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Ciúnas Audio ISO DAC Teardown and Failed Review

JJB70

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Yes but I figured if the Li packs were on fire, the inverter will be dead/shutdown anyway. Apparently you need lots of water to put out Li pack fires, no dry powder or C02. I was reading about it just the other day in relation to Li cell fires on airplanes and what they do to put them out. Interesting stuff.

A few years I was involved in doing the design approval of a very large hybrid power system on behalf of a government maritime administration (my bit was the noisy up and downy things and the system integration) and I was disappointed by just how little thought the battery manufacturers had given to fire control and how little interest they took in the matter. Their attitude amounted to trust us, we know what we are doing. The fortunate thing about that sector is you can say uh huh, you're going nowhere without my signature and as things stand the only document you will be getting will have "not approved" on it.
 

RayDunzl

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"it's like electricity, no one knows how it works, it just does"

Earlier this evening I was mesmerized by this video by someone who obviously knows more about the subject presented (and mathematics thereof) than I did, and I can honestly say I didn't learn a thing from watching it attentively from start to finish.

Warning: He gives homework.
 
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Timola

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Earlier this evening I was mesmerized by this video by someone who obviously knows more about the subject presented (and mathematics thereof) than I did, and I can honestly say I didn't learn a thing from watching it attentively from start to finish.

Warning: He gives homework.

I learnt somewhere, that the math of these theories at the time of publications was only understood by a handful of people (literally). I vaguely recall even Einstein needed help with his math. That whole period around the discovery of quantum mechanics has a fascinating history, some had colorful love/sex lives too.
 
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RayDunzl

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digicidal

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Earlier this evening I was mesmerized by this video by someone who obviously knows more about the subject presented (and mathematics thereof) than I did, and I can honestly say I didn't learn a thing from watching it attentively from start to finish.

Warning: He gives homework.
o_O I feel so cognitively enfeebled after watching that through once... going to have to try again with more sleep. Favorite quote:
That's it! That's what the second derivative is... the rest is really simple from here...
Uh, nope - LIAR!!! :mad: Reminded me of how I felt back in school. I couldn't figure out how trig and analytic geometry were so easy for me but calculus seemed insurmountably difficult. I think because it stopped being as easy for me to grasp application and thus became more like the "philosophy of math" in my mind. I'm sure the amount of substances my brain was flooded with at the time weren't helping matters either. :p
 

graz_lag

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... I vaguely recall even Einstein needed help with his math. ...

6-3=6.jpeg
 

mkawa

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You don't say. You can see that he has used such cheap wire that they have oxidized already turning green!

index.php
worse, the only thing that's stopping the battery from shorting against the project box is what looks like two pieces of napkin-like tape. in fact, it already looks like the left side is electrically connected to the case.

the battery tabs for a lipoly or lifepo4 cell should be spot welded to the ends of the battery and should definitely not be wrapped around over the battery casing because of how hot the terminals get and the instability of the electrolyte if it were to leak.

i can't believe i'm saying this, because the first unit was so bad, but this is an even worse fire hazard than the pictures in the OP.
 

graz_lag

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From one of his interviews: :facepalm::facepalm::facepalm::facepalm:

(Source: https://fairhedon.com/2017/08/21/interview-john-kenny-of-ciunas-audio/)

What do you for enjoyment when not designing digital audio devices and running your business?
When I am forced to unplug my soldering iron and scope, I relax with painting. It’s similar to audio design in the way that one can get lost in doing a painting but it comes from a totally different part of the brain — the creative, intuitive part and yet the joy in a finished painting is similar to the joy in testing an intuitive design change & hearing the results.
Some paintings of mine…!


paintings.jpg


What about John Kenny designs, philosophy, business model, and customer relationships make it unique in the marketplace?
... My philosophy …

Greatest-obstacle.jpg
 

digicidal

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Just..... WOW! :oops: Even in painting he's just copying someone else... frightening. Van Gogh must be looking like an underground acrobat right now.

Although to be fair, maybe he was just working on a set of pieces for a "Faux Van Gogh Show" somewhere... in which case, it's forgivable. ;)
 

Labjr

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Just..... WOW! :oops: Even in painting he's just copying someone else... frightening. Van Gogh must be looking like an underground acrobat right now.

Although to be fair, maybe he was just working on a set of pieces for a "Faux Van Gogh Show" somewhere... in which case, it's forgivable. ;)

Probably paint-by-number. The same way he builds his DACs
 

Mnyb

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Go to homepage of these products , what I read was interesting or frightening , depending ?

The underlying design philosophy ( delusion) is the one that each chip should be powered by battery or super cap, without any regulator in between, presumably also without any fuses or any kind of current limitations .
So the jumble of wires soldered here and there is probably that, some homemade powerbus straigth from battery to ic.

Obviously no thought on what happens if a component fails ?
 

AndrovichIV

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I have no clue who this Ciunas Audio guy is or ar-T audio and have no strong opinions about either of them. I'm of course not impressed by the teardown where the inside does look messy and (according to Amir) possibly hazardous.

However what we have here in terms of measurements is none. This is a second hand unit of unkown history and handling which is not working. That's the weakness of examining second hand units - when they are broken, who knows what could have happened? any number of reasons. Now if a brand new unit turns up broken that can speak to quality of manufacture etc. Much more useful imo. It would be nice to obtain a brand new unit from the manufacturer to actually see how it performs.

It is distasteful to see clear namecalling and allegations of wrongdoing being allowed by the ar_T manufacturer against the Ciunas manufacturer on ASR.
@ar-t , calls Ciunas (another) manufacturer a cretin in his second sentence, he associates Ciunas with a cesspool, and accuses Ciunas of fraud and apparently being a clown all on the first post. Is this something that can happen now? If ASR doesn't like them, just free pass on the name calling ?

I ask that we keep the squabbles. namecalling, and whatever is happening on other forums out of this forum, please.

I do see your point regarding name calling. Regarding the lack of measurements and the provenance of this unit:

  1. Safety of the unit > performance of the unit. If the unit isn't safe to use, it's irrelevant how it may perform.
  2. The manufacturer hasn't refuted this teardown, so it's likely representative of the final product
  3. The name-calling is relevant to the review of this product, since it suggests that the manufacturer might be using IP from another one (whether, that IP may be patented or not, is a different matter
 

Thomas savage

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Shorted lithium batteries aren't much fun...
Unless your out in the cold and it's the only means to make fire.. then you will love it lol

Perhaps this is what jk was aiming for , part DAC part survival device.
 

Labjr

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Unless your out in the cold and it's the only means to make fire.. then you will love it lol

Perhaps this is what jk was aiming for , part DAC part survival device.
Yep. turns into a Chernobyl DAC!
 

captain paranoia

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Unless your out in the cold and it's the only means to make fire.. then you will love it lol

Lithium primary batteries started to be adopted for powering military manpack radios. That's quite a big battery. I did wonder what would happen if the battery took a round... You might think 'wow! I was lucky the battery took a round for me!'. Only to regret it moments later as the thing exploded like a bomb... But I'm sure someone thought about that problem...
 

Julf

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Is the Ciunas thing CE certified/marked?
 
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