[adydula]

I would go with the JDS Labs just because of their good customer service....nothing has really changed with the O2, the ODAC is a t REV B.
 
I have both and have done side by side comparisons...I dont hear any real work differences at all.
 
That said if you buying one now get the rev b it has some improvements in certain situations with USB connectivity that might benefit you, not sonically but with less probability of latency, pops, clicks etc...if you google search this you can read the details.
 
I have three rev a's and never have had any of the issues that rev b is supposed to address. Over 7 different pc's.
 
Alex

 

[Psalmanazar]

JDS Labs has the best customer service and the ODAC rev B is a totally different DAC from the original ODAC. It's USB chipset actually has ASIO drivers though. If you get separates, you might as well not get the ODAC and O2 and go with another brand or product to not deal with USB bus and battery power.

 

[Meremoth]

  JDS Labs has the best customer service and the ODAC rev B is a totally different DAC from the original ODAC. It's USB chipset actually has ASIO drivers though. If you get separates, you might as well not get the ODAC and O2 and go with another brand or product to not deal with USB bus and battery power.

Does the standalone O2 run only on battery power?  And if so, is the disadvantage with it being battery powered and not AC is that the battery powered version would have lower supply voltage, thus making the O2+ODAC combo superior in terms of maximum output power?  
 
I don't have any amps or dacs to mix and match with the O2 and ODAC anyway, so perhaps I will just get the all-in-one box instead of separate units.    

 

[adydula]

http://blog.jdslabs.com/?p=1003
 
JDS Labs has a very nice write up of the Rev B and all its stuff....
 
Alex

 

[raoultrifan]

O2 runs on both internal batteries and AC outlet as well. If used with internal batteries then indeed max. power will slightly decrease from a max. of 7V to about 5V, but you can find all the info needed on nwavguy's blog.
 
If you'll get the combo, I believe you'll loose the batteries from inside. If you'll get the "2-piece" O2 + ODAC, then you may get the battery version of O2, just in case you'll need it sometimes (I haven't really used it much, honestly).

 

[Psalmanazar]

  Does the standalone O2 run only on battery power?  And if so, is the disadvantage with it being battery powered and not AC is that the battery powered version would have lower supply voltage, thus making the O2+ODAC combo superior in terms of maximum output power?  
 
I don't have any amps or dacs to mix and match with the O2 and ODAC anyway, so perhaps I will just get the all-in-one box instead of separate units.    

No. The O2 does have issues with clipping when the battery runs out. It has issues with clipping in general due to the volume pot being between the stages. Why would you want a desktop amp that uses a battery? The O2 doesn't have that much power in general for planars. If you want enough power to drive planars and use DSPs plugins like good equalizers (The O2 isn't powerful enough to drive the HD 650 if you use Sonarworks for example), enough power to drive everything that doesn't require a speaker amp like the HE-6, look at the Schiit Magni/Modi 2 Uber stack. The Magni 2 uber is more powerful and has RCA pass throughs while the Modi 2 Uber is mains instead of USB powered and has additional non-USB inputs compared to the non-Uber ones. The O2 and ODAC aren't the best bang for buck anymore even if you build them yourself. The Schiit stack is better and cheaper while if price is your only concern and you're not driving insensitive planars, the Monoprice Desktop Amp is under a hundred bucks and comes stock with all the O2's "extra features" you have to pay more for with such as RCA pass through jacks, a full size headphone jack, and a rear AC adapter port. It's not very difficult to design a better, more powerful, and more functional amp than the O2.

Edit: Apparently yes it does have reduced output voltage on battery power according to the earlier poster above me.

 

[adydula]

"It's not very difficult to design a better, more powerful, and more functional amp than the O2."
 
Really......
 
A.

 

[HaVoC-28]

  "It's not very difficult to design a better, more powerful, and more functional amp than the O2."
 
Really......
 
A.

 
He had a bad experience (Clipping)  with O²/ODAC ... And didn't tried to know if it was a faulty unit or not,  blaming O² being a bad disign and returned it and jumped to Schiit Stack .
 
Because Clipping with an HD650 ...

unless mismatch Gain or defective unit i don't see how at safe listening levels .
 
But well the Schiit Stack is also a safe bet for a first DAC/AMP he can't go wrong with either choice , and i would have also been upset if i had a defective product ...

 

[Meremoth]

  No. The O2 does have issues with clipping when the battery runs out. It has issues with clipping in general due to the volume pot being between the stages. Why would you want a desktop amp that uses a battery? The O2 doesn't have that much power in general for planars. If you want enough power to drive planars and use DSPs plugins like good equalizers (The O2 isn't powerful enough to drive the HD 650 if you use Sonarworks for example), enough power to drive everything that doesn't require a speaker amp like the HE-6, look at the Schiit Magni/Modi 2 Uber stack. The Magni 2 uber is more powerful and has RCA pass throughs while the Modi 2 Uber is mains instead of USB powered and has additional non-USB inputs compared to the non-Uber ones. The O2 and ODAC aren't the best bang for buck anymore even if you build them yourself. The Schiit stack is better and cheaper while if price is your only concern and you're not driving insensitive planars, the Monoprice Desktop Amp is under a hundred bucks and comes stock with all the O2's "extra features" you have to pay more for with such as RCA pass through jacks, a full size headphone jack, and a rear AC adapter port. It's not very difficult to design a better, more powerful, and more functional amp than the O2.

Edit: Apparently yes it does have reduced output voltage on battery power according to the earlier poster above me.

 
The only headphones I have are the ATH-AD700's and the ATH-AD900X's, and the TH-0XX's I have ordered.  And I have no idea how to use correctly use equalizers.    
 
Is the Schiit Magni/Modi 2 Uber stack considered "neutral" sounding?  I don't currently have any external amp or DAC, so for my first amp and DAC I want something considered to be neutral sounding so I know what the headphones sound like as is instead of being colored by external devices.  Perhaps the next time I purchase an amp and dac I'll go for something more colored, but for now I just want something transparent.
 
if you consider the Schiit stack neutral while also being superior to the O2+ODAC, then perhaps I should just go for the Schiit stack?  Are there no advantages the O2+ODAC would have over the Schiit stack?  
 
If anyone else has opinions on my current O2+ODAC vs. Schiit Stack situation, please feel free to chime in, I can use all the advice I can get.  

 

[HaVoC-28]

Also Modi 2  + O² , it will work too

  . Or Modi 2 Uber if you need spdif Input . But With Modi 2 as DAC , as the max Output power is 1.5v , Gains should be something like 1.5X for low gain , and 4.5X for High Gain .

 

[Meremoth]

  Also Modi 2  + O² , it will work too

 

 
What's your opinion about the pros and cons of the Modi 2 + O2 vs. the Schiit stack vs. the O2+ODAC combo for my situation?   (I'm not worried about price)

 

[Psalmanazar]

   
He had a bad experience (Clipping)  with O²/ODAC ... And didn't tried to know if it was a faulty unit or not,  blaming O² being a bad disign and returned it and jumped to Schiit Stack .
 
Because Clipping with an HD650 ...

unless mismatch Gain or defective unit i don't see how at safe listening levels .
 
But well the Schiit Stack is also a safe bet for a first DAC/AMP he can't go wrong with either choice , and i would have also been upset if i had a defective product ...

I didn't return it. It was a problem with standard but unsupported APIs by the USB controller in the original ODAC causing the combo to stutter and clip randomly. The O2 is flawed by design in certain ways and locked by the license. It's very easy to clip if you enable DSPs outputting to the HD 600/650 even at 3.3x gain or with unmastered, quiet home recordings. No realistic listening levels of music is safe with long term exposure. Most recordings are mixed at 80-90 db spl averages. Instruments are loud and musicians are deaf.
 

   
The only headphones I have are the ATH-AD700's and the ATH-AD900X's, and the TH-0XX's I have ordered.  And I have no idea how to use correctly use equalizers.    
 
Is the Schiit Magni/Modi 2 Uber stack considered "neutral" sounding?  I don't currently have any external amp or DAC, so for my first amp and DAC I want something considered to be neutral sounding so I know what the headphones sound like as is instead of being colored by external devices.  Perhaps the next time I purchase an amp and dac I'll go for something more colored, but for now I just want something transparent.
 
if you consider the Schiit stack neutral while also being superior to the O2+ODAC, then perhaps I should just go for the Schiit stack?  Are there no advantages the O2+ODAC would have over the Schiit stack?  
 
If anyone else has opinions on my current O2+ODAC vs. Schiit Stack situation, please feel free to chime in, I can use all the advice I can get.  

The ODAC+O2 is an all in one so it's easier to transport around. It's not a good portable solution though. Nwavguy designed, measured, and christened them as "objectively neutral".

 

[HaVoC-28]

   
What's your opinion about the pros and cons of the Modi 2 + O2 vs. the Schiit stack vs. the O2+ODAC combo for my situation?  

 
O²/ODAC (separate units , always better )
 ODAC pros : output Voltage : 2.0v (same as standard redbook CD player output voltage) ,  USB auto Powered   .  Minus : More expensive or no spdif inputs .
O² :  Can run from batteries if needed , so you go anywhere with a laptop , that will power your DAC and use the O² from batteries (it don't hapens many times but ...) . ODAC + O² => Objective combo (if you like combos) .  Will drive most of the Headphones out their just fine , also adjustable Gain , for very sensitive IEMs you can use 1X gain or even 0.5X . .  Cons : Less power that Magni so maybe some rare planars may not go loud enough for some very quiet recordings depending on how loud you listen music ... but your audio technicas or coming TH 0XX will not have this problem .
For both : Objectively mesured etc ...
 
 
Schiit Stack ,  
Modi 2 pros : cheaper than the ODAC , Modi 2 Uber : Spdif Input , cons for both : 1.5 V out (but not a real problem) , no USB powered (if that matter) .
Magni 2 : Pro : more powerfull output , cons : can't run on batteries if needed .
Cool looking Combo .
Peraphs don't have all the measurements reports that the objective combo have but ...

  I didn't return it. It was a problem with standard but unsupported APIs by the USB controller in the original ODAC causing the combo to stutter and clip randomly. The O2 is flawed by design in certain ways and locked by the license. It's very easy to clip if you enable DSPs outputting to the HD 600/650 even at 3.3x gain or with unmastered, quiet home recordings. No realistic listening levels of music is safe with long term exposure. Most recordings are mixed at 80-90 db spl averages. Instruments are loud and musicians are deaf.

 
Well , i use my HD6X0 mostly on 1X gain and without any DSP effects , and don't need more than 2.5X gain for some very quiet records that i have in my collection .  The FSA Sptifire HD that i use as DAC deliver about 2.015v at max output , so for listening music with foobar on wasapi output , i can't get my HD6X0 clipp .
 
But hey , if the schiit stack does the djob for you , the better ^^ .

 

[Meremoth]

So I read a review that said he thought the modi was "neutral to lean" and that the Magni was "a good reference for a neutral amp".  So that raises the question of Magni Uber + ODAC; would that work?  
 
 
In your own personal opinions, if your only pair of headphones were the Fostex TH-0XX's (and source is Win 7 PC with realtek audio) and someone held a gun to your head and told you to pick the best choice for those headphones, would you choose Magi + ODAC, Modi + O2, Magni + Modi, or O2 + ODAC?  (all the Schiit stuff will be the "Uber" versions).
 
 
Edit:  Should I stress out about which combo is the most neutral/transparent, or are all these considered to be fairly neutral?   
 
 
TL;DR - Someone please make this decision for me.  

 

 

[castleofargh]

 

   
He had a bad experience (Clipping)  with O²/ODAC ... And didn't tried to know if it was a faulty unit or not,  blaming O² being a bad disign and returned it and jumped to Schiit Stack .
 
Because Clipping with an HD650 ...

unless mismatch Gain or defective unit i don't see how at safe listening levels .
 
But well the Schiit Stack is also a safe bet for a first DAC/AMP he can't go wrong with either choice , and i would have also been upset if i had a defective product ...

I didn't return it. It was a problem with standard but unsupported APIs by the USB controller in the original ODAC causing the combo to stutter and clip randomly. The O2 is flawed by design in certain ways and locked by the license. It's very easy to clip if you enable DSPs outputting to the HD 600/650 even at 3.3x gain or with unmastered, quiet home recordings. No realistic listening levels of music is safe with long term exposure. Most recordings are mixed at 80-90 db spl averages. Instruments are loud and musicians are deaf.

almost everybody here has been telling you odac/o2+hd650 has no problem, some of them knowing enough to build amps by themselves.
I've had one for 2 or 3years now and it's still my source of choice anytime I measure something, that's how reliable this dac/amp combo has been for me.
nwavguy actually used the hd650 as reference many times when posting about the odac/O2. for the O2 we know all about how it's made, we know the max voltage, how we should set the gain settings(if you don't, blame yourself not the amp), and many more things unavailable/unclear on other amps.  despite that, you show your massive expertise of having one problem doing something still unclear(but obviously wrong), to decide you know better than all those guys and blame the O2 for being flawed...

 
 how you go from a problem with an API to blaming an amp makes no sense whatsoever of course. the license point... IDK what to say, 99% of amps have more license locks than an O2. and et's be honest here, if what you want to do is modify an O2 for your own use, who's going to stop you? the licence is to stop people from selling crap under the name odac/O2, that's all.
 
  at one time you talked about asio when the odac has no asio driver(at least the first version), is it what you mean with API and usb controller? then DSPs, if you clip your signal because of a DSP it's100% clipped at the computer level, and 100% your own fault for not lowering the digital gain before that DSP. then you talk about gain problem in the amp... when the amp has 2 gain settings and the gain value can be changed by any noob DIYer to whatever you need. how about you stop shooting randomly trying to put some nonsense blame on this device? if you don't like the odac or the O2, don't use them. no need to lie and make up reasons.