Modding the DirectStream DAC MKI

[weedeewop]

Good point.

[jkrichards]

Any questions or correspondence for me please use the other forum. I’ll be hanging out there.
Thanks!

[scotte1]

Going to miss you, Jeff…

I hope you reconsider, in time.

Cheers.

[brian.fitterman]

You dont have to leave, you can visit two forums.

[jkrichards]

I’ll pop in from time to time.
Thanks.

[jazznut]

JK, I meanwhile tried 6800 and 8200 pF with the Lundahl. Although one wouldn’t think, as it affects above and slightly under 20 kHz, it makes a big difference. 6800 pF is too much top extension/level and sounds artificial with several recordings, 8200 is a better choice brings back an always natural top end and presence region but still is a tiny bit too little open.

I think you were right when saying, 7800 pF is probably optimal, but you mentioned that this value is hard or not to find as SMD part…is this correct or do you know any that could be used?

[kcleveland123]

FYI. In case anyone decides to make this “heat sharing” mod on the PS heat sinks there’s no need to electrically isolate between heat sinks. The devices all have insulating shoulder washers and pads. I also checked that the (4) heat sinks are already electrically connected together so the aluminum plate bridge can be installed without any electrical insulation. You may wish to include a thermal pad under the plate for better heat transfer, but the #4-40 screws do not require the shoulder washers shown in your image.

Thanks for making this suggestion. I’ve just installed the nickel transformers and want to reduce the operating temperature on the 12V regulator.

Best,
Kurt

[jkrichards]

This is not the best way to do the heat sinks. That flat plate is blocking the fins.

I found this works best.

Modding the DirectStream DAC MKI

Yesterday I was wondering why the 12V regulator in my DS has run hot since I installed ether the LL1948 or the new nickel transformers. Asked my son if he had any ideas. Well it turns out that running a 1:2 transformer gives you more gain however at the cost of drawing more power (heat). Before I did this mod I could not keep my fingers on the heatsink. Now, with the heat spreader I can keep them on all day long. If you are running a 1:2 transformer with a stock power supply (no external su…

[jkrichards]

Modding the DirectStream DAC MKI

I have had several members ask how to do the VOCM mod. Here you go: I have been using these with good results. Be careful to install these in the correct way. They have a white band on one end. This is the (+) positive end. There is also a + sign however it is very hard to see. [close] [image] All the Left R6 are in parallel and all the right R6 are in parallel so I make sure I measure each one as I install them as if you create a short you would have no way to figure out which one of …

[kcleveland123]

Have added several more holes in my heat spreader. Done with mods for a while I think.

[jkrichards]

Did you get your Vocm mod finished?

[utrak1]

Hi All,

I’d like to chime in on kcleveland123’s desoldering station recommendation. I bought one and used it to successfully replace the stock transformers with the 4400s. I figured out how to easily remove the collection tube for cleaning, which people complained about. I also figured out how to use the cleaning rods to clear the collection tube when it gets blocked with solder after almost every trigger pull. After all that, I successfully replaced the stock transformers with the 4400s.

A couple of weeks ago, I decided to perform the 1:2 mod on the 4400s, which requires me to remove the transformers. The first thing that happened is that my trusty ZD-915 got clogged up and I couldn’t unblock it using the cleaning rods. To solve the problem, I purchased a 6”-1/16” drill bit and drilled it out, which works great. However, I have to do it after each trigger pull and the bit will only fit inside the largest tip (nozzle) I have, which isn’t the one I used initially. I used the medium one. After all of that, I can’t get the 4400s back out to perform the mod.

I purchased the ZD-915 for $140 because I didn’t want to spend $324 for a Hakko FR301-03/P. When the ZD-915 got clogged up and I couldn’t clear it initially, I decided to check out the 1-year warranty. There was no company contact information in the documentation sent with the product, on the Amazon web site, or on the Internet in general. I contacted Amazon and they couldn’t find the company contact info and they refused to honor the 1-year warranty. In the future, I won’t purchase a product if I can’t find any company contact info. As the old adage goes…you get what you pay for.

[billg]

If it’s like the inexpensive model I used (borrowed) it’s important to let it warm up properly, for a few minutes after it achieves the desired heat. This heats up the entire path to the collector so the solder doesn’t go solid halfway there. It pays to rtfm

[vkennedy61]

I have the Hakko. Two things: 1) Make sure it’s heated all the way, let it heat up for a few minutes; 2) When done with the extraction, move off of your work keeping the trigger pressed for a few more seconds.

Have fun!

[utrak1]

vkennedy61, thanks for the suggestions. Can you please tell me what temperature you use when you extract transformers using your Hakko?

[jkrichards]

2.5 on bottom wheel

[tarnishedears]

What’s the purpose of that blue insulating material which looks like it is being used as a separator for the heat sinks in your picture? Since you are electrically connecting the heatsinks together with the wire, insulating them from each other doesn’t make much sense to me.

[jkrichards]

If you read the post carefully it states these are heat sink material for M,2 drives. They transfer heat not insulate.

[utrak1]

Thank you very much. I assume that translates to 425 C. jkrichards 4400 1:2 mod attempt two coming up