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Review and Measurements of Schiit Jotunheim With AK4490 DAC

Music1969

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When that PS is double isolated (plastic enclosure) this is not needed as a user cannot touch any parts that may have become electrified when the gear is connected incorrectly or developped a fault in such a way that live mains may have come in contact with a conducting enclosure.

Thank you! In the case of the above quoted:

I know that with an external SMPS, you have AC mains voltage coming in and have lower voltage DC on the output.

But is it still possible that the external plastic SMPS develops an internal fault (I imagine it would have to be bad) such that the DC plug output carries through AC mains power? And if the DC plug connects to a metal case, then this fault could lead to the metal case becoming 'live'?

Or is this prevented by design of the SMPS and never an issue?
 

Music1969

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Edit: Just read the Wiki links.

Under Class II:

"The basic requirement is that no single failure can result in dangerous voltage becoming exposed so that it might cause an electric shock and that this is achieved without relying on an earthed metal casing. "

"Insulated AC/DC power supplies (such as cell-phone chargers) are typically designated as Class II, meaning that the DC output wires are isolated from the AC input. "

So I guess this answers my questions - this kind of fault that I described in my post above, is prevented by design.
 

Jimster480

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So for less than half the price you could combine the Schiit Modi 3 with a JDS Atom, get much better performance and not have to worry about safety? Seems like an easy choice.
Or you could avoid the Modi3 with its poor USB iplementation and get a D30 or D10 around the same price...
Or even a Sgrace Dac or JDS ODAC.
Basically anything that isn't a schiit DAC so you don't have problems with their garbage implementation of the c-media usb interface.

...and end up with twice as many units on your desk. It would've been a decent product without the electrocution risk.
This unit is quite large.... you could stack two smaller units without a problem...
If you have high impedance headphones a D30+A30 is still half the price of this with much better performance.
But since the Atom is out, its kinda hard to recommend the A30 unless you just want something that matches.

If you want a single unit... you can get the DX3 Pro and call it a day.
 

LuckyLuke575

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Schiit seems to be a describing name for this brand

It was a witty joke, until the flaws in the design and performance of their products became apparent, now it's embarrassing. Based on all the things I've seen and heard here, I'd never buy a Schiit product.
 

Matias

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Schiit is slowly adding complete APx555 measurements of all their products to their website. The Jotunheim AK4490 measurements are already on the bottom of the specs page already. They look a little different than what @amirm measured, but still cleaner than their own measurements of the Jotunheim Multibit.

AK4490 x Multibit. No PS hum on their measurements.

Jot.JPG


For the amplifier alone the THD x power 32 ohms is lower than Amir's.

Jot2.JPG
 
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amirm

amirm

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AK4490 x Multibit. No PS hum on their measurements.
Without seeing a picture of the setup, you can't tell if they used isolation power supplies and such. We would need to test one ourselves to be sure.
 

Atrox

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Without seeing a picture of the setup, you can't tell if they used isolation power supplies and such. We would need to test one ourselves to be sure.
Hi! Amir do you know/remember if the delta-sigma 4490 dac module you reviewed is the 4490 G2 (gen 2) dac module or the 4490 G1 ?
 

Steve Dallas

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you can't keep attacking schiit (even if you think you aren't, THEY, the big THEY are thinking doing this is attacking), we already know the true color since the beginning, no need to look a slightly further eye in it

They are starting to make some good stuff. Products have to be tested to sort find the gems. I bought a Modi 3 and a Magni Heresy based on Amir's recommendation.
 
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