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O2 AMP + ODAC - Page 156

post #2326 of 5248
Quote:
Originally Posted by Taowolf51 View Post
 

I just installed this on my computer as a dedicated audio device hub:

 

http://www.amazon.com/gp/product/B005ARQV6U/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1

 

I seem to notice a boost in quality coming from my ODAC in detail and dynamics, I'm not sure why, it could be my brain telling me stupid things again. I was having some issues with the ODAC and my motherboard's USB ports (major distortion after leaving it plugged in for a few hours, fixed by unplugging and replugging) and I think it may have been fixed with this hub, though it hasn't been long enough to confirm).


Its possible the small capacitor on each port is helping to stabilize the power supply, also the fact it isn't taking power through the motherboard may be helping. Either way $20 seems a good deal to add USB3 interfaces to a pc..

post #2327 of 5248
Quote:
Originally Posted by mcandmar View Post

Yes that should work, though the fact they say "linear" in the description doesn't make any sense but that was probably just Maplin.  As long as it is an AC output it will be fine.



12v is too low, you ideally want 14v or higher, in the above unit the 15v output would be ideal.

Ah yes, I remember why. Stay around with you guys, and I begin to remember things!
Edited by r010159 - 3/28/14 at 4:17pm
post #2328 of 5248

Quote:
Originally Posted by mcandmar View Post

Yes that should work, though the fact they say "linear" in the description doesn't make any sense but that was probably just Maplin.  As long as it is an AC output it will be fine.



12v is too low, you ideally want 14v or higher, in the above unit the 15v output would be ideal.

So this is the one then. I don't understand why it states 10V in the header and then goes on to describe it as variable up to 15V. Still, it's cheap enough and I've learned something today.

Many thanks guys.
post #2329 of 5248
Please, if this question demands a complicated answer then just say good night and I'll put this light out and sleep.

Why, if it is the case that as Maplin's states, most devices require DC power, the O2 needs AC power?
post #2330 of 5248
Quote:
Originally Posted by Zorrofox View Post

Please, if this question demands a complicated answer then just say good night and I'll put this light out and sleep.

Why, if it is the case that as Maplin's states, most devices require DC power, the O2 needs AC power?


Hi,

 

the amp in the O2 runs on DC too but it has its own circuitry to generate that from AC. And since this circuitry needs to generate +12V and -12V it really needs a 13.5-20V AC supply.

 

Joachim

post #2331 of 5248
Quote:
Originally Posted by Zorrofox View Post

Please, if this question demands a complicated answer then just say good night and I'll put this light out and sleep.

Why, if it is the case that as Maplin's states, most devices require DC power, the O2 needs AC power?

Certain operations need to be made on the AC to provide DC to the circuit. The is normally provided by the wall-wart. So there is a reason the designer had to do this himself inside of the unit. IMVVHO, he may be providing power to internal circuits that have different DC power requirements.

Notice the VV in the previous sentence? smily_headphones1.gif
Edited by r010159 - 3/28/14 at 4:39pm
post #2332 of 5248

In short, because the AC to DC conversion is done inside the O2.

post #2333 of 5248
Cheers again guys. I get it. I get th "vv" too, lol. I was thinking the same 😂
post #2334 of 5248
Quote:
Originally Posted by mcandmar View Post
 


Its possible the small capacitor on each port is helping to stabilize the power supply, also the fact it isn't taking power through the motherboard may be helping. Either way $20 seems a good deal to add USB3 interfaces to a pc..

 

Possibly. The USB situation on my motherboard is a mess, it was one of the earlier USB-3 boards (Gigabyte X58A-UD3R) and has a bunch of different types of USB slots (USB 3, 2, E-Sata USB, and power USB) from 2 or 3 different USB controllers. The difference isn't subtle, which is why I'm so confused.

 

The hub is pretty nice for $20, though there are some drawbacks. Reportedly, the USB 3 speeds slow down with each extra USB 3 device you plug in beyond one. Plus, if you plug anything USB 2 into it, the whole hub becomes a USB 2 hub. The manufacturer hasn't confirmed this, though. None of this is a problem for me, though, since this is a dedicated audio USB hub, and no audio gear needs USB 3.


Edited by Taowolf51 - 3/29/14 at 7:29am
post #2335 of 5248
Quote:
Originally Posted by Zorrofox View Post



So this is the one then. I don't understand why it states 10V in the header and then goes on to describe it as variable up to 15V. Still, it's cheap enough and I've learned something today.

Many thanks guys.

 

That one looks like a winner. :regular_smile :   Like macandmar says just set it on 15Vac and away you go.   The 5mm x 2.1mm tip should fit the O2.

 

The wattage rating is a little odd.  The specs say 9.6 watts which they've rounded up to 10W in the title.  At 1 amp and a power factor of 1 that would give 9.6W / 1A = 9.6Vac, which implies the current rating would drop at 15Vac.  But no problem.  They seem to think the secondary can handle 1 amp and the "wattage" rating is really a heat dissipation thing.  Since the power going into the O2 is in the form of current spikes there is plenty of transformer "cool down" time inbetween current pulses, as opposed to using the transformer for something like outdoor lighting where it would be a constant sinusoidal current waveshape.  Most likely this is just a transformer with a single winding and a variable mechanical tap on the winding, turned by that yellow voltage adjust knob.   So it really would be a 1 amp sized winding, just tapped off at different (voltage) points.

 

In other words the important thing is at least 14Vac and a secondary rating of at least 1 amp, and you have both here.  :regular_smile :   Good find!


Edited by agdr - 3/28/14 at 6:56pm
post #2336 of 5248
I haven't even got my O2 yet and I'm already changing parts, lol. I had hoped it might arrive yesterday but no such luck. Now we're into the interminable post-free weekend and looking at Monday with crossed fingers.
post #2337 of 5248
Quote:
Originally Posted by Zorrofox View Post

I haven't even got my O2 yet and I'm already changing parts, lol. I had hoped it might arrive yesterday but no such luck. Now we're into the interminable post-free weekend and looking at Monday with crossed fingers.


Just wait how it sounds stock - I'm pretty sure it will drive your phones just fine.

 

Joachim

post #2338 of 5248
Quote:
Originally Posted by jring View Post


Just wait how it sounds stock - I'm pretty sure it will drive your phones just fine.

Joachim

No worries mate. I have no intention of spending money unless it is absolutely necessary. This is why I've chosen to go with the ODAC and O2 in the first place. It's going to be hooked up to my Mac mini and two external drives so the whole thing will be relatively small and cheap, yet still providing quality sound.

Does the O2 get particularly hot in operation?
post #2339 of 5248
Houston, we have a problem.

I've just read that the ODAC doesn't play well with a USB3 output!

http://www.head-fi.org/t/690214/jds-labs-o2-odac-issue/0_20

Is this true? If so it's gonna be a real problem for me as my Mac only has USB3 outputs. Damn it, nothing's ever easy.
post #2340 of 5248
There is a God and he doesn't like me, or he has a warped sense of irony. Not 10 minutes after my last post I get email confirmation that my amp is out for delivery today!
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