[Xoverman]

A nother experiment that really had more impact than expected, was dampening the power supply capacitors with Blu-Tack.
I made both modifications without moving the DAC from its physical place. Didn't touch the cable's. Everything stayed in place.
That way an A / B comparison was very easy an reliable.

 

[b0bb]

The wet tantalum caps will benefit from vibration damping
Hot-melt glue used has the consistency of rubber at the DAC operating temps
Heatshrink band acts like a rubber band around the cap at high temps.

Both methods take a lot of vibration energy out of the cap

 

[b0bb]

Another example, the heatshrink bands help reduce the vibration at the base of the cap.

 

[Monolithic]

@b0bb, Did you electrically isolate the 1.3v regulators from the heatsinks? Do you happen to know the width (mm) of the heatsinks you used?

Thanks again.

 

[b0bb]

@b0bb, Did you electrically isolate the 1.3v regulators from the heatsinks? Do you happen to know the width (mm) of the heatsinks you used?

Thanks again.

I used Kapton tape, these are standard TO-220 spacing for heatsinks.

 

[rettib2001]

I’ve had the LKS 004 since the beginning of 2018.

It’s served me well and is still going strong.

I’m at a bit of a crossroads and despite not being the most active of posters, I have followed this thread from the beginning and have grown to respect the opinions voiced here.

I need a new dac. The LKS will remain in use but I have a second room where I’m finding myself doing more and more listening (speakers).

I suppose my two questions are, for those of you who have had the LKS and moved on what did you buy?

And for those who still have it, what dac on the market today in a similar price range (up to $2000) would you buy?

*Im not buying a second LKS because I want to either do away with upsampling to dsd entirely or for it to at least not be restricted by quirks in the input method: atypical i2s pin layout restricting DDC options, persistent niggles with amanero USB.

Thanks in advance for any input!

 

[leondikim]

Long overdue attention to the analog supply.

TL1431 reference, upside is dynamic impedance is 50% lower than the stock TL431 part, down side is higher noise output.

The reference is bypassed by a noise reduction cap, so the downside has less impact.
Lower dynamic impedance means a lot better bass from the 004




Mounted on the DAC

Thank you for sharing your great information. I did change four of them to LT1431 and DAC seems to work fine with the improved sound. However, a red light next to heat sinks (I circled them with yellow color) does not turn on anymore on both sides. I think I messed up the PCB holes as I desoldered the older ones. Could you help to diagnose and how to fix it?
One assumption I have is to replace with the LT1431 S8 package because I see SMD trace pads where LT1431 is installed (I highlighted with green color).

Any help would be really appreciated!

 

[b0bb]

Thank you for sharing your great information. I did change four of them to LT1431 and DAC seems to work fine with the improved sound. However, a red light next to heat sinks (I circled them with yellow color) does not turn on anymore on both sides. I think I messed up the PCB holes as I desoldered the older ones. Could you help to diagnose and how to fix it?
One assumption I have is to replace with the LT1431 S8 package because I see SMD trace pads where LT1431 is installed (I highlighted with green color).

Any help would be really appreciated!

Check the output voltage, should be between 15-16 V for the +ve and -ve rails.

Use the test points shown in the picture below.

 

[leondikim]

Check the output voltage, should be between 15-16 V for the +ve and -ve rails.

Use the test points shown in the picture below.

On the left where it was supposed to +15v, I measured 0.95v and on the right I measured 0.29v. That’s not good…

 

[leondikim]

Another unusual behavior I discovered. When I touched two of three legs with a probe, a red light turned on! FYI the voltage measured between these two legs is 22v

 

[b0bb]

Another unusual behavior I discovered. When I touched two of three legs with a probe, a red light turned on! FYI the voltage measured between these two legs is 22v

Did the output return to ±15V, if it did you might have a dry solder join somewhere.

 

[leondikim]

Did the output return to ±15V, if it did you might have a dry solder join somewhere.

I’ll try and get back you soon! Thank you!

 

[leondikim]

@b0bb it doesn’t reach up to +-15v but close to 10v when I touch that area with a probe. Also the heatsinks get warmed up as I am connect two legs with a probe

 

[Monolithic]

@leondikim - If I'm understanding correctly, you changed components A and B (circled in yellow) of the photo below to LT1431. I believe you also changed components C and D (circled in white) of the photo below to LT1431. Can you post a photo of the markings on the original components C and D?

 

[leondikim]

@leondikim - If I'm understanding correctly, you changed components A and B (circled in yellow) of the photo below to LT1431. I believe you also changed components C and D (circled in white) of the photo below to LT1431. Can you post a photo of the markings on the original components C and D?

@Monolithic, I replaced A,B, C, and D with four LT1431 each in the same orientation as the previous ones were installed.