E17 and E09K help

[Saxi]

I am using DT880 250 on my computer.  I wear these 8+ hours a day while I work and game.  I use them for music and gaming almost equally.
 
I was using Xonar STX w/ upgraded OpAmps, but I am looking at switching to a DAC/AMP to better quality sound.
My motherboard has a 110db SNR RealTek 898 with support for SoundBlaster X-Fi Xtreme Fidelity and EAX 5.
I'm using the motherboard audio right now while the STX is being sent to Asus for replacement.
 
I had a few questions though I can't find answers to.
 
From what I understand, the E17 will drive the DT880 250 and sounds great, is there any benefit to adding the E09K to the setup?
 
If using SPDIF for the computer, is this less quality than if using USB and completely bypassing the sound card?  I originally planned on doing USB to eliminate the sound card all together, but reading I see that using SPDIF will allow me to get some functionality of the on-board sound.  Does this mean I will keep full positional audio support from my on-board and EAX?  Would it be less quality than using USB only?
 
Will I need a SPDIF optical cable, or does it come with it?
 
Is there a way to put an additional 3.5mm inputs into this?   I have a Windows box (I would use USB or SPDIF), OSX Box (3.5mm) and PS3 (3.5mm) I would like to have all three inputs tied in.  Right now I'm using the Input jack on the STX with a 2-3.5mm->1-6.35mm splitter so I can use all three into my DT880.

 

[PurpleAngel]

The Essence STX and FiiO E09K use the same TI 6120 headphone amplifier chip.
 
Want some great sound, without the computer's electrical noise, Audio-GD NFB-11.32, $265
http://www.head-fi.org/t/686519/audio-gd-nfb-11-32-upgraded-tcxo-and-usb-chip-options-installed

 

[Saxi]

I assume the E17 would be similar then as well?
What is the advantage of using them both anyway?  Is it more power or volume?
 
Would using a SPDIF option give me similar computer gaming performance as an card or would I still lose better positional audio for gaming?
 
Thanks.

 

[PurpleAngel]

  I assume the E17 would be similar then as well?
What is the advantage of using them both anyway?  Is it more power or volume?
Would using a SPDIF option give me similar computer gaming performance as an card or would I still lose better positional audio for gaming?.

When the E17 is docked to the E09K, all the E17 provides to the E09K is the E17's DAC feature, the E17 does not add power or volume.
 
Using S/PDIF (optical or coaxial) allows the motherboard's on-board audio features to be used, while the E17 would be providing the DAC (Digital to Analog Converter) and amplification.

 

[Saxi]

So i would retain the ability to do CMSS-3D and EAX and other gaming related features?
If this is the case, is there anything you would recommend that would be a big step up from the STX that I can just use off the SPIF of the the on-board X-fi engine that's under $500.  If I can get something that would be a huge improvement over the STX and still keep positional audio I would be interesting in upgrading.
 
If the E17 is strong enough to power the DT880 (I'm not getting one as you said it is pretty much the same as the STX, I'm just curious) the E09K would provide zero benefit over a E17 solo right?  Would you use them both only if the E17 wasn't strong enough?  I still don't understand why you would use them both if the E17 can drive even the DT880  600 ohm..

 

[Chris J]

The E09K has far more power than the E17.
If you had an E17 you could drive a pair of DT880/600, but you may tend to clipping at high volumes with some bass heavy material.
The E09K would not have this problem with the DT880/600.

 

[PurpleAngel]

  So i would retain the ability to do CMSS-3D and EAX and other gaming related features?
If this is the case, is there anything you would recommend that would be a big step up from the STX that I can just use off the SPIF of the the on-board X-fi engine that's under $500.  If I can get something that would be a huge improvement over the STX and still keep positional audio I would be interesting in upgrading.
 
If the E17 is strong enough to power the DT880 (I'm not getting one as you said it is pretty much the same as the STX, I'm just curious) the E09K would provide zero benefit over a E17 solo right?  Would you use them both only if the E17 wasn't strong enough?  I still don't understand why you would use them both if the E17 can drive even the DT880  600 ohm..

My best guess is you would not want to use the Fiio E17 for driving 600-Ohm headphones.
I assuming you are planning on replacing your current DT250-Ohm with DT880 600-Ohm?

 

[Saxi]

 
My best guess is you would not want to use the Fiio E17 for driving 600-Ohm headphones.
I assuming you are planning on replacing your current DT250-Ohm with DT880 600-Ohm?

 
At some point I want to get the 600 ohm, but not on the STX. 
I was just curious why you would want the E09K if the E17 is powerful enough, out of curiosity, if the E17 can drive something properly, would using the E17 & E09K together give you anything more.
 
I would like to know of if I got a dac/amp that was much better than the STX and had SPDIF if I would be able to use CMSS-3D and EAX of the X-Fi through SPDIF with the sound quality of a better dac/amp. It would have to be significantly better than the STX to make it worth upgrading to but if there is something under $500 that would give me a big improvement while still having positional audio I would be interesting in upgrading.
 
Right now I am using the STX (temporarly using the onboard X-Fi till it gets replaced by Asus) and I am happy with it, but I feel the DT880 could do more, I wasn't as blown away by them as I would expect coming from PC350 and Logitech G35.  I suspect the STX is holding it back a bit.