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Ciúnas ISO-DAC USB DAC Teardown #2

Matias

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What a piece of junk. Next.
 

restorer-john

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It's definitely some corrosion related to flux residue.

I also think there's a high likelihood of much of that corrosion could also be caused by reactions with the gassing off of the battery in an enclosed box, as it is probably being "charged" at a high voltage/current with absolutely no cell condition regulation.

I've honestly never seen anything like this mess. I'm sorry, the person responsible has no business constructing, using, and especially selling such blatantly faulty, unsafe and potentially dangerous stuff.

Postal and freight companies worldwide need to be warned about accepting these products for possible air-freight.
 

Labjr

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I always thought run-of-the-mill solder had noncorrosive rosin core flux, no?
 

Labjr

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I've honestly never seen anything like this mess. I'm sorry, the person responsible has no business constructing, using, and especially selling such blatantly faulty, unsafe and potentially dangerous stuff.

Postal and freight companies worldwide need to be warned about accepting these products for possible air-freight.

I mentioned that in the other thread. That stuff should be classified and an incendiary device. It is pathetic. How the hell can anyone actually review that garbage or defend it?
 

restorer-john

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I always thought run-of-the-mill solder had noncorrosive rosin core flux, no?

Various dissimilar metals in a sealed box with chemical outgassing, along with potential difference and current flows makes for a real mess. Add to that a plumber's soldering iron and no-idea, and the result is plain to see.
 

Labjr

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Various dissimilar metals in a sealed box with chemical outgassing, along with potential difference and current flows makes for a real mess. Add to that a plumber's soldering iron and no-idea, and the result is plain to see.
I've been doing electronic service for decades and I don't usually clean my work. But I've never seen anything like that.
 

Wombat

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Corrosion. This would do it:

d7435db9-78ce-4afe-b5b0-506b2731c10a.jpg
 

restorer-john

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Blumlein 88

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You'd think through sheer repetition the soldering skills in evidence would improve.

I'd possibly think thru sheer faith he believes the spiel about how great and isolated it is. But nothing done in here looks like any attempt, even misguided has been made. Certainly not the decoupling caps he mentioned elsewhere. So about the only conclusion you can come to is the dude is a con man.

Actually this is the rare case where the hardware is so bad, and so foreign from what is claimed I don't know that he qualifies for a chance to defend his product. He could only tell you lies about it. It might be entertaining I suppose. But he won't, he knows he is a cheat.
 

tomchr

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I always thought run-of-the-mill solder had noncorrosive rosin core flux, no?
Rosin flux (RMA) is mildly hydrophilic. If you don't clean it off, you'll see larger leakage currents, which may be an issue for your circuit. It's generally considered optional to clean it, though.

No-clean flux was designed to leave minimal residue and, thus, require no cleaning.

Water-soluble flux was designed to be easy to clean (wash in 70ºC water).

For a more detailed coverage of the subject see my article on choosing solder: https://neurochrome.com/pages/choosing-solder

Tom
 

JJB70

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In a world where the audio DAC was commoditised years ago a separate DAC needs to offer either state of the art measured performance, excellent build or industrial design or esoteric functionality to have a reason to exist. Or be cheap (in the context of a DAC that appears to be $2 according to another thread).

This appears to have no special functionality, the industrial design is an after thought, measured performance mediocre and it looks like something a day one apprentice would make after being given a soldering iron for the first time and being told to just try soldering a few wires to get a feel for it. And it is a safety hazard.

To have the nerve to charge customers for such sh*t is appalling. Why on earth would you ignore all of the competently designed and manufactured alternatives (such as $9 dongles) to buy this?
 

Juhazi

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Why? The purity of sound! https://www.ciunas.biz/

A fundamental feature of the Ciunas line of products (Ciunas DAC & SPDIF) is the use of a very safe battery technology ( now supercapacitor) that allows direct powering of digital circuits. This direct power (no voltage regulator on the output), delivers the lowest noise, most stable power to digital circuits resulting in very low jitter & noise. The reported listening impressions are a stability & solidity to the soundstage.

What this means is that all the natural & subtle audio cues that are on recordings are accurately reproduced - the room ambience, the inner texture within bass, cymbal brushing, etc - the textures of sounds that we hear in real life but is so often masked or curtailed in digital audio replay. This is not the usual hyper detail associated with digital audio which is accompanied by sibilance & harshness in the highs. It is the sound of high end turntable replay & a far more captivating experience than the usual digital audio reproduction. Digital audio can often be a case of all the notes in the right place but ultimately uninteresting - these Ciúnas devices make listening to audio interesting. They reveal the life & realism, interplay & emotion, texture & room acoustic that was always on the recording but needed a pristine source to reveal. Ciúnas devices bring the audio scene alive, just like a great camera lens brings lifelike realism & detail to visual scenes.
 

FrantzM

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Perhaps my first and
last post on this device...

I would like to think that by now the designer of this device is fully aware how merciless the Internet can be. The BS may fly for a while, the turd ultimately lands with a thud. He has a public willing to gobble the notions of "texture", "air" , "PRaT" , "organic" music reproduction. Just make sure, henceforth, the products are competently designed and assembled professionally. Measurements may not change the minds of audiophiles. Shoddy, potentially dangerous product assembly such as what we're witnessing, shall hurt ... and swiftly.


Peace
 
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