Thanks

 

[ESL57]

Hello everybody,
I use a singxer-SU-6 and i2s HDMI to feed the lks 004 with audio. As playback software I use foobar2000.
I just had to set-up my system neu and installed the latest USB audio class 2 driver from singxer.
In Foobar it tells me that it's a asio output device. But it only let's me select 16 or 24bit output, not 32bit.
What am I doing wrong? I know that it used to be 32bit. Singxer can handle 32bit over i2s, and LKS can handle it to.
So why doesn't the driver give me the chance to set it up. What am I doing wrong?
Thanks for your help

I'd like to help you, but I don't have SU6 here. Maybe go back to the previous controller to know if they forgot something in the new one, Gustard U16 even being a weirdo, yesterday I verified that your dsd-asio driver supports 8,16,24 and 32bits, my theory is that the ES8620 usb chip was designed by Sabre just like es9038pro, maybe sonically they get along well for that, although it seems that it will soon become obsolete, it is not recommended for new audio equipment by the manufacturer itself, linux will also be a headache for anyone who tries to make it work there, Neither in the dac x26 its implementation seems to work well, it may possibly be in the future as the holy grail of something that is no longer manufactured and nobody set their eyes on it at the time.

 

[b0bb]

To be honest. I do not know where to start measuring and verifying signals to try to isolate the problem of noise in a specific area of the circuit (perhaps filtering in stage I / V ?. I have been able to verify that they are random, they never coincide 2 times in the same place of the audio file. For me the search is complicated. If the volume is set to -127.0db (minimum) they do not disappear, PCM does not get rid of them, they are less loud but they are there, DSD the noises are more continuous and strong, only when the signal stops, the mute works and silence appears. I have tried a cd player and put it on the coax input, with the volume at -127.0db with 44.1khz audio, in play the noises (soft) are heard, calm returns in stop. I don't know, but it seems that these first units were not perfected, it is clear that the problem is not a specific input or specific files. b0bb can you come up with any idea where these noises come from high frequency interference, would you recommend me check some signal or point of the circuit ?. My fight with this dear Dac is already personal. Thanks

When did the problem start happening and did the 2 LEDs near the DAC chips flash on when it happened?

 

[Xoverman]

When did the problem start happening and did the 2 LEDs near the DAC chips flash on when it happened?

What do the LED's indicat ?

 

[Xoverman]

To be honest. I do not know where to start measuring and verifying signals to try to isolate the problem of noise in a specific area of the circuit (perhaps filtering in stage I / V ?. I have been able to verify that they are random, they never coincide 2 times in the same place of the audio file. For me the search is complicated. If the volume is set to -127.0db (minimum) they do not disappear, PCM does not get rid of them, they are less loud but they are there, DSD the noises are more continuous and strong, only when the signal stops, the mute works and silence appears. I have tried a cd player and put it on the coax input, with the volume at -127.0db with 44.1khz audio, in play the noises (soft) are heard, calm returns in stop. I don't know, but it seems that these first units were not perfected, it is clear that the problem is not a specific input or specific files. b0bb can you come up with any idea where these noises come from high frequency interference, would you recommend me check some signal or point of the circuit ?. My fight with this dear Dac is already personal. Thanks

The LKS 004 has a aluminum heatsink underneath each DAC chip. Maybe one doesn't sit right?

 

[ESL57]

When did the problem start happening and did the 2 LEDs near the DAC chips flash on when it happened?

I resend 2 photos of the upper and lower part of the main board, on the back of the pcb there are many 0.1uf capacitors between the electrolytic filtering capacitors, also in my tests I installed these capacitors between some diode bridge ( just to see the effect). I have never seen the led diodes lit near the dacs. I don't think this problem happened overnight (I bought this dac from a friend who replaced it for this problem, when after time use dsd music and hear the noises). I also remember that I removed the ground from the mains socket (no improvement). My main board has no dissipation on the es9038pro to the chassis. I would like to see in later versions or revisions what changes were made (in hardware, not just in firmware).

 

[b0bb]

I resend 2 photos of the upper and lower part of the main board, on the back of the pcb there are many 0.1uf capacitors between the electrolytic filtering capacitors, also in my tests I installed these capacitors between some diode bridge ( just to see the effect). I have never seen the led diodes lit near the dacs. I don't think this problem happened overnight (I bought this dac from a friend who replaced it for this problem, when after time use dsd music and hear the noises). I also remember that I removed the ground from the mains socket (no improvement). My main board has no dissipation on the es9038pro to the chassis. I would like to see in later versions or revisions what changes were made (in hardware, not just in firmware).

Was the DAC modified in any way when you first saw the problem?
Increase the DPLL setting to its maximum to see if that helps.

If you have an oscillloscope post pictures of the output of the AS318 clock output, scope should have a bandwidth 300MHz or higher

 

[b0bb]

What do the LED's indicat ?

DPLL lock failure.

 

[AuxInput]

Both types are metallized PP get Wima FKP or FKP2 instead
Not sure what LKS is using presently

The current gen (at least from February of this year) is using 220pf WIMA MKP (metallized polypropylene) for the I/V negative feedback compensation caps. The Gen 1 LKS used Silver Mica caps here. I have not heard Gen 1, but my experience with Mica is that they over-accentuate the ultra high frequencies and give a "tizz" type of sound/effect. They are also microphonic. When I changed to film-on-foil polypropylene caps, it gave a much more natural and smoother sound.

The current gen uses cheap metallized polyester 2200pf for the output compensation caps.

b0bb recommends WIMA FKP film-on-foil caps for these positions. For anything 2200pf and under, I have always used Kemet PFR film-on-foil which are excellent. The Kemet are more expensive than the WIMA FKP, so I hedged my bets on these instead. The WIMA are likely excellent as well.

 

[ESL57]

Was the DAC modified in any way when you first saw the problem?
Increase the DPLL setting to its maximum to see if that helps.

If you have an oscillloscope post pictures of the output of the AS318 clock output, scope should have a bandwidth 300MHz or higher

Thank you b0bb for answering, saying that everything I have tried to change / test in this dac has only been to find the solution to the noises, I bought it completely original from the factory, they were not changes to improve the sound, so I was just the one I tried with it and I know all my tests without success: Shielding of transformers. interlacing of transformer cables, change of oscillator clock, replacement of the 3 LM317 regulators with low noise modules, tests with 0.1uf capacitors between filter capacitors and some diodes to try to eliminate possible high frequency signals from the AC supply . The DPLL I keep it to the maximum (15) and this does not solve anything, just saying that PCM works well in 1 without problems and DSD from 6 can be fine without unlocking, removing the display / keypad module does not solve anything, or disconnecting the grounding. Unfortunately I only have for time domain (60Mhz oscilloscope) and frequency domain (100khz FFT signal analyzer) I was a kid from the analog age of audio, without 100Mhz signals to analyze.