L.K.S. Audio MH-DA004 Dual ES9038PRO DAC - Van Damme's double impact?
Oct 20, 2018 at 3:15 PM Post #1,502 of 4,419
Currently I'm using an Intel Nuc (with a stock power supply) with a Daphile software on a BW01 setting without a problem.
Do you think that an Usbridge/Kali+Isolator will improve the sound quality?
In theory ... yes.

NUC is FCC Class B certified, meaning that it meets quite strict standards for RF noise and EMI emissions.

The LKS 004 inputs are extremely sensitive to RF and EMI noise, classic symptoms of the 004 under stress is the loss of bass extension, lack of dynamic punch and poor closed in sound staging.

The first step is to put the Usbridge/Kali+Isolator in a metal case, the exposed unscreened acrylic case will simply not be sufficient.

The stacked arrangement of processor, isolator and reclocker is not ideal, there needs to be RF absorber sheets in between.

It has potential if you have the time to implement it properly starting with the steps above.
 
Oct 20, 2018 at 4:52 PM Post #1,503 of 4,419
Thank you b0bb.

Do you think that an iFi iUSBpower is a similar quality power supply for an upgraded Amanero as a LT3042 board?
I've already have inductors that need to be soldered in order to power the Amanero externally...

Please take a look at an attached photo how it's build, a specification is quite impressive (Output Voltage: 5V±0.5%, Output Current: 1A, Output Noise Floor: 0.1uV)
 
Oct 20, 2018 at 4:56 PM Post #1,504 of 4,419
ifi iusbpower.jpg
The photo
 
Oct 20, 2018 at 5:13 PM Post #1,505 of 4,419
RF noise reduction mod to the Singxer SU-1. This feeds the I2S input on my 004.
The stock SU-1 was a disappointment given the hype around its performance.
Keeping RF noise in the SU-1 under control is the first step in getting it to exceed the performance of the onboard Amanero/LT3042 combo.

Fair-rite M6 over the reclock logic
3M AB5100 over the USB side.

The absorber materials chosen to match the operating frequency.

fJOLwhK7QdujR+B9feMh9Q_thumb_159 copy.jpg

On the bottom right of the picture, note that Singxer used a connector with incomplete shielding.
The exposed USB pins will radiate RF noise into the enclosure.
Picture below shows AB5100 material used to stop this.

Kapton gold tape to prevent the absorber from shorting out nearby components.

Another problem with the SU-1 is that the metal shields of the USB and HDMI connectors are joined.
This is very undesirable given the LKS 004's sensitivity to RF noise.

This is a path for unwanted RF noise to get into the LKS 004

Additional piece of AB5100 material to help mitigate this.


UNADJUSTEDNONRAW_thumb_15a.jpg
 
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Oct 20, 2018 at 5:20 PM Post #1,506 of 4,419
Thank you b0bb.

Do you think that an iFi iUSBpower is a similar quality power supply for an upgraded Amanero as a LT3042 board?
I've already have inductors that need to be soldered in order to power the Amanero externally...

Please take a look at an attached photo how it's build, a specification is quite impressive (Output Voltage: 5V±0.5%, Output Current: 1A, Output Noise Floor: 0.1uV)
Nope. I used this before the enhanced combo came out.

The modded LT3042 board outperforms this one.
I am now using the iFi to clean up the Gen V USB input on my Schiit Yggy.
 
Oct 20, 2018 at 5:58 PM Post #1,508 of 4,419
Those RF absorbing materials look really interesting, does it make any sense to adhesive such materials to the LKS 004's chassis?
Yes. I estimate a budget of $200-300USD to fully cover the LKS.

The little piece of Fair-rite M6 is about $18 USD, a sheet of AB5100S is $75-100USD at places like Digikey and Mouser
 
Oct 21, 2018 at 2:58 AM Post #1,510 of 4,419
b0bb,
could you please share your ideas on modding the LKS 004?

I see that you have many new conceptions when comparing to your vision of LKS 003's mod.

Most of the ideas on the 003 can transfer over to the 004

1) OCXO for master clock
2) Vishay Z-foil metal foil I/V conversion resistor
3) Schottky diodes for digital and analog sections
4) Fast LDO regulators (TPS7A47, LT3042) for the digital sections
5) Tantalum caps for Vcom bypass
6) Nichicon FP caps for the clock and 9038 digital supply bypass
7) Polystyrene caps for the final stage analog filter
8) CGW glass caps for the analog bypass caps

Couple of new items not available during the 003's time

Vishay Z-foils are now available in SMD custom made values from Texas Components, I will probably rebuild the discrete opamps in the LKS with these.

Similarly the LT3042/3045 is available as a semi discrete package to replace the LM317s

Silicon Carbide (SiC) schottky, these are even quieter than the regular Si ones

Bigger OSCONS up to 2200uF 16V for the USB interface power supply.
 
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Oct 21, 2018 at 6:41 AM Post #1,512 of 4,419
Can someone explain this? Happens every time I try to play native DSD. Source is Roon, same thing when using Jriver and other DSD albums. No problems with DoP or PCM at all, though.
 
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Oct 21, 2018 at 11:40 PM Post #1,513 of 4,419
3)Panasonic OSCON polymer main filter caps. These are the older 1000uF caps, these were the biggest available at the time I built this , original value 2200uF is now available
b0bb,

The LT3042 PSU just arrived. I'm going to run it a while as is to make sure its OK.

1000uF is the highest value in the 16V SEPF catagory that you recommended for the LT3042 PSU mod. Which 2200uF cap did you have in mind?

Thanks.
 
Oct 22, 2018 at 5:16 AM Post #1,514 of 4,419
LKS uses the 9038 in asynch reclock mode, this makes it insensitive to jitter (within reason).
The USB interface thru the ISO7640 can be run at the full 384kHz PCM rate at the lowest PLL bandwidth setting without losing lock.

Allo makes good stuff, as you need a Raspberry Pi or Sparky to run the Digione board, I think the better option is to get the Kali Reclocker + Isolator boards and use the I2S input on the DAC instead.

If you can keep the RF noise under control, the I2S input will outperform the SPDIF input at a given sample rate on the LKS 004.

b0bb,

Do you happen to know which of the i2S HDMI output modules that are compatible with the Kali Reclocker is the best match for the LKS 004?
 
Oct 22, 2018 at 7:25 AM Post #1,515 of 4,419
IMG-20181022-WA0019.jpg

wow unbelievable!!!. since my lks004 is a very special verion (upgraded usb board without power suppply). the usb board draws power from the port. that means i can use whatever power supply i like. and that's it. using it to power micro iusb3.0. the results are astonishing!!!
 

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