[WilliamLeonhart]

  What kind of amp did you use for those headphones that had the shrill?

The DAC was either Aune T1 with stock tubes or ODAC. 
 
The amp was some sort of DIY solid-state.
 
I also remember listening to the K701 via a solid state amp that didn't give the shrill (based on exteriors alone I guess it was the LD MK5), but still it was way too cold and dry for my taste. Perhaps in term of cold-ness and dry-ness, I think the AKGs are only second to the DT880s. 

 

[MrMateoHead]

  I tend to disagree with your comment about the tube amp. Tube amps are specifically noted for changing the character of the sound you pass through them (much more so than solid state amps). And, in general, tube amps tend to "smooth the sound" and so to "remove shrillness" - at least to a degree. Therefore, I would expect the tube amp to "de-emphasize any shrillness that may be present in the headphones you're listening to".
 
If you find a lot of AKG phones a little harsh or shrill, you might want to try a different brand - like HiFiMan's (planars tend to sound smoother and the opposite of shrill).
 
Considering the relative costs, it probably makes more sense to select a set of headphones you like to begin with, than to select a set you don't entirely like, then go hunting for an amp that will alter them into something you do like

As an owner of O2 / ODAC / HE-400s (velour or modded pads), I should note that any "shrilliness" or harshness/thinness to the sound is typically related much more to the recording than to the equipment in question, in my experience over a couple years. The setup is very unforgiving and the HE-400s "treble" seems to be one of the main "controversies" for users, some finding it a little peaked and others finding it harsh or sibilant. Any issue with treble (and I tend to think ringing is the main problem) almost disappears when using the velour earpads (which improve the sound a lot but change the overall character a bit, with bass that is less warm).
 
I haven't hear other Hifiman phones, but I assume the 5XX series and 400i's are probably a lot smoother with the same great speed.

 

[Irenicus87]

Would the O2+ODAC be a significant improvement over the Asus Xonar Essence STX? In other words, would it be worth it? Or would it be better to get a standalone amp instead because the STX dac may be good enough?

 

[castleofargh]

  Would the O2+ODAC be a significant improvement over the Asus Xonar Essence STX? In other words, would it be worth it? Or would it be better to get a standalone amp instead because the STX dac may be good enough?

depends on what headphone you use. the STX measures pretty well if I remember the right model (ST is the basic stuff and STX the better one right?).
when I was looking into it, I think I gave up because the output impedance was 10ohm and I have a bunch of IEMs. but else everything seemed fine for most situations on that soundcard, even the power output.

 

[Irenicus87]

 
depends on what headphone you use.

Sennheiser HD 800.
 
And yes, I know many here are gonna tell me I need a dac+amp for ~2000$ but I can't afford that at this time, so I'm looking for something cheaper like O2+ODAC to have a decent sound until I can get higher end dac+amp. The STX doesn't really do it, I mean it's okay at the mid impedence setting, but just lacks substance and also sounds somewhat harsh in the treble, not sure if that comes from the amp or dac. Also please don't tell me to get other (cheaper) headphones, that's out of the question.

 

[dazzerfong]

  Sennheiser HD 800.
 
And yes, I know many here are gonna tell me I need a dac+amp for ~2000$ but I can't afford that at this time, so I'm looking for something cheaper like O2+ODAC to have a decent sound until I can get higher end dac+amp. The STX doesn't really do it, I mean it's okay at the mid impedence setting, but just lacks substance and also sounds somewhat harsh in the treble, not sure if that comes from the amp or dac. Also please don't tell me to get other (cheaper) headphones, that's out of the question.

If you want to tame the HD800's brightness, the O2/ODAC would be the opposite of what you'd want: perhaps a tube amp for the tubey mellow sound. If, however, you like the sound to be clean and unadulterated, the O2/ODAC is your guy.

 

[Bibo]

  Would the O2+ODAC be a significant improvement over the Asus Xonar Essence STX? In other words, would it be worth it? Or would it be better to get a standalone amp instead because the STX dac may be good enough?

The dac of the STX is good, no need not replace it with an ODAC IMO. I use a Titanium HD as dac together with an O2 amp and i am very satisfied. But my headphones are all much warmer sounding than HD800s. So I would look for a warmer sounding amp and keep the STX for now if I were you.

 

[Irenicus87]

  If you want to tame the HD800's brightness

No, that's not what I meant. I love their basic sound signature, else I wouldn't have bought them. I sampled them in 2 different stores previously and they didn't have that harshness like with the STX there. One had the Yamaha AS 700 (no headphone amp) and one had the Lehmann Audio Linear, which was much better. Is the latter considered neutral or warm? Seemed neutral to me. I definitely don't want to color the sound.
 
Generally, what would be more important to improve the sound? Dac or amp? According Bibo and also other people on here, the STX dac is quite good, so maybe I'll start with just an external amp and later get an external dac. Good idea?

 

[AlanU]

  No, that's not what I meant. I love their basic sound signature, else I wouldn't have bought them. I sampled them in 2 different stores previously and they didn't have that harshness like with the STX there. One had the Yamaha AS 700 (no headphone amp) and one had the Lehmann Audio Linear, which was much better. Is the latter considered neutral or warm? Seemed neutral to me. I definitely don't want to color the sound.
 
Generally, what would be more important to improve the sound? Dac or amp? According Bibo and also other people on here, the STX dac is quite good, so maybe I'll start with just an external amp and later get an external dac. Good idea?

 
Source is always king. I'd concentrate of a good dac and hope the amplifier does it's job in somewhat neutral amplification.
 
The 02 amp does a great job especially at it's price point.
 
In the $2000 CDN  dollar range I have yet to hear a sweet MIDS/ meaty DAC that provides holographic realistic sound when I compare it to my space tech labs tube DAC.
 
I'm quite sensitive to shrill and high's and my HD800's did acceptably well with my burson da160 with 02 amp. Adding my Grant fidelity tube buffer made a smoother presentation that with added realistic "meat" to the mids that made female jazz vocals much better in SQ. My approach was that the 02 dac can pretty well run most headphones on the market and it amplifies my manipulated "source".
 
What I love about the HD800's is that it's a great headphone that I can manipulate. When I experimented by adding my tube dac with additional rectifier unit to my 02 dac the sound quality was unreal. If I wanted more grunt and tighter bass I'd simply swap my tube buffer to a 6550 or kt66. If i wanted sublime vocals I'd use a 6L6GC tube. The sound quality with this inexpensive 02 amp shocked me. Removing the 02 amp from the equation and just using the amp section in my Burson Virtuoso was slightly better but no where near the $2000 price tag of the Burson. By swapping tubes you are NOT limited in manipulating the sound.....unless you want to own a handful of solid state dac's. IMO no solid state dac can excel in every music genre. Tube configurations you can drastically change the sound by rolling tubes. 
 
People can read the forums and drink koolaid all day long. You must experiment to satisfy your ears.
 
In my particular setup I would have used my $1000 burson da160, Grant fidelity tube buffer and 02 amp and had absolutely incredible enjoyment. I really dislike most solid state dac's (aprox $2000 +) presentation in music but that's my preference.
 
I would not buy new amp until your extremely happy with your source.

 

[Irenicus87]

AlanU, thanks for the input, but how would I change the dac but still use the amp with the STX card? I doubt that's possible. So either I replace both or only the amp by something external.
 
edit: I guess you meant the O2+ODAC
 
And anyway, I basically only came for a simple answer to the question whether the O2+ODAC is better than the STX (both as dac and amp), anyone here who has compared them?

 

[castleofargh]

your card seems to measure just fine and should already be mostly transparent if not totally so. trying to improve on transparent may not be audible be it on DAC or amp part. just check that you get enough power from your soundcard for the hd800 and that's about it.
what AlanU is explaining is more about coloring the sound than going for high fidelity. his system might very well measure worst than your soundcard because of that. not saying it's bad or wrong, just that he talks about getting closer to his taste, not closer to fidelity.

 

[AlanU]

  AlanU, thanks for the input, but how would I change the dac but still use the amp with the STX card? I doubt that's possible. So either I replace both or only the amp by something external.

I'm not familiar with the STX card. There is always excitement when purchasing gear. 
 
If I made a far fetched assumption I'd imagine just buying a single 02 amp with your onboard pci DAC would sound decent.  The DAC world seems to have similar good sound characteristic in the the sub $1000+ mark. Dac's are extremely personal.
 
Generally speaking I almost find most sabre dac chips have a sound signature that does not suite my music genre. The sweet mids seems thin.
 
I've heard decent realistic meaty vocals with the inexpensive Bellari ha540 amp. It sounds decent with added colour to the music. The Bellari took the edge off of the high's but of course there's always better out there.
 
Test  your headphones with as many amps/dacs as you can. Even my Burson Virtuoso 1793 dac i prefer to  listen to it through my tube buffer to add meat to the vocals. I'd rather manipulate the source and run a solid state amp. I will be buying another tube dac down the road and possibly buy a woo tube amp. To be honest my tube buffer with vintage sylvania's 6sn7 is making my current burson combo extremely pleasing. Without a lie the 02 amp is equally as good. Only when I use my Space tech tube dac with super rectifier  I top the performance.
 
Specs of components is not the "end all be all". The human ear can determine what sounds "natural" and "just right" even though some information is lost in the translation. Speaking to musician friends they look at this hyper detail dac's unrealistic. Stuff we discuss/debate on headfi is quite opposite to a musician playing live music. Natural sound in a venue is "real'. This is where I feel just listening to music that just "sounds right" to your ears is basically quest we simply need to find......not hearing every single details of the ventilation fan or toe tap in a recording. I find too much detail actually a distraction. Again.....everyone is different.

 

[AlanU]

  your card seems to measure just fine and should already be mostly transparent if not totally so. trying to improve on transparent may not be audible be it on DAC or amp part. just check that you get enough power from your soundcard for the hd800 and that's about it.
what AlanU is explaining is more about coloring the sound than going for high fidelity. his system might very well measure worst than your soundcard because of that. not saying it's bad or wrong, just that he talks about getting closer to his taste, not closer to fidelity.

so very true regarding colouring the sound.
 
When a person purchases a dac they are basically seeking a colourized interpretation of what the "designer" provides in a finished product. I wont even get into cabling as an addition to change sound signature
 
Dacs can sound close to one another but I often find that one will "sound" different to our human ear.
 
Regardless of 2 channel or headphones we are all seeking pleasing sound to our ears. That is in fact looking for media translated to analog music to your ears. This is all colourized to a certain extent and also how the music is mastered.
 
With my 2 channel and my tube dac setup I cant transform my system to sound perfect for classic rock, piano, strings, accapella, electronica fast beat to female jazz vocals. With a solid state dac you cannot roll of the highs and provide meaty vocals then suddenly change the "house sound" to meet upbeat fast precise beats for electronica. This where I'm quite surprised my Totem Earth speakers can do well in a wide variety of music. It can be fast and with tubes I can lay back the music with finesse. My totem forests could not match the speed of some electronica. But this is why I've been looking for a solid state dac to match more of the electronica side of my music even though swapping to kt66 or 6550 tubes can keep up with electronica. 
 
I find the HD800's an extremely versatile headphone in that I can lay it back or make it perform dynamically. This is where the source can be an "equalizer" in how you want to translate the music. The soundstage is quite large with the Hd800 but with tubes i can almost create an HD650 sound signature just by swapping tubes. The Hd650 does have an intimate smaller sound stage with heavy tones. Oddly I cannot get the meaty vocals from an hd650 using a Concero sabre HD dac even though the HD650 is a rich lush sounding headphone.
 
 My 02 amp does a good job in amplifying the source. This is where I manipulate the source to match the timbre of the music. Seems human ears love overtones and compression. I'm always looking for something pleasing to my ears........

 

[KeithEmo]

  so very true regarding colouring the sound.
 
When a person purchases a dac they are basically seeking a colourized interpretation of what the "designer" provides in a finished product. I wont even get into cabling as an addition to change sound signature
 
Dacs can sound close to one another but I often find that one will "sound" different to our human ear.
 
Regardless of 2 channel or headphones we are all seeking pleasing sound to our ears. That is in fact looking for media translated to analog music to your ears. This is all colourized to a certain extent and also how the music is mastered.
 
With my 2 channel and my tube dac setup I cant transform my system to sound perfect for classic rock, piano, strings, accapella, electronica fast beat to female jazz vocals. With a solid state dac you cannot roll of the highs and provide meaty vocals then suddenly change the "house sound" to meet upbeat fast precise beats for electronica. This where I'm quite surprised my Totem Earth speakers can do well in a wide variety of music. It can be fast and with tubes I can lay back the music with finesse. My totem forests could not match the speed of some electronica. But this is why I've been looking for a solid state dac to match more of the electronica side of my music even though swapping to kt66 or 6550 tubes can keep up with electronica. 
 
I find the HD800's an extremely versatile headphone in that I can lay it back or make it perform dynamically. This is where the source can be an "equalizer" in how you want to translate the music. The soundstage is quite large with the Hd800 but with tubes i can almost create an HD650 sound signature just by swapping tubes. The Hd650 does have an intimate smaller sound stage with heavy tones. Oddly I cannot get the meaty vocals from an hd650 using a Concero sabre HD dac even though the HD650 is a rich lush sounding headphone.
 
 My 02 amp does a good job in amplifying the source. This is where I manipulate the source to match the timbre of the music. Seems human ears love overtones and compression. I'm always looking for something pleasing to my ears........

 
I don't disagree with anything you've said - but I do think you're totally ignoring another option.... plain old digital editing. What you're doing is essentially establishing a collection of "EQ presets" (each of your separate pieces of equipment creates a certain set of colorations). It seems to me that buying a new piece of equipment "every time you want to add a preset" is the long - and expensive - way around. With a digital editor, you can do the same thing, except that you can have an unlimited number of options, and pretty much an unlimited amount of control over each. In fact, you can set a general EQ in your player for all 'electronica' songs, and a different one for "vocals" - or you can adjust certain favorites individually - and simply save the edited copy to play next time.
 
Assuming your goal is to create a pleasant set of colorations, it seems to me that a relatively simple and economical product like Izotope Ozone gives you more flexibility and options than a whole warehouse full of different DAcs and amps - and for a lot less money.
 
(Of course, that would eliminate the fun of playing with the equipment)

 
 

 

[upstateguy]

   
I don't disagree with anything you've said - but I do think you're totally ignoring another option.... plain old digital editing. What you're doing is essentially establishing a collection of "EQ presets" (each of your separate pieces of equipment creates a certain set of colorations). It seems to me that buying a new piece of equipment "every time you want to add a preset" is the long - and expensive - way around. With a digital editor, you can do the same thing, except that you can have an unlimited number of options, and pretty much an unlimited amount of control over each. In fact, you can set a general EQ in your player for all 'electronica' songs, and a different one for "vocals" - or you can adjust certain favorites individually - and simply save the edited copy to play next time.
 
Assuming your goal is to create a pleasant set of colorations, it seems to me that a relatively simple and economical product like Izotope Ozone gives you more flexibility and options than a whole warehouse full of different DAcs and amps - and for a lot less money.
 
(Of course, that would eliminate the fun of playing with the equipment)

 

 
+1  EQing. 
 
Why not start with the foobar plugins and equalizer, saving each equalizer preset as you go. 
 
In no time at all you will have a colorized setting that suits your taste for any music you want to listen to and the best thing about it is that you can uncheck the "equalizer enabled" box any time you want and hear the difference your EQ has made, or, turn it off and listen to the sound of your headphone with uncolored music.
 
And you can do this with the card you have without spending any money at all.
 
Edit to say:  (Of course, that would eliminate the fun of buying and playing with the equipment)