[rvcjew]

  First of all thanks a bunch for your effort. As you suggested, I pluged my headphones into the headpohone out on the volume console of the 2.1System and yes, distortion is there as well.
I tried the RCA Pre-Out on the Denon Amp, but I wasnt able to get Sound.
 
To sum up: Setting is always 100% Windows Volume.
1) XonarSTX ->RCA Out -> 2.1System = Distoriton
    XonarSTX ->RCA Out -> 2.1System > Headphones on Headphone Out = Distoriton
    Xonar STX->RCA Out -> Headphones = No distortion
 
    Xonar STX-> Denon Amp= No distortion
    Xonar STX-> DVD Player RCA input = No distortion
 
2) 2.1System. -> Notebook = No distortion
    2.1System -> Iphone full Volume = No distortion
    2.1System -> SamePc with OnBoard Soundcard = No distortion
One note: Since the Notebook, Iphone and Onboard have 3,5mm out, im using a 3,5mm to RCA LR adapter into the 2.1System.
 
Finally I just want to remember that setting Windows Volume to around 60% and lower, solves the distortion problem with the STX-2.1 Setup.
 
^^Any Ideas?

Odd are you using stock or uni drivers, stock has an issue at 80-100 volume but your headphones should have gotten that too?

 

[MrHeadphone]

  Odd are you using stock or uni drivers, stock has an issue at 80-100 volume but your headphones should have gotten that too?

Im using stock drivers. Just tested my headphones on the Stx Rca again and it sounds fine. So when my headphones connected directly to the STX RCA have no distortion, that means that there is nothing wrong with my soundcard, right? What do you mean stock has an issue at 80-100? Didnt know about that.
 
Eventhoguh I dont have enough knowledge to back this up, but my explanation would be that the preamp of the STX is simply too strong for the 2.1Amp to handle. Because the Denon Amp has more watt, and better quality, I guess thats why the STX sounds fine even on 100% volume.
 
My conclusion would be, that neither my soundcard or my 2.1 system is broken. Correct me if im wrong.
Thank you again for your time and ideas.

 

[rvcjew]

I would agree with that the question is how to fix the problem.

 

[MrHeadphone]

  I would agree with that the question is how to fix the problem.

 
The solution would be to keep windows volume below 60% and turn up 2.1System Volume.
But there is another question i have about volume:
 
In general, what is the better volume balance, keep soundcard low and amp high or other way around?
 
EDID: Is there another way you know of to fix this problem?

 

[rvcjew]

   
The solution would be to keep windows volume below 60% and turn up 2.1System Volume.
But there is another question i have about volume:
 
In general, what is the better volume balance, keep soundcard low and amp high or other way around?
 
EDID: Is there another way you know of to fix this problem?

Normally you have volume all the way up on the stx so that it is at line out volume, then you use the amp for volume. 

 

[WeirdChild]

Settled at DUAL SOIC LME49990 for a while and now I just took the plunge and ordered 3 Dual opamps from Burson (V5 model), will post a review once I get them running.

 

[spidermad]

I've just installed these and been really happy so far.

 

[WeirdChild]

This is not review per se. This is a short story...  

Hi!

Been a happy owner of the Xonar SXT for some years now. Was really impressed from the first time since it gave life to my old crappy set of headphones, but I wanted more joy, so  almost right after I got the card acquired a nice set of headphones that have been my main drivers since then (Sennheiser 650HD). I was all happy and rediscovering the music I love and such. One day while reading thoroughly this thread took I the plunge and ordered 3 DUAL SOIC LME49990 DIP8 opamps to upgrade my the STX. Once again I was impressed.

Settled up for long time and totally forgot about improving the sound, you know, work, travels, life and other everyday issues kept me busy. I still enjoyed the sound and had a lot of fun for sure. So after a while, life became more easy going, more steady (so did work), and had the need to invest into better sound gear. So yeah, I bought my first headphone amplifier and was mesmerized by the great improvement. Along acquiring a tube amp comes the urge to improve it with better tubes (some of you can relate) and so I did, got into rube rolling and once again, results were there!

One day I was thinking of getting a new DAC, was looking into some models, calculating budget, etc. Then I looked at my long time friend, the STX and thought of getting those weird looking op amps I once read about, the old Burson ones. So I emailed Burson and said I wanted them for my card, they answered and said they had a new, improved and more compact model that fits better into the STX.

Took me a day to decide whether to get them or not, I always had the option to buy an external DAC, but I am emotionally attached to the STX, then I said, let's upgrade this fella!
 
So I took the plunge and ordered 3 dual op amps for the STX, the reasons I did so were:
 
-Life time warranty.
-Same as above, whenever I feel it is time to replace the STX (not soon) and buy an external DAC that has the option to roll op amps I can move the Bursons there. 

Hope you are not bored by the rant yet, so let's look at some pictures: 

 
Picture 1: Location of the LME49990.
 

 
Picture 2: Burson Supreme Sound Opamp V5 in the case they came with. Banana for scale.
 

 
Picture 3: Another comparison picture.
 

 
Picture 4: After removing the Xonar STX from the case I knew of course, the shield from the card wont be needed anymore so I put it away in a safe location. Then I installed one V5. 
 
 

 
Picture 5: So now we have the 3 op amps installed in the card. Easy stuff. Things looking good so far.
 

 
Picture 6: Top view. Double checked the op amps were installed in the right position. One concern before install... I was wondering if I had enough space inside the case, my STX in the far bottom slot... Even though the V5's are not that tall once installed in the card the whole thing is takes more vertical space than an average video card...so let's see what happens.
 

 
Picture 7: Wow, that was close. Had enough space to keep the STX in that slot! Of course you can always move your card to another slot, but in my case, I did not want to. So yeah, pretty good by now.
 

 
 
 
Overall Results:

-Music sounded clearer.
-Separation of instruments very much improved.
-Instruments seem to have better, more real mass (hard to explain) and of course an improved sound stage.
-More layers of sound?
-I don't recall that song having that instrument.
-More enjoyable experience.
-Going to keep the STX for a long time. 
 
 
 
Final thoughts:

I am very happy with my purchase. Justified purchase buck by buck? Depends on how much you want to push the STX. But surely the Bursons do their job and help you take your card to a next level. But do not let your wife know how much these little things cost. LOL. 
 

 
English is not my first language. 
 
Cheers.

 

[y0d4]

  Yes, those should do.
 
By the way, about the NE5532/4, it's worth noting that these are recommended by default in the datasheet for the IV stage as being guaranteed to reproduce the datasheet performance figures for the DAC. Don't let the low price put you off, they are very good for general purpose audio.

Hi rjm003, i successful replace like you said and ... sound is little "dirty" compare with stuck, but to be honest i like it more then original, because bass is more massive which i like it.
Voices are richer, only high freq. are little "stolid", but don`t care, general i am satisfied with this change.
thank you one more time!
BR.

 

[saddleup]

@ WeirdChild.  Thanks for the review and photos.

 

[xPakrikx]

 
This is not review per se. This is a short story...  

Hi!

Been a happy owner of the Xonar SXT for some years now. Was really impressed from the first time since it gave life to my old crappy set of headphones, but I wanted more joy, so  almost right after I got the card acquired a nice set of headphones that have been my main drivers since then (Sennheiser 650HD). I was all happy and rediscovering the music I love and such. One day while reading thoroughly this thread took I the plunge and ordered 3 DUAL SOIC LME49990 DIP8 opamps to upgrade my the STX. Once again I was impressed.

Settled up for long time and totally forgot about improving the sound, you know, work, travels, life and other everyday issues kept me busy. I still enjoyed the sound and had a lot of fun for sure. So after a while, life became more easy going, more steady (so did work), and had the need to invest into better sound gear. So yeah, I bought my first headphone amplifier and was mesmerized by the great improvement. Along acquiring a tube amp comes the urge to improve it with better tubes (some of you can relate) and so I did, got into rube rolling and once again, results were there!

One day I was thinking of getting a new DAC, was looking into some models, calculating budget, etc. Then I looked at my long time friend, the STX and thought of getting those weird looking op amps I once read about, the old Burson ones. So I emailed Burson and said I wanted them for my card, they answered and said they had a new, improved and more compact model that fits better into the STX.

Took me a day to decide whether to get them or not, I always had the option to buy an external DAC, but I am emotionally attached to the STX, then I said, let's upgrade this fella!
 
So I took the plunge and ordered 3 dual op amps for the STX, the reasons I did so were:
 
-Life time warranty.
-Same as above, whenever I feel it is time to replace the STX (not soon) and buy an external DAC that has the option to roll op amps I can move the Bursons there. 

Hope you are not bored by the rant yet, so let's look at some pictures: 

 
Picture 1: Location of the LME49990.
 

 
Picture 2: Burson Supreme Sound Opamp V5 in the case they came with. Banana for scale.
 

 
Picture 3: Another comparison picture.
 

 
Picture 4: After removing the Xonar STX from the case I knew of course, the shield from the card wont be needed anymore so I put it away in a safe location. Then I installed one V5. 
 
 

 
Picture 5: So now we have the 3 op amps installed in the card. Easy stuff. Things looking good so far.
 

 
Picture 6: Top view. Double checked the op amps were installed in the right position. One concern before install... I was wondering if I had enough space inside the case, my STX in the far bottom slot... Even though the V5's are not that tall once installed in the card the whole thing is takes more vertical space than an average video card...so let's see what happens.
 

 
Picture 7: Wow, that was close. Had enough space to keep the STX in that slot! Of course you can always move your card to another slot, but in my case, I did not want to. So yeah, pretty good by now.
 

 
 
 
Overall Results:

-Music sounded clearer.
-Separation of instruments very much improved.
-Instruments seem to have better, more real mass (hard to explain) and of course an improved sound stage.
-More layers of sound?
-I don't recall that song having that instrument.
-More enjoyable experience.
-Going to keep the STX for a long time. 
 
 
 
Final thoughts:

I am very happy with my purchase. Justified purchase buck by buck? Depends on how much you want to push the STX. But surely the Bursons do their job and help you take your card to a next level. But do not let your wife know how much these little things cost. LOL. 
 

 
English is not my first language. 
 
Cheers.

Nice
 
I plan buy this oamps as my christmas gift for myself , now i use original oamps. But i must use extension cabels for dip8 :| custom made 10cm . I have Jonsboo C3 case and Asus v gene MB , sound card use last PCI-E stol , there is no space .
 
Hmmm my girlfrend knows how much these things cost, and now, i am little kid, for her
but she understands it.
maybe

 

[WeirdChild]

  Nice
 
I plan buy this oamps as my christmas gift for myself , now i use original oamps. But i must use extension cabels for dip8 :| custom made 10cm . I have Jonsboo C3 case and Asus v gene MB , sound card use last PCI-E stol , there is no space .
 
Hmmm my girlfrend knows how much these things cost, and now, i am little kid, for her
but she understands it.
maybe

 
Hi! I have a somewhat large case but all the other slots were not available. But in your case the extensions will work good! I was just kidding, my fiancee is very supportive of my hobby, how can she not be? She enjoys music as much as I do. In fact she is a better judge than me, I like it when she says "Oh that song sounds much better now". 

 
And yes, we are like little kids! Hope you get them by christmas, or whatever you want to get, the thing like I say is to enjoy life more, if music is a big part of your life, so be it. And like I said, I am happy I am sticking to the STX and it deserved a this great upgrade.
 
Cheers!

 

 

[x3dnd3x]

How does the V5 opamp sound?

 

[diforce]

How does the STX perform with low impedance phones such as Fostex T50 RP ? they are 50 ohms. 
 
also does changing the OP AMPS to better ones actually makes it better ( aka it was tested on proper testing equipment )  or is it all audiophile voodoo ? 

 

[verde57]

Opams, shore do make a difference. The ST/X goes well with low impedance headphones, with high imp. ones they loose "fullness" of sound.
Also a big, big difference in sound quality(precision, details) is achieved by modding the crystal oscillator, just like it is showed here somewhere with the big Vanguard quartz.