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Old 4th April 2012, 04:05 PM   #2311
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I'm a bit rusty on CE marking but I believe the O2 would be exempt from EMC emissions because it has no clock oscillator(s) on board. The route with it would be to self-certify. The ODAC's another matter entirely because its a digital product so almost certainly would be subject to emissions regs if sold as a completed board.
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Old 5th April 2012, 04:07 AM   #2312
dtproff is offline dtproff  United States
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Actually I believe you are correct on the linear exemption. I was confused that this was a USB device. You think I would know better since I own the thing. Owe well, gettin old I guess.
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Old 5th April 2012, 04:08 AM   #2313
dtproff is offline dtproff  United States
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And I can't spell.
Oh well!
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Old 5th April 2012, 07:40 AM   #2314
BlueRob is offline BlueRob  Mexico
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Just as an update I tried the AD712 and even though its a higher end IC it does not sound better than the original one. I assume that is because the circuit is tuned up (brilliantly) for that specific IC. In other words if someone (not me) dares to change it will have to go through the process of revising the rest to squeeze all the juice out of a different chip.

Hats off for RS for the overall design and and clear tests done to develop this baby.
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Old 5th April 2012, 09:06 AM   #2315
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Quote:
I believe the O2 would be exempt from EMC emissions because it has no clock oscillator(s) on board.
As soon as you hook up an AC power supply, there's the potential for creating EMC emissions right there - think of it as a 50 or 60 Hz oscillator. No telling what frequencies of harmonics may be created in the circuit. This does imply that CE certification may be needed.

Quote:
The ODAC's another matter entirely because its a digital product so almost certainly would be subject to emissions regs if sold as a completed board.
I agree, don't see any way around this.
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Old 5th April 2012, 11:27 AM   #2316
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O2 review on Headfonia.

There missing bass impact and mid fulness. Missing phase shifts in the lower end? or maybe missing crosstalk at lower frequencies?

The adaptor seems powerfull enough with 16V out.

Last edited by Jelle Schrijver; 5th April 2012 at 11:46 AM.
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Old 5th April 2012, 12:34 PM   #2317
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I find the O2 itself more objective than the review. Which is quite alright.
If I were to give advice to the reviewers, I would say don't write things like, "...its transparancy [sic]. There is no coloration what so ever, it is very neutral sounding..." and follow that with, "...the bass... is missing some punch and impact. But the bass isn’t the only thing bothering me actually, there also is something bothering me with the mids . They sound a bit thin."
Or
"A good feedback from a pair of good ears to further improve the design and the tuning would definitely help." Whose ears?? And of course this implies that either a) the designer hasn't good ears, or b) he didn't listen to his own amp.
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Old 5th April 2012, 12:55 PM   #2318
gkanai is offline gkanai  Japan
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Just received my JDSL O2 and power adapter from Mouser today.

Question for O2 owners: does the unit have to be on to charge? How do we know when the batteries are fully charged?
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Old 5th April 2012, 01:05 PM   #2319
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Quote:
Originally Posted by sofaspud View Post
"A good feedback from a pair of good ears to further improve the design and the tuning would definitely help." Whose ears?? And of course this implies that either a) the designer hasn't good ears, or b) he didn't listen to his own amp.
Agree with your earlier points - the review in parts sounds self-contradictory. But yeah its most probable that a) is true - anyone who hears clear differences between components is hardly likely to be an 'objectivist' are they?

But 'hasn't good ears' is rather too simplistic - its more about paying attention to the right things, which isn't so much about ears, more about attitude.
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Old 5th April 2012, 01:07 PM   #2320
Turbon is offline Turbon  Sweden
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The O2 sound perfectly OK in my ears so I'm a happy camper.

Brgds
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