Modding the DirectStream DAC MKI

It could be a cold solder joint on the bad channel. I would re-flow and add a little fresh silver solder/flux to the transformer solder pads. Also inspect the connection bars on the side of the transformer (where the magnet wire connects to the through hole post) to make sure it’s soldered correctly. Also check the XLR connection where it is soldered to the analog board.

It’s not clear what you are saying here. Are you saying the right channel output of the DS still fades (ie. the left channel of the SYSTEM fades after swap), or are you saying the right channel of the system still fades (ie. the side that is now being fed by the left channel of the DS)?

tak1313 - I swapped the right amp to left side to determine if the issue was the amp. After the swap the issue was still on the right side - surmised as DS is the issue.

Ah, OK, so it is a DS right channel problem then. You describe the problem as “fades.” Does that mean if you stop play, then restart it, does it begin at a normal volume than fades (lowers) as the playing progresses, or do you mean the right channel (from the DS) is faded at some point and is now always lower/softer?

If you stop play for awhile, and it restarts at normal volume then fades, it COULD be as jkrichards states and be a bad solder joint, or the transformer itself could be bad. Bottom line theory is that if this is what’s happening, it SOUNDS like something is heating up/increasing resistance as signal is being fed through over time. As the resistance increases, the final output of the channel recedes. This phenomenon COULD be caused by either one - or it could be caused by something else along the signal channel.

I can’t imagine the signal through the transformer is strong enough that it’s saturating the core, or you would likely hear distortion as well. I believe the Edcore (along with the original), is just a 1:1 transformer.

It’s also POSSIBLE that the winding(s) were damaged from overheating at the solder point, but that’s a slim chance if the person doing it is reasonably experienced.

You should think about returning the DSD to the tech that did the mod to get a “professional” opinion.

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After a few hours of testing going back to the Sophia mono’s and even putting a pre-amp in I will be going back to the tech who installed the Edcor’s for professional troubleshooting. Thanks all

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Smart move

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Did you get this sorted out?

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Yes, thanks for the reminder @jkrichards. There was no issue found with the Directstream, the Edcor’s, or the installation. We actually determined that the right ribbon tweeter on my Scansonic MB-5B was starting to fail and that was the cause of the problem. The MB-5B is under warranty so dealing with that now.

I have a backup pair of Scansonic MB-5’s that I moved into the main system and the Directstream is functioning perfectly. Crisis averted. Thanks everyone who chimed in.

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My Edcor 4400 transformers arrived and will be installed by a local technician. Is it easy to remove the analog board so I don’t have to transport the entire DAC?

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It’s pretty simple. The smaller digital board is on top of the analog board. Several screws on the outputs and inputs on the outside and there are two plugs to disconnect on the board. It will save you money.

Four screws on the bottom. I use a suction cup that I have to remove glass off an IMac to remove DSD l over. This Video helps. I use the suction device instead of the all thread method in this video. Good luck and you will love the Edcor upgrade!

Thanks! Looking forward to it.

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Oops I almost forgot a very important step! Don’t forget to wear a anti-static strap when working on the dac during the removal and reinstall process!

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Hey! Is there any member here I can pay to make me an internal power cable so I can run an external power supply?

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There is some good info in this thread regarding a “star quad 14 awg” power cable…think Mr. Smith said it caught his eye as a very good fit. It’s what I used, and several others. A year later, it’s still kicking butt.

I have some extra connectors and sockets. I can mail to you if you pay postage. You can source DC cables with other connectors right length then take off the end you don’t need and crimp and solder the board connector on. I am not a cable maker but did a semi DYI.

I used Ghent Gotham cable I bought and did just that.

These are the best sounding and most shielded ones ones but there are cheaper ones too on his site. The express shipping from china is fast.

https://www.ghentaudio.com/part/dc-gac4.html

If you can wait a bit, we are designing a plug and play solution that will allow you to use the internal PS or the external one. If no external PS is hooked up the unit will use the internal PS. If the external PS is hooked up then the External PS will be used. It will be automatic and also will pass the power to the analog board at the correct time during power up. This will be a card that slides in the Bridge port with the external power supply connector and LED indicator. All one needs to do is move the analog PS plug to the new board and connect the supplied cable to the analog board. Kit will include the cable with the 2 pin connectors for the external power supply and the DSD.
We make the cables out of 14AWG 2.4mm OD Silver Plated FEP Wire High Purity OFC Copper Cable.


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Hi - please forgive me if this is widely known, but who is “we”?

Thanks!

My E.E. Son and myself.