[lorriman]

hmmmm. im enjoying the conversation going on here. im afraid i dont have enough technical knowledge or audiophile experience to contribute much, but i would like to add something nonetheless.
the creator of the O2 did say that the amp could compete with any amp under 500$. so, continuing the discussion on whether or not you can have a "better" amp for more money, going on the description of the creator, would you say that >500$ amps exist that do sound "more transparent"? excluding features, looks, build quality and things like that, just sound.

No because while there are >$500 amps that have either more power (which one or two bizzare headphones benefit by) or even lower noise/distortion performance, the latter is effectively irrelevant because the O2/ODAC performance in those terms is already at inaudible levels and will make no difference to experience let alone pleasure. So while >$500 amps and dacs might have better performance, it's academic really. The O2 has this even at high gain; so clipping the resistors to configure the minimum gain to 1x shouldn't be done for the sake of audio performance but rather because at the default 2.5x it is already too much gain for many headphones (since the volume knob has left-right audio imbalance when turned down too much) unless you turn down the source.

And logically, as you've probably guessed, it's impossible to be more transparent. I suppose one could say nearly transparent and even more nearly transparent, but since the O2 is said to be (and independent tests confirm it) actually transparent, then you can't go anywhere from there even if you do spend >$500.

So unless you need some kind of fancy feature that the O2 doesn't have, or have the HE-6 or AKG100, then the O2/ODAC is all you really need. Having said that, the magni/modi offering from Schiit is a designed-by-measurements transparent combo, and cheaper and smaller (and prettier). Being portable and having less power, there may be more headphones that combo can't power, but for many they are worth considering. If you just need an portable amp then another transparent by-measurements design is the JDS C5, which looks good indeed.

 

[autoteleology]

Also, some people ostensibly prefer a sound with lower fidelity in a certain way and might (confusingly?) define quality in some way that doesn't really relate to fidelity.

 
I've been trying to put this concept into words for ages.

 

[miceblue]

ODAC+O2+LCD-2 = heaven. Oh my gosh that was the most beautiful sound I have heard from an LCD-2. Tube amps don't do the LCD-2 justice from my experience.

 

[adydula]

miceblue I had the same setup, and the LCD2's were superb....unfortunately the LCD2's are now sold.

 
Only have my Q701's and Grados...
 
Alex

 

[adamlr]

Quote:

No because while there are >$500 amps that have either more power (which one or two bizzare headphones benefit by) or even lower noise/distortion performance, the latter is effectively irrelevant because the O2/ODAC performance in those terms is already at inaudible levels and will make no difference to experience let alone pleasure. So while >$500 amps and dacs might have better performance, it's academic really. The O2 has this even at high gain; so clipping the resistors to configure the minimum gain to 1x shouldn't be done for the sake of audio performance but rather because at the default 2.5x it is already too much gain for many headphones (since the volume knob has left-right audio imbalance when turned down too much) unless you turn down the source.

And logically, as you've probably guessed, it's impossible to be more transparent. I suppose one could say nearly transparent and even more nearly transparent, but since the O2 is said to be (and independent tests confirm it) actually transparent, then you can't go anywhere from there even if you do spend >$500.

So unless you need some kind of fancy feature that the O2 doesn't have, or have the HE-6 or AKG100, then the O2/ODAC is all you really need. Having said that, the magni/modi offering from Schiit is a designed-by-measurements transparent combo, and cheaper and smaller (and prettier). Being portable and having less power, there may be more headphones that combo can't power, but for many they are worth considering. If you just need an portable amp then another transparent by-measurements design is the JDS C5, which looks good indeed.

oh im already and O2 + Odac owner. i was just thinking out loud. thank you for your response. are you saying that ruler flat frequency responses were measured with the O2 at a reasonable, consistent volume? colour me impressed =]
 
interesting you should mention the C5, because people have reported hearing differences between the O2 and the C5, even though they are both "transparent by-measurements designs". so would they fail a blind test? or is one "closer to neutral" than the other?

 

[HamilcarBarca]

Quote:

Originally Posted by adamlr /img/forum/go_quote.gif
 
oh im already and O2 + Odac owner. i was just thinking out loud. thank you for your response. are you saying that ruler flat frequency responses were measured with the O2 at a reasonable, consistent volume? colour me impressed =]

 
In all electronic equipment, deviations from "ruler flat frequency response" are present and measurable. The deviations of O2 and ODAC were measured to be well below the level of audibility.
 

Originally Posted by adamlr /img/forum/go_quote.gif
 
interesting you should mention the C5, because people have reported hearing differences between the O2 and the C5, even though they are both "transparent by-measurements designs". so would they fail a blind test? or is one "closer to neutral" than the other?

 
 
If two amplifiers (e.g., the O2 and C5) are both neutral, then a blind test would show them to be (statistically) indistinguishable, regardless of any anecdotal observations to the contrary.

 

[adamlr]

alright. i can accept that. but what about soundstage for instance? you cant really measure things like that can you? again, im a very happy O2+Odac owner. im not questioning the gear or trying to fault it. but still, and perhaps i have fallen victim to hype and industry propaganda, do you mean to tell me that for like, 95% of all headphones, for ~300$ you get a top notch setup, unmatched by any other as far as measurements and neutrality go? that so long as youre not using power hungry monsters, the objective pair is as good as it gets, excluding things like looks and features? 
edit: im just saying i find it hard to believe is all. alot of people would consider the asgard (gasps) for arguments sake to be an upgrade. what about things like the Grace M903, or benchmark stuff?

 

[RustA]

Quote:

alright. i can accept that. but what about soundstage for instance? you cant really measure things like that can you? again, im a very happy O2+Odac owner. im not questioning the gear or trying to fault it. but still, and perhaps i have fallen victim to hype and industry propaganda, do you mean to tell me that for like, 95% of all headphones, for ~300$ you get a top notch setup, unmatched by any other as far as measurements and neutrality go? that so long as youre not using power hungry monsters, the objective pair is as good as it gets, excluding things like looks and features? 
edit: im just saying i find it hard to believe is all. alot of people would consider the asgard (gasps) for arguments sake to be an upgrade. what about things like the Grace M903, or benchmark stuff?

 
O2 and ODAC are definitely not the last word... Don't believe it. O2 is brilliant on unity gain as it is completely dead silent and offers great soundstage for the price. But it doesn't work great with high impedance headphones, at least from my experience. ODAC is no less great for the price but even my StageDAC has more detail... And if I take its crossfeed and all the different filters in consideration, Meier's DAC is in another league \(or even several leagues above) in terms of transparency.
 
Don't get me wrong, I love this Objective stuff and have owned them several times, even had more units at the same time...

 

[mikeaj]

Quote:

alright. i can accept that. but what about soundstage for instance? you cant really measure things like that can you? again, im a very happy O2+Odac owner. im not questioning the gear or trying to fault it. but still, and perhaps i have fallen victim to hype and industry propaganda, do you mean to tell me that for like, 95% of all headphones, for ~300$ you get a top notch setup, unmatched by any other as far as measurements and neutrality go? that so long as youre not using power hungry monsters, the objective pair is as good as it gets, excluding things like looks and features? 
edit: im just saying i find it hard to believe is all. alot of people would consider the asgard (gasps) for arguments sake to be an upgrade. what about things like the Grace M903, or benchmark stuff?

 
Soundstage is mostly a creation of the recording process, mix, mastering.  But for playback of any given recording, it should primarily depend on the transducers and their positioning (for a headphone, having them right next to your ears is way way way wrong, if you're listening to material mastered on and intended for playback on speakers).  Perhaps a combination of other factors: distortion, frequency and phase response, other things, also influence sound stage.  It's something that different people perceive differently, so it's hard to say.  Now, as for what people perceive, that heavily depends on what they're listening for, the state of their mind, and so on—many factors other than just the sound produced.
 
Other devices may have different features and so on, plugs, aesthetics, etc.  Some have higher power output.  How do you define an upgrade?
 
 

Spoiler: Bonus%20discussion

 
So let's suppose you're just interested in the signals produced by audio devices, as that's what influences the actual sounds being presented to you.  You could make a case that sound quality is about an entire experience and more than just the sound waves themselves, but that's a topic for another day.
 
 
So overall, O2 and ODAC both produce very good test benchmark results (except O2 channel balance, possibly).  In most categories, they are well beyond what many people (in the industry) would consider is good enough, individually, for many different measurable parameters like frequency response, noise, harmonic distortion, etc.  Some previous psychoacoustics research has been done to determine these limits.  Some people question the validity of those results.  In fact, many other audio products should exceed those levels as well.
 
As a result of that (in general), and after some people have listened for themselves, they claim that something like the O2 / ODAC are indistinguishable from ideal parts.  In general, one would expect that very small deviations are indistinguishable from the original.  The point of contention is how close is necessary, and in which ways.
 
When doing comparisons between audio devices, people often don't very carefully match volume levels; differences in volume are often mistaken for differences in sound quality, so many comparisons cannot be directly taken at face value.  Many others, even run blinded (mostly single blind), do not properly control all the nuisance variables.  There's a real lack of very good data, because it's hard to do.  As a result, people argue over this stuff incessantly, without going anywhere.
 
I don't think there's any very well-controlled demonstrations that people are sensitive to really small deviations from ideal, like the O2 and ODAC mostly accomplish.  On the other hand, there aren't many demonstrations of much in the first place.  There are many many examples of audiophiles and others who think they can tell stuff apart, not being able to when conditions are better controlled.  There are some anecdotes of people being able to, but then some guys question their methodology (with good reason? decide for yourself).

 

[adamlr]

Quote:

 
Soundstage is mostly a creation of the recording process, mix, mastering.  But for playback of any given recording, it should primarily depend on the transducers and their positioning (for a headphone, having them right next to your ears is way way way wrong, if you're listening to material mastered on and intended for playback on speakers).  Perhaps a combination of other factors: distortion, frequency and phase response, other things, also influence sound stage.  It's something that different people perceive differently, so it's hard to say.  Now, as for what people perceive, that heavily depends on what they're listening for, the state of their mind, and so on—many factors other than just the sound produced.
 
Other devices may have different features and so on, plugs, aesthetics, etc.  Some have higher power output.  How do you define an upgrade?
 
 

Spoiler: Bonus%20discussion

 
So let's suppose you're just interested in the signals produced by audio devices, as that's what influences the actual sounds being presented to you.  You could make a case that sound quality is about an entire experience and more than just the sound waves themselves, but that's a topic for another day.
 
 
So overall, O2 and ODAC both produce very good test benchmark results (except O2 channel balance, possibly).  In most categories, they are well beyond what many people (in the industry) would consider is good enough, individually, for many different measurable parameters like frequency response, noise, harmonic distortion, etc.  Some previous psychoacoustics research has been done to determine these limits.  Some people question the validity of those results.  In fact, many other audio products should exceed those levels as well.
 
As a result of that (in general), and after some people have listened for themselves, they claim that something like the O2 / ODAC are indistinguishable from ideal parts.  In general, one would expect that very small deviations are indistinguishable from the original.  The point of contention is how close is necessary, and in which ways.
 
When doing comparisons between audio devices, people often don't very carefully match volume levels; differences in volume are often mistaken for differences in sound quality, so many comparisons cannot be directly taken at face value.  Many others, even run blinded (mostly single blind), do not properly control all the nuisance variables.  There's a real lack of very good data, because it's hard to do.  As a result, people argue over this stuff incessantly, without going anywhere.
 
I don't think there's any very well-controlled demonstrations that people are sensitive to really small deviations from ideal, like the O2 and ODAC mostly accomplish.  On the other hand, there aren't many demonstrations of much in the first place.  There are many many examples of audiophiles and others who think they can tell stuff apart, not being able to when conditions are better controlled.  There are some anecdotes of people being able to, but then some guys question their methodology (with good reason? decide for yourself).

wow. urm, alright. considering all you have written, including the spoiler, i would consider an upgrade like this: noticeably audibly "more transparent" than the objective set and still being able to drive 95% of all headphones just like the O2. excluding build quality, looks, features, exotic\prestigious components. just soundwise, presenting a flat, linear response and having enough power to drive allmost all headphones, but doing so better than the O2.
in all honesty, i wasnt really considering getting any other amp anyway. but could it be that getting another amp (for the same purpose as the O2, i.e - not more portable or whatever) would simply be redundant? looks like i made the right choice of amps... somehow i still dont buy it though. maybe im too brainwashed 

 

[miceblue]

Speaking of comparing the ODAC/O2 to more expensive rigs...
 

 

[SunshineReggae]

Quote:

 
O2 and ODAC are definitely not the last word... Don't believe it. O2 is brilliant on unity gain as it is completely dead silent and offers great soundstage for the price. But it doesn't work great with high impedance headphones, at least from my experience. ODAC is no less great for the price but even my StageDAC has more detail... And if I take its crossfeed and all the different filters in consideration, Meier's DAC is in another league \(or even several leagues above) in terms of transparency.
 
Don't get me wrong, I love this Objective stuff and have owned them several times, even had more units at the same time...

This is the kind of stuff that I don't believe. I especially like the note on detail, which reeks of sighted testing. I also like where you say the Meier's DAC is superior in transparancy - while you introduce forms of distortion such as crossfeed and tweak filters.
 
Don't get me wrong, I love reading about all the devices that don't actually improve sound quality, but ultimately it's audiophile nonsense.

 

[SunshineReggae]

Quote:

alright. i can accept that. but what about soundstage for instance? you cant really measure things like that can you? again, im a very happy O2+Odac owner. im not questioning the gear or trying to fault it. but still, and perhaps i have fallen victim to hype and industry propaganda, do you mean to tell me that for like, 95% of all headphones, for ~300$ you get a top notch setup, unmatched by any other as far as measurements and neutrality go? that so long as youre not using power hungry monsters, the objective pair is as good as it gets, excluding things like looks and features? 
edit: im just saying i find it hard to believe is all. alot of people would consider the asgard (gasps) for arguments sake to be an upgrade. what about things like the Grace M903, or benchmark stuff?

Have you ever wondered *why* you believe amping should be expensive?
 
Anyway, yes if you have an amp like a fiio e9 or an O2, its really about as good as it's going to get. For some reason people still want to believe amps can "improve soundstage", make the sound "sweet", or "liquid", and all that nonsense. It's just stupid to be honest. There's really no other word for it.

 

[miceblue]

Quote:

Quote:

alright. i can accept that. but what about soundstage for instance? you cant really measure things like that can you? again, im a very happy O2+Odac owner. im not questioning the gear or trying to fault it. but still, and perhaps i have fallen victim to hype and industry propaganda, do you mean to tell me that for like, 95% of all headphones, for ~300$ you get a top notch setup, unmatched by any other as far as measurements and neutrality go? that so long as youre not using power hungry monsters, the objective pair is as good as it gets, excluding things like looks and features? 
edit: im just saying i find it hard to believe is all. alot of people would consider the asgard (gasps) for arguments sake to be an upgrade. what about things like the Grace M903, or benchmark stuff?

Have you ever wondered *why* you believe amping should be expensive?
 
Anyway, yes if you have an amp like a fiio e9 or an O2, its really about as good as it's going to get. For some reason people still want to believe amps can "improve soundstage", make the sound "sweet", or "liquid", and all that nonsense. It's just stupid to be honest. There's really no other word for it.

From experience, tube amps tend to be more expensive than solid state. That plus the art of designing them due to heat transfer and whatnot (I don't know how tube amps work yet). Something like the Bottlhead Crack is fairly inexpensive for a tube amp, and it's all analogue, which might be a buying decision for some. My dad really likes the whole analogue experience since he was born in that kind of era for example.
 
For solid state amps, it seems that most solid states that are more expensive have more inputs and outputs; the O2 only has 1 input, 1 output. I have to wonder how much work went into the SPL Phonitor for example since there are so many things that can be adjusted as for per headphone usage, something the O2 can't. Were the O2 a "one solution for all" thing, wouldn't professionals be using them and all that jazz?
 
As for soundstage, I, and others, have heard the JDS Labs C5 and its soundstage is smaller than that of the O2. It's one of the main reasons why I use it with the K 701 because with the O2 the K 701's [to me] wonky-sounding soundstage is somewhat alleviated with a smaller soundstage amp. Believe what you want, but I'm just posting my impressions and what I'm hearing. I'm not going to lie and say they sound exactly the same, because they don't, no matter what the numbers say, I hear a difference.

 

[JakeJack_2008]

I'd like to buy a new pair of preferably open back headphones: $190 - $299 and use them (only) with the ODAC and O2.
As I mentioned in this thread (and in the ODAC thread) I am using my DT 880 (250 Ohm; 2005 Edition) or  sometimes my Sennheiser HD 595 with the JDS Labs ODAC and O2 as two standalone units.
I am super happy. No complaints. .....but I would like to explore more.
 
I thought about buying the UHA-6S MKII, or iBasso D12, or the Dragonfly, or the latest Merridian Explorer, or the DacPort LX, etc.
but after reading all those discussions in this thread and in the relevant threads about the ODAC, UHA-6S MKII,    ,... DacPort LX, etc
I came to the conclusion that I do not need another dac or amp since the ODAC and O2 are excellent.
Furthermore since  headphones have the biggest impact on the sound  therefore I should focus on buying a better than the DT 880 pair of headphones instead of buying another DAC and headpnone amp. (At least for now.)
I'd like to buy something like AKG K701/702 or Q701, AT ATH-AD900X, Sony MA-900, also closed back AKG K 550, etc.
 
My music: rock/hard rock, mainstream metal and obviously some pop.
I do not  listen to rap/hip-hop, electronic, extreme metal, etc.
(For classical music I can use my Sennhesier HD 595.)
I am not aiming at headphones that, say, reproduce female vocals better than my DT 880s and  I don't care about this at all.
Also, I do not need bass-heavy headphones. Obviously some bass is needed for rock/metal.
 
I know that at least three factors are important in matching a headphone amp with a pair of headphones:
- impedance
- max input power
- sensitivity
 
I would prefer higher impedance headphones because of the channel imbalance at low volume levels of the O2. (I haven't tested my O2 for the channel imbalance yet.)
 
 
Recently, I read on this site that the sensitivity factor is more important for
higher-impedance-headphones than the impedance itself.
 
Since this is the thread about ODAC & O2 - although there many  philosophical discussions going on here - this is the best place to ask for an advice regarding matching the O2 with very good headphones (under $300) with the proper impedance, max input power and  above all sensitivity.
 
Thanx in advance.