Review: NwAvGuy's O2 DIY Amplifier - Page 44

The ODA is mostly about having a larger form factor, 6.35mm jacks, things like power cords on the back rather than everything on the front, a daughterboard option for a DAC, relays to eliminate the turn on/off transients (which are already small) and offer additional headphone protection, and so on.  There's no claim about audibly improving sound quality with this version (unless you count using the DAC)--and there really shouldn't be since the down-and-dirty part of the amp is going to be the same, if I'm reading between the lines correctly.  A different PCB layout and possibly very slightly improved power supply performance, may make a small measurable improvement in overall performance.

Quote:

Originally Posted by purrin 

Is there any proof that the O2 sounds as good as discrete designs such as the Dynalo and B22? The maker is the one writing the manifesto and making these claims. I think the burden of proof is upon him. Where are the measurements that show the O2 is as "detailed" as the discrete designs?

 

That's a silly statement.  You can just as well ask where are the measurements that show the O2 is not as detailed as discrete designs?

Put it this way, if there were no audible upgrades available to the current O2 design, why would his challenge be to amps costing only up to $500 and not any amp of any value? Clearly NwAvGuy recognises there is an audible difference (even if it is slight) the higher up the ladder you go.

Quote:

Originally Posted by upstateguy 

That's a silly statement.  You can just as well ask where are the measurements that show the O2 is not as detailed as discrete designs?

Our ears - the ultimate measurement device.

EDIT: On that note - so you agree that there is no measurement that scientifically proves or indicates the O2 is as detailed as the Dynalo or B22?

Is there proof that one headphone has better separation or soundstage than another?  Wake me up when you find it.  Till then it's all in your head or most likely voodoo.

USG, I don't think I can offer you any "proof" when the whole contention was that something like imaging (for example) doesn't have metrics for it (yet).  I find it ironic that you're asking for "evidence."  

Quote:

Originally Posted by Naim.F.C 

The funny thing about this thread is that even NwAvGuy himself believes the O2 can be improved upon, and only offers his $500 prize blind test challenge with comparisons with the O2 amp vs other mid-tier amps up to $500 value only.

 

He clearly states that there are other very accomplished amps and manufacturers out there, but that they charge a hefty premium (he brings up Violectric quite often as an example of one getting it right, but still charging too much). Add to that, he is currently developing a better amp (ODA, Objective Desktop Amp) which also throws this notion that there's no difference between amps, no need for one full stop etc, clear in the water.

Err...No.

The one limited by price is for anything that measures better.  The ABX listening test is not limited by price and is to demonstrate that the O2's distortion levels have reached the point of transparency and you can't actually hear that something else has lower distortion.  The desktop version is just about ergonomics so everything isn't crammed on to one panel.

Of course its not perfect.  It could use some more power to handle those last few fringe cases.
 

Quote:

Originally Posted by purrin 

For nwaguy (or at least his more blind followers) to suggest that he is the only one (or the select all-knowing few) who designs amps using bench tests is preposterous. I've seen test equipment and 'scopes on the benches of all the well known reputable amp builders. Not only do the good builders test, but they listen.

Well he seems to have demonstrated that some people don't test their amps with much more than RMAA and an oscilloscope...

Quote:

Originally Posted by Shike 

Judging from the measurements, assuming nothing is deficient (let's see them on a bench first) then neither is going to be more accurate or inaccurate.  You're going to need proof of your claims, and saying "but I heard it" isn't enough.  If that was the case, would you immediately believe anyone that "saw a ghost"?  Equally, if they told you the problem was with your eyes or ghost catching technique would you believe them?  Furthermore, if they claimed the proof is upon you to disprove ghosts could you do it?

 

See what you're asking us to do for a moment, register it, and reconsider your position for a moment.  Considering the above, your statements are both unreasonable and dare I say illogical.

My claims are only this: I hear X. Look past meaningless canned measurements and listen for yourself.

The claims here seem to be: There is no difference between the O2 and more expensive discrete component amps such as the B22 or Dynalo based on canned measurements of just the O2. Because of this, I'm not even going to bother listening with my ears to the other amps because the canned measurements of the O2 (just the O2) are awesome.

Quote:

Originally Posted by Anaxilus 

 

The only thing we know is that we don't know everything.  We may know a lot about some things but that's not the same...

Thank you - it's almost like some forget the purpose of science is to better understand the world, not the other way around.

What's interesting is I see Jason of Schiit hanging out here.  It'd be interesting to hear his input on this.

Quote:

Originally Posted by purrin 

Is there any proof that the O2 sounds as good as discrete designs such as the Dynalo and B22? The maker is the one writing the manifesto and making these claims. I think the burden of proof is upon him. Where are the measurements that show the O2 is as "detailed" as the discrete designs?

 

How about the measurements that show that the O2's levels of distortion are a fraction of what is considered audible distortion. Do they not count? I would imagine that would make for the most detailed sounding amp possible. 

The only counter argument is ignoring the numbers and supposing that there are magical immeasurable forces at work, as others have said. 

You have to fight numbers with numbers not feelings. So until these magical forces can be somehow quantified this side of the argument is simply irrational. 

Quote:

Originally Posted by sphinxvc 

Quote:

Thank you - it's almost like some forget the purpose of science is to better understand the world, not the other way around.

 

What's interesting is I see Jason of Schiit hanging out here.  It'd be interesting to hear his input on this.

Exactly, and this was always my approach with the headphone measurements. What do I observe, or hear? How do I measure. What do I measure? How do I present or visualize the data? Do the results concur with what I observe? How do I refine the measurement and visualization process, ad. inf.

Even then, I would be the first one to acknowledge that the CSDs I crank out are very limited and only tell a part of the picture.

Quote:

Originally Posted by Negakinu 

My point exactely. Try putting three similar-ish midrange amps next to each other, wear a blindfold and let someone else mix 'em up. Try to identify them. It's a lot harder than you'd think, especially when you read all these superlative descriptions people use to describe them. 

Also play music they are unfamiliar with.

Quote:

Originally Posted by Satellite_6 

You have to fight numbers with numbers not feelings. So until these magical forces can be somehow quantified this side of the argument is simply irrational. 

 

First step is to understand what the numbers mean. As you mentioned: "fraction of audible distortion". This would indicate that we are measuring the wrong thing. Why are we measuring things that can't be heard? As I said earlier, who cares if a manufacturer says their headphone goes up to 54kHz.

So I repeat, where is the scientific data that shows the O2 sounds as transparent as the discrete designs?

Quote:

Originally Posted by Negakinu 

My point exactely. Try putting three similar-ish midrange amps next to each other, wear a blindfold and let someone else mix 'em up. Try to identify them. It's a lot harder than you'd think, especially when you read all these superlative descriptions people use to describe them. 

This I do not disagree with. Most middle-tier (meaning 90%) amps are kinda bleh, especially in terms of transparency. Unless you want to shell out over 1k USD, stick with the O2 or desktop CMOY with a good power supply.

Quote:

Originally Posted by purrin 

First step is to understand what the numbers mean. As you mentioned: "fraction of audible distortion". This would indicate that we are measuring the wrong thing. Why are we measuring things that can't be heard? As I said earlier, who care if a manufacturer says their headphone goes up to 54kHz.

 

So I repeat, where is the scientific data that shows the O2 sounds as transparent as the discrete designs?

And you measure those things (1) for comparative purposes and (2) because they indicate other things, as I mentioned before.  Any response to that?

Performance aside, what would you describe as the difference between a design that uses op amps and a discrete design?  You have RLC elements and individually nonlinear electronics components constructed from doped silicon with both, just in different configurations (circuit layouts, size).  Why would this be a distinguishing factor in sound quality?  (in amount of power or supply rails that can be handled in practice, sure)