[Xoverman]

I did not deviate much in the I/V section from my stock model, with the exception of bumping up the power supply filter caps (upgraded 22uf to 100uf). I had 61.8 ohm resistors and 220pf WIMA MKP's inside the I/V circuit. The 61.9 ohm Vishay VPF3 was the best and closest resistor I could find. The output compensation were 2200pf polyester (cheap). I did not have any silver mica in my Gen 2.x (as b0bb likes to call it).

I wonder why they put silver mica in the I/V conversation stage ?

 

[Forgisound]

A lot has been written here.
Can anyone specify all the LKS 004 upgrades that have improved the sound of the DAC?

 

[littlexx26]

A lot has been written here.
Can anyone specify all the LKS 004 upgrades that have improved the sound of the DAC?

the easiest and very noticeable is to change the fuse

 

[Gilberto 62]

Hello guys. Please see if any of you can shed a little light on my digital path. It turns out that recently, in a forum about dacs in my country, Spain, I commented that I always play ALL my music prior to upsampling to dsd512, as I have seen many of you do. So, I got this answer:


"...Upsampling with DSD from DSD? It is correct to perform a PCM to DSD conversion to perform a more "analog" antialiasing, in the manner of Sony's "Superbit mapping" (SBM) process, and it would also accept an oversampling from a lower PCM to a higher one, but raise the sample from a DSD file does not make any sense, especially if they are multiples, which they always are, they want to exhaust resources of a digital source...."

What do you think about this ...? Am I correct doing that upsampling of ALL my music to dsd512 ...? or am I in an absurdity ...? Many thanks to all of you. A greeting from Spain....

 

[Forgisound]

Meitner turns everything into a DSD512, if I'm not mistaken.

 

[b0bb]

Hello guys. Please see if any of you can shed a little light on my digital path. It turns out that recently, in a forum about dacs in my country, Spain, I commented that I always play ALL my music prior to upsampling to dsd512, as I have seen many of you do. So, I got this answer:


"...Upsampling with DSD from DSD? It is correct to perform a PCM to DSD conversion to perform a more "analog" antialiasing, in the manner of Sony's "Superbit mapping" (SBM) process, and it would also accept an oversampling from a lower PCM to a higher one, but raise the sample from a DSD file does not make any sense, especially if they are multiples, which they always are, they want to exhaust resources of a digital source...."

What do you think about this ...? Am I correct doing that upsampling of ALL my music to dsd512 ...? or am I in an absurdity ...? Many thanks to all of you. A greeting from Spain....

LKS 004 uses the ES9038PRO, the PCM to DSD conversion is built in, if you supply DSD input, you will bypass this conversion.
The comment you posted does not apply here.

Doing your own conversion is no guarantee of better quality, in many cases external PCM to DSD conversion (foobar, jriver etc) is slightly worse compared to the conversion done by the chip.

In order to do better than stock, look at Roon and HQplayer, not cheap but both deliver better performance if you have hardware powerful enough to do the work.

 

[Gilberto 62]

As always, thank you very much b0bb for your opinion. Well, at the moment I am with Foobar because my pc does not support the demands of HQPlayer, but soon there will be changes in my computer hardware and I will follow that path. Greetings to all ...

 

[m-i-c-k-e-y]

double post

 

[ti5002000]

Hi guys

I am thinking of replacing all the LM317 regulators for a better ones.

Is the regulated voltage for all 3 LM317 5v or there is any that supply 3.3v?

Thanks for the help

 

[AuxInput]

A lot has been written here.
Can anyone specify all the LKS 004 upgrades that have improved the sound of the DAC?

My documentation starts on page 171 of this thread, but it's all for the latest generation.

It's too bad that LKS stopped using a high current regulator for the clock. I would have liked to use an OCXO, but found that the Accusilicon was absolutely excellent.

 

[AuxInput]

Hi guys

I am thinking of replacing all the LM317 regulators for a better ones.

Is the regulated voltage for all 3 LM317 5v or there is any that supply 3.3v?

Thanks for the help

I have thought about swapping out the LM317 with the Sparkos Labs SS1117 regulators (they are their discrete versions of LM317). However, it requires some modification on the 1st and 2nd pins. The Sparkos is internally set for a specific voltage (you can choose any voltage you want when you order them). So you will have to remove both of the SMD resistors in front of the LM317's and replace only one of them with a wire (the pin 1 ground leg) so that the regulators are properly grounded. I could not tell you what each of the three LM317's regulate for. You will have to test the output pin 2 leg on each to see how each one is configured for.

I have used the Sparkos discrete versions of the LM78xx/LM79xx regulators. They are absolutely excellent!!

I tried the NewClassD discrete regulators once. I was severely dissappointed. The made the equipment sound very low res and low end junk. I was not impressed with their discrete op amps either.

 

[ti5002000]

I have thought about swapping out the LM317 with the Sparkos Labs SS1117 regulators (they are their discrete versions of LM317). However, it requires some modification on the 1st and 2nd pins. The Sparkos is internally set for a specific voltage (you can choose any voltage you want when you order them). So you will have to remove both of the SMD resistors in front of the LM317's and replace only one of them with a wire (the pin 1 ground leg) so that the regulators are properly grounded. I could not tell you what each of the three LM317's regulate for. You will have to test the output pin 2 leg on each to see how each one is configured for.

I have used the Sparkos discrete versions of the LM78xx/LM79xx regulators. They are absolutely excellent!!

I tried the NewClassD discrete regulators once. I was severely dissappointed. The made the equipment sound very low res and low end junk. I was not impressed with their discrete op amps either.

Hi

Thanks for the answer and the help

The thing is to know what fixed voltage sparkos i have to order, i have to check after the lm317 adjuster voltage resistor and you have to follow all the pcb tracing to the next pad and then check the voltage which can be hard to figure and takes some time which i don´t have much. That´s why i asked if someone had made it, in order to save me all that time.

 

[AuxInput]

The thing is to know what fixed voltage sparkos i have to order, i have to check after the lm317 adjuster voltage resistor and you have to follow all the pcb tracing to the next pad and then check the voltage which can be hard to figure and takes some time which i don´t have much. That´s why i asked if someone had made it, in order to save me all that time.

It's easy to figure out what fixed voltages you need. Just use a multi-meter and measure the voltage on pin 2 of each LM317. That is essentially "VOUT". You might want to get a set of test leads with have a pin-point end instead of a large end. You definitely don't want to accidentally create a connection between the pins of the LM317 (this would cause sparks).

When you want to replace the LM317 with the Sparkos, use the circuit diagram on this page as a reference:

https://www.circuitstoday.com/few-lm317-voltage-regulator-circuits


Both SMD resistors in front of each LM317 need to be removed. However, you need to short one of them with a straight wire to allow pin 1 of the LM317 to connect to ground. This is "R1" on that diagram. Since I haven't actually done this, I could not tell you which resistor is which on the LKS board.

 

[AuxInput]

In previous pages, somebody referenced Belleson's newer regulators. They do have an SPX17, which looks very promising and has excellent ripple rejection (better than Sparkos). That comparison graph also showed how bad the NewClassD regulators were, lol.

I have not tried the Belleson SPX. Seems like there are a couple minor differences. The Belleson SPX does not internally limit current - it will allow current to pass through up to maximum of 3A before something blows.

The Sparkos is internally limited to 1.5A even if the consuming circuit tries to use more. The Sparkos is also based on their Class A discrete opamps, so the regulator circuit runs a similar Class A type circuit.

 

[DBX1]

Hello all.

I am an LKS 004 user and would like to get the most out of this unit. After reading the pages of mods that took place starting from page 171 onwards, I was thinking of the following:

Upgrading the crystal on the main board
Adding a heatsink to the transistors on the main board (my transistors are above the board, not below) using a peice of aluminum across 4 transistors each. This will work for the front if I bend them downwards, but leaving the back in tact.
If I remove the front transistors and place them on the bottom of the board, I could leave the transistors closest to the caps in place, and bend them downwards away from the caps so that I can place an aluminum bar on them to remove heat properly.
Adding a dedicated toroidal for the usb board - what voltage amperage should I used? 6.5v/1a ? My usb card has the tape around it to not touch the main chassis
Possibly replace the 8 caps i read around the I/v stage to improve bass slam.

I think this is enough to start on making improvements. I am not sure which version of the unit I have. My revision on the display shows 18.08s. I know this is the firmware release.

Are there any other simple improvements I should try? And where would I find the board revision number should I need to communicate that here?

Also, how easy is it to desolder the throughhole components on this unit? For small holes, my experience has been that the solder does not always completely come off a component cleanly, or some gets stuck in the throughhole, making it difficult to remove the solder, to allow sthe new component into the throughhole. Any techniques you guys use? My main source of desoldering is using a solder wick.

I know B0bb and Auxinput did the most mods to their units and are the most knowledgable to comment. I am good with a soldering iron, and know electronic parts. But I am nowhere near as knowledgable in EE as they are.

Any additional comments would be most appreciated.

Thanks all.