[xdog]

Hehe
From Schiit Audio
Modi:
Output Impedance: 75 ohms
 
 
Your 558 have mostly 60Ohms, with the middle bass having 600 Ohms,
Kind of very simplified explanation is that Modi puts just half of the power into not mid-bass section (half of the energy is eaten up~=-3db); while the midbass (~100Hz) gets very large part of it (almost all, 0db change).
Your integreated soundcard has most likely 1 Ohm meaning that almost 100% is send to the heaphone
You can check the chart on personalaudio.ru.
I have a similar situation with Beats Mixr when on xonar stx vs realtec (they have more bass on STX).
 
The situation with hd600 is kind of diffrent because by default they have in most of FR 300 Ohms, (but the hump is also 600 Ohms(.
 
 
 

 

[Lumos]

  Hehe
From Schiit Audio
Modi:
Output Impedance: 75 ohms
 
 
Your 558 have mostly 60Ohms, with the middle bass having 600 Ohms,
Kind of very simplified explanation is that Modi puts just half of the power into not mid-bass section (half of the energy is eaten up~=-3db); while the midbass (~100Hz) gets very large part of it (almost all, 0db change).
Your integreated soundcard has most likely 1 Ohm meaning that almost 100% is send to the heaphone
You can check the chart on personalaudio.ru.
I have a similar situation with Beats Mixr when on xonar stx vs realtec (they have more bass on STX).
 
The situation with hd600 is kind of diffrent because by default they have in most of FR 300 Ohms, (but the hump is also 600 Ohms(.
 
 
 
 

 
Oh dude Modi is DAC no one plugs headphone into the DAC, signal needs to be amplified... FYI, Magni (AMP) output imp. is less than 0.1 ohms

 

 

[fabiobueno]

 
So you have just great onboard sound then

 
haha no disrespect but what you are saying is impossible.
what is your onboard sound card? Realtek?
 
by the way I have Asus Xonar U3 output impedance is 23 Ohm and 598 sound much more worse...

Yes, it's Realtek. But why impossible? As far as I understood, it was the same experience the topic creator had, except with odac-o2-hd598 instead of modi-magni-hd558.
 
Other headphones sound a bit more detailed and spacious on odac+o2 tough. HD598 is the only one that behaves the opposite way. I suspect that the better bass extension in the odac+o2 is causing the drivers to go slightly out of control. Just a guess, but is the only explanation I can think of. On busy sounds (Iike symphonic metal) it can get very bad. Maybe my HD598 is a weird one. Maybe my ears are weird Who knows.

 

[Lumos]

  Yes, it's Realtek. But why impossible? As far as I understood, it was the same experience the topic creator had, except with odac-o2-hd598 instead of modi-magni-hd558.
 
Other headphones sound a bit more detailed and spacious on odac+o2 tough. HD598 is the only one that behaves the opposite way. I suspect that the better bass extension in the odac+o2 is causing the drivers to go slightly out of control. Just a guess, but is the only explanation I can think of. On busy sounds (Iike symphonic metal) it can get very bad. Maybe my HD598 is a weird one. Maybe my ears are weird Who knows.

haha NO!!! O2 and odac cannot and will not cause drivers to go out of control. quite contrary-high output impedance will cause reduction of electrical damping and 100Hz will resonate more.
 
Honestly, I suggest to listen better headphones with real bass extension and think again if you like what you hearing out of Realtek+598

 

[Gravit8]

 
haha NO!!! O2 and odac cannot and will not cause drivers to go out of control. quite contrary-high output impedance will cause reduction of electrical damping and 100Hz will resonate more.
 
Honestly, I suggest to listen better headphones with real bass extension and think again if you like what you hearing out of Realtek+598

The output impedance of the o2+odac is .54 Ohms, so very low.  I think the difference me and fabiobueno may be hearing is that the higher power of the amp is allowing that bottom end to fill out, veiling the mids and highs a bit.  This would be my best guess, but I'm still not completely sure.

 

[Marlene]

 
Honestly, I suggest to listen better headphones with real bass extension and think again if you like what you hearing out of Realtek+598

 
I have to ask: what do you have against the HD-598? It´s true, it lacks bass below 50-60 Hz... but I wouldn´t exactly call it bass shy. What are you listening to? Dr. Dre Beats?

 

[Lumos]

  The output impedance of the o2+odac is .54 Ohms, so very low.  I think the difference me and fabiobueno may be hearing is that the higher power of the amp is allowing that bottom end to fill out, veiling the mids and highs a bit.  This would be my best guess, but I'm still not completely sure.

The output impedance out of O2 is less then 1 Ohm. everything more then 2-3 Ohms are considered as high. O2 is kinda reference you can have to evaluate headphone performance. But anyway, if you like that you hearing out of onboard card from your computer that is great !!!

 
 

   
I have to ask: what do you have against the HD-598? It´s true, it lacks bass below 50-60 Hz... but I wouldn´t exactly call it bass shy. What are you listening to? Dr. Dre Beats?

Quite many headphones I have in my collection now, you can visit my profile and see,
these are:
AKG Q701
Beyerdinamic DT880 (600Ohm)
Sennheiser HD650
Sennheiser HD598
Shure SRH940
Sennheiser HD700
AKG K500
 
Had:
Sony MDR MA900
Alessandro MS1i
AKG K240 Studio
Sennheiser HD558
Koss KCS75
Audio-Technica M40
 
Had for long term loan or heard:
Beyer T1
Grado 80/225/325, my made woodied 80 for friend
Hifiman HE400
 
and many many more could not list everything... many amps and dacs also

 

[fabiobueno]

 
haha NO!!! O2 and odac cannot and will not cause drivers to go out of control. quite contrary-high output impedance will cause reduction of electrical damping and 100Hz will resonate more.
 
Honestly, I suggest to listen better headphones with real bass extension and think again if you like what you hearing out of Realtek+598

 
I'm not saying it's odac or O2 fault; the Realtek clearly have more bass roll-off, so what I thought is that my HD598 just can't handle the extra amount of low frequency content that the o2+odac provides. Again, it's just a guess. However, the fact that Gravit8 got "unveiled" sound from the Modi and Magni after eq down the bass may be an evidence.
 
I listened to other headphones... as I said, the HD598 was the only one to have this weird behavior 

 
Now I'm using HD800 btw. Still think the Realtek onboard fair quite well tough =P While odac and o2 are indeed more detailed, I wouldn't say it's a big difference. I even got another odac and o2 just to be sure I didn't have defective units 

 Then I bought a Schiit Vali. Wow! I almost wanted to throw the O2 out of the window. The Vali is that much better to my ears (including more bass extension and impact). I want to someday test the Vali with the HD598 and see if I'll also get "veiled" sound.
 
(My onboard audio is really crap with IEMs tough. With the SE535 there's so much noise that it's pratically impossible to listen to any music on it. But with full size headphones it never was an issue.)