Head-Fi.org › Forums › Equipment Forums › Headphone Amps (full-size) › O2 AMP + ODAC
New Posts  All Forums:Forum Nav:

O2 AMP + ODAC - Page 124

post #1846 of 3174
We cannot control what happens in the studio but we can expect most producers/engineers to be working with neutral set ups. And this shows given that most modern recordings sound perfect on the HD800s to me using the O2 . And as for the inner fidelity graph. That is a headphone response , headphone frequency responses are not suppose to be flat because their FR should represent speakers in a room. By the time the sound reaches our ears from flat speakers in a treated room then it looks more like that curved frequency response therefore being perceived as flat by our ears and brains. Therefore it is like listening to flat speakers , so it sounds neutral. If you had a perfectly flat FR on them inner fidelity graphs the actual perceived sound wouldn't be realistic .
Edited by James-uk - 1/6/14 at 1:28am
post #1847 of 3174

After all that said, I still haven't found a reliable answer for my initial question which was:

 

"based on the innerfidelity's impedance graph (http://www.innerfidelity.com/images/SennheiserHD800.pdf) for lower frequencies, the HD800 requires ~640 ohms! Would the O2 be able to properly drive the HD800 to bring out the best from the HD800 when it comes to bass?"

post #1848 of 3174
Yes the O2 can handle that impedance curve.
post #1849 of 3174
THD+N vs OUTPUT & MAX POWER ON AC: At 1 Khz with both channels driven here’s the distortion versus output on AC power into 15, 33, 80, 150 and 600 ohms. At 150 & 600 Ohms the output voltage was essentially the same at about 7.3 volts RMS. And even at about 200 mW of output into any of the loads the distortion is still below about 0.0025%! Maximum power is about 640 mW at 80 ohms. The power limits shown below exceed the power requirements established for the assumed worst case headphones (HiFiMan planars and 600 ohm version of the Beyer DT880):
post #1850 of 3174
Quote:
Originally Posted by miceblue View Post

Objectively, the HD800 isn't neutral either.
http://www.innerfidelity.com/images/SennheiserHD800.pdf
Bass roll-off at 70 Hz and the brightness at 4-8 kHz are pretty noticeable to many people, myself included.
 

 

Roll-off be roughly 1db (70Hz) sorry but this not worth mentioning.

 

Quote:
Originally Posted by James-uk View Post

I want to hear every last bit of music as the artist intended. That's why I love the HD800 paired with a transparent amp such as the O2. This pairing does exactly that . I can see how this is transparency isn't for everyone though, we all have a flavour when it comes to the sound we like, when I buy a new album from a favourite band or artist I always hope that is been recorded /mastered to my taste but ultimately The goal of high fidelity sound is transparency .

 

I'm on your side. I found my combo HD800 + O2 amazing. Simply neutral and that is perfect for most of my records.

post #1851 of 3174
So I'm interested in getting an o2. I'm currently using the modi-vali. I'm beginning to realize that it can't drive all my headphones. Maybe only 2 of them. Is the odac necessary for me since I have the modi? Is the performance similar? I can save some money just getting the o2 amp. Any pros and cons I haven't thought of? I would have just gotten the magni but the gain seems too high that 5x. I set my PC volume at 100. Should I get the low gain mod on the o2 or just regular? I'm driving grados HF-1 and HF-2.
Edited by nabwong - 1/6/14 at 5:21am
post #1852 of 3174
Quote:
Originally Posted by James-uk View Post

THD+N vs OUTPUT & MAX POWER ON AC: At 1 Khz with both channels driven here’s the distortion versus output on AC power into 15, 33, 80, 150 and 600 ohms. At 150 & 600 Ohms the output voltage was essentially the same at about 7.3 volts RMS. And even at about 200 mW of output into any of the loads the distortion is still below about 0.0025%! Maximum power is about 640 mW at 80 ohms. The power limits shown below exceed the power requirements established for the assumed worst case headphones (HiFiMan planars and 600 ohm version of the Beyer DT880):


Thanks for your answer!

post #1853 of 3174

O2 is a high end amp when it comes to providing a very, very affordable heaphone amp that delivers a very high end audiophile experience.

 

Straight wire with gain.

 

It doesn't come in a 20 pound 1/4 thick walled aluminum chassis.

 

It doesn't come with a 40 pound external power supply.

 

It doesn't come with all the bells and whistles that are associated with "high end" or "high cost'.

 

It just does what it does very, very well.

 

You may wear out the power on/off switch after 1000 or 2000 cycles or so...not a high end component.

 

But for around $100  or so its indeed an exceptional audio device that compares very well with the so called "high end" devices out there from an audio perspective..

 

Alex

post #1854 of 3174
Quote:
Originally Posted by TheDuke990 View Post

Quote:
Originally Posted by miceblue View Post

Objectively, the HD800 isn't neutral either.
http://www.innerfidelity.com/images/SennheiserHD800.pdf

Bass roll-off at 70 Hz and the brightness at 4-8 kHz are pretty noticeable to many people, myself included.

 

Roll-off be roughly 1db (70Hz) sorry but this not worth mentioning.
http://en.wikipedia.org/wiki/Just-noticeable_difference
1 dB is noticeable.
Quote:
Originally Posted by James-uk View Post

We cannot control what happens in the studio but we can expect most producers/engineers to be working with neutral set ups. And this shows given that most modern recordings sound perfect on the HD800s to me using the O2 . And as for the inner fidelity graph. That is a headphone response , headphone frequency responses are not suppose to be flat because their FR should represent speakers in a room. By the time the sound reaches our ears from flat speakers in a treated room then it looks more like that curved frequency response therefore being perceived as flat by our ears and brains. Therefore it is like listening to flat speakers , so it sounds neutral. If you had a perfectly flat FR on them inner fidelity graphs the actual perceived sound wouldn't be realistic .
I didn't say it was supposed to be flat, and the roll-off at 70 dB isn't neutral by any definition.
http://www.headphone.com/learning-center/about-headphone-measurements.php
Edited by miceblue - 1/6/14 at 11:50am
post #1855 of 3174
And in mids and treble we have more than 5 to 10db differences from the "zero line". Sorry but for me 1db is not worth to mention at all.
post #1856 of 3174
Quote:
Originally Posted by nabwong View Post

So I'm interested in getting an o2. I'm currently using the modi-vali. I'm beginning to realize that it can't drive all my headphones. Maybe only 2 of them. Is the odac necessary for me since I have the modi? Is the performance similar? I can save some money just getting the o2 amp. Any pros and cons I haven't thought of? I would have just gotten the magni but the gain seems too high that 5x. I set my PC volume at 100. Should I get the low gain mod on the o2 or just regular? I'm driving grados HF-1 and HF-2.

 

If you already own a dac, I do not see the point in buying the odac. The o2 comes with the 2.5x and 6.5x gain. I personally use 1x and 2.5x after removing the resistor myself. 

post #1857 of 3174
Quote:
Originally Posted by AsianBatman View Post
 

 

If you already own a dac, I do not see the point in buying the odac. The o2 comes with the 2.5x and 6.5x gain. I personally use 1x and 2.5x after removing the resistor myself. 


If you want a completely black background, than the ODAC is a good way to get it! I used the O2 with my computer's realtek chipset for awhile and while the noise levels were typically below what I could detect, the ODAC eliminated any background hiss.

post #1858 of 3174
Quote:
Originally Posted by AsianBatman View Post

If you already own a dac, I do not see the point in buying the odac. The o2 comes with the 2.5x and 6.5x gain. I personally use 1x and 2.5x after removing the resistor myself. 

Thanks. I just got a o2+odac from a friend and will do a modi-vali comparison. Can't wait for it to arrive.
post #1859 of 3174
Quote:
Originally Posted by adydula View Post
 

O2 is a high end amp when it comes to providing a very, very affordable heaphone amp that delivers a very high end audiophile experience.

 

It doesn't come with all the bells and whistles that are associated with "high end" or "high cost'

 

It just does what it does very, very well.

 

But for around $100  or so its indeed an exceptional audio device that compares very well with the so called "high end" devices out there from an audio perspective..

 

Alex

+1, I fully agree with you, don't need to spend much more to get the same results

post #1860 of 3174

:)

New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Headphone Amps (full-size)
Head-Fi.org › Forums › Equipment Forums › Headphone Amps (full-size) › O2 AMP + ODAC