[crazeman]

Hi, I've just recently brought a set of Sennheiser HD598 headphones and I've been reading that you generally need to get an amp to fully take advantage of the headphones. 
 
 
I'm a audio noob so just bear with me for a minute. I plan on using the headphones on my desktop computer and currently I am using a integrated audio card. Which would be better for me at this point? Should I go for a Asus Xonar Essence STX sound card or am I better off just getting a desktop DAC/amp?
 
Also how does the Xonar Essence compare to other DACs or amps? At which price point does a dedicated DAC + amp combination exceed the performance of the Xonar?
 
Thanks in advance!

 

[maverickronin]

The STX is a bad choice for the 598s.  Its amp has a 10 ohm output impedance that will seriously mess up the frequency response of the 598s.
 
Theirs nothing wrong with the STX's DAC section though.  IIRC Asus has a cheaper version with out the headphone amp that could get instead and pair with an amp.
 
What's you budget look like?

 

[tmars78]

Quote:

The STX is a bad choice for the 598s.  Its amp has a 10 ohm output impedance that will seriously mess up the frequency response of the 598s.
 
Theirs nothing wrong with the STX's DAC section though.  IIRC Asus has a cheaper version with out the headphone amp that could get instead and pair with an amp.
 
What's you budget look like?

I have the STX, and am still sorta noobish, so excuse me if this is a stupid question, but why will it mess up the frequency response? The 598s are 50 ohms, so shouldn't it screw up most headphones that are around the same ohms? Like the PortaPro which are 60 ohms? 

 

[Head Injury]

Quote:

I have the STX, and am still sorta noobish, so excuse me if this is a stupid question, but why will it mess up the frequency response? The 598s are 50 ohms, so shouldn't it screw up most headphones that are around the same ohms? Like the PortaPro which are 60 ohms? 

The HD598 (and similar Sennheisers) has a massive spike in the impedance curve at 90 Hz. With high output impedance, voltage is limited for low impedances, so any spike in the impedance curve is going to get more relative voltage than everything else. So you get more volume.
 
"Seriously mess up" might be a little much. The increased volume will be about 1.3 dB give or take. That's certainly enough to be audible, and it's in one of the worst places for a boost (extra unwanted mid-bass means muddy sound). The difference is a lot bigger than other headphones because of that spike. If the spike were, say, 100 ohms instead of 300, the difference would be only about 0.75 dB and inaudible or nearly.
 
At least I hope those are the right numbers.
 
50/60 = 0.833
300/310 = 0.968
20log(0.968/0.833) = 1.305

 

[maverickronin]

Whoops.  Looks like I messed something up when I did the math in my head.  Its not quite as big as I was thinking.

 

[tmars78]

Quote:

The HD598 (and similar Sennheisers) has a massive spike in the impedance curve at 90 Hz. With high output impedance, voltage is limited for low impedances, so any spike in the impedance curve is going to get more relative voltage than everything else. So you get more volume.
 
"Seriously mess up" might be a little much. The increased volume will be about 1.3 dB give or take. That's certainly enough to be audible, and it's in one of the worst places for a boost (extra unwanted mid-bass means muddy sound). The difference is a lot bigger than other headphones because of that spike. If the spike were, say, 100 ohms instead of 300, the difference would be only about 0.75 dB and inaudible or nearly.
 
At least I hope those are the right numbers.
 
50/60 = 0.833
300/310 = 0.968
20log(0.968/0.833) = 1.305

 
Thanks. I had seen it mentioned before that the STX was bad for these headphones, but never asked why. And yeah, I can pick out a 1 DB difference with ease, so 1.3 would definitely be audible. 

 

[crazeman]

Quote:

The STX is a bad choice for the 598s.  Its amp has a 10 ohm output impedance that will seriously mess up the frequency response of the 598s.
 
Theirs nothing wrong with the STX's DAC section though.  IIRC Asus has a cheaper version with out the headphone amp that could get instead and pair with an amp.
 
What's you budget look like?

 
I'm willing to spend around $200-300 for a amp/DAC. I've scanned through the amps/dacs listed on Head-fi, but most of them seems to be over my budget and insanely expensive to spend on something that I'm just starting to get into.
 
I really don't know much about audio equipment and have no idea about impedance or ohms. I had a friend who recently got a fiio e5 recently and that was my first experience with an amp. I thought everything sounded much better when I hooked it up to his computer with my HD598 so I wanted to get one myself.

 

[maverickronin]

I messed up the math so the STX isn't as bad as I thought it was with the 598s so it could work fairly well compared to the usual onboard audio.  If you can't find a card with about the same quality line out but is cheaper because it leaves off the headphone amp you get just get the STX and use its headphone amp for a while and save up a little more for a good but cheap amp like the Objective2.

 

[daerron]

The Essence STX should be more than good enough until you can save up for a desktop amp to use with the lineout. I used the amp on my Essence STX for about a year before I eventually had money for a desktop amp. The desktop amp definitely did improve matters but I didn't note that much difference with the HD595 I had at the time. But definitely worth giving the Essence STX a shot with the HD598, should be a real good bang for the buck solution.

 

[joms]

Hi.
 
I'd just like to revive this thread because im looking for a way to power this:
 
a) AKG K550 = on my office desktop
b) HD 600 = on my home desktop
 
My desktop has an extra PCI-E slot so i can either get the asus or a desktop amp.
 
 
Other Questions:
1) What desktop amp is comparable to the asus?
2) Is the Asus better/same/worse than the JDS O2?
3) Is the Asus better/same/worse than the Hifiman EF2a?
 
Thanks