O2 AMP + ODAC

[potkettleblack]

Hi all,
 
I'm planning on getting the 02+odac for a future hd650/600 purchase.
 
I currently own a pair of ps500e's.
 
Is the impedance of the grado's too low to be used with the 02+odac? Will there be a humming noise?
 
I'm very new to this sorry.
 
One more thing, is it best to turn my macbook volume and vlc player all the way down and let the volume on the amp/combo do the rest or vice versa?
 
Thanks in advance guys.

 

[Grave]

The O2 is basically noiseless.
 
Max out the digital volume to 100% and then carefully use the volume knob on the O2.

 

[castleofargh]

  The O2 is basically noiseless.
 
Max out the digital volume to 100% and then carefully use the volume knob on the O2.

that!
and vlc at 100%, not 200% ^_^
 
still you won't die if you fine tune your volume with say a 10db margin from your laptop. I find that laziness is more than enough rewarding compared to the potential least significant bit loss of music.

 

[potkettleblack]

Big up yourselves gentleman.
 
So 100% on both and then take it from there with the 02 volume knob - screw** fabulous 

 

[mstrmind5]

Thanks @Dark_wizzie, @castleofargh and @adydula.

 

[glunteer]

   
 
 
 
Thanks for help oryan and castle

 
-------------------------------------------------------------------------------------
 
Excuse me, but I have one more question ...

When I'm listening to music Birdy - Wings, at the beginning of the song has a distortion (0,00 to 0,27 sec), I do not know if it's my problem O2 or ODAC, or is a badly recorded music.
 
***UPDATE: I'm using this power supply with my O2, this is what is distorting the sound?
 
Broadxent AA-1675 (http://www.emtcompany.com/broadxent-aa-1675-ac-power-supply-charger-adapter/101318691.html)

I tested another power supply and got the same thing, it seems that the music is poorly recorded

 

[Solrighal]

I have the internal volume in JRiver set to 98%. This way even very hot recordings don't clip.

 

[jring]

I have the internal volume in JRiver set to 98%. This way even very hot recordings don't clip.

With ODAC/O2 100% should be fine with 0dB - and that's maximum digital out... unless you use hi gain on O2 but the 98% won't help...
 
Joachim

 

[Solrighal]

I use Voxengo's Span VST plug-in (amongst others) & on certain tracks the peaks will go over 0dB which results in clipping. Keeping the internal volume at 98% avoids this.

 

[mcandmar]

How can you go over 0db?

 

[Poladise]

  How can you go over 0db?

It wont go above, but it will clip.

 

[Poladise]

Does anyone know if the o2 will run off ac with the batteries removed?

 

[castleofargh]

I use a -2db gain margin in foobar. it's usually not needed, but even when not abusing EQ and DSPs(and I'm usually pretty careful with those not to pass 0db) I still had a very few number of mp3s that clipped if I kept everything at 0db. and it is solved as soon as I lower the volume one way or another, so it's obviously not some hardcoded clipping. 
don't ask me how it happens, but it does sometimes and the -2db gain seemed to have solved it for me.
so if Zorro had the same experience, I understand why he would avoid 100% and keep a little margin just in case.
 
but I have to say, this has nothing to do with the odac/O2.
 
I've seen this recently (no I won't buy one, I don't need one, I'm strong willed) on bechmark product page. maybe it's related, maybe it's not, maybe it's a problem with mp3gain, maybe what they talk about is nonsense. I really have no idea ^_^.

 

High Headroom DSP - with 3.5 dB "Excess" Digital Headroom

All of the digital processing in the DAC2 HGC is designed to handle signals as high as +3.5 dBFS. Most digital systems clip signals that exceed 0 dBFS. The 0 dBFS limitation seems reasonable, as 0 dBFS is the highest sinusoidal signal level that can be represented in a digital system. However, a detailed investigation of the mathematics of PCM digital systems will reveal that inter-sample peaks may reach levels slightly higher than +3 dBFS while individual samples never exceed 0 dBFS. These inter-sample overs are common in commercial releases, and are of no consequence in a PCM system until they reach an interpolation process. But, for a variety of reasons, virtually all audio D/A converters use an interpolation process. The interpolation process is absolutely necessary to achieve 24-bit state-of-the art conversion performance. Unfortunately, inter-sample overs cause clipping in most interpolators. This clipping produces distortion products that are non-harmonic and non-musical . We believe these broadband distortion products often add a harshness or false high-frequency sparkle to digital reproduction. The DAC2 HGC avoids these problems by maintaining at least 3.5 dB of headroom in the entire conversion system. We believe this added headroom is a groundbreaking improvement.

 

[Solrighal]

That's what I meant by over I guess it's expressed as under (-2dB) but you all know what I mean. Like Castle above I'd say there are very few times its an issue but I did see it once or twice so it's fixed & can't happen in future

Truth be told, I'm not sure I can actually hear the clipping, it's maybe more psychosomatic.

 

[glunteer]

Guys,
 
thanks for the help, the problem was with a RCA splitter I was using, and only a few songs that distorted, so it was hard to find.