I was originally going to make this a guide, but since it was SO difficult, I cannot recommend that *anyone* undertake this mod. Therefore, the only people who will do this are the people who are so confident with their soldering ability that they will go ahead and do this anyway, despite the warnings and recommendations against doing this.
Just in case you missed it:
DO NOT DO THIS MOD AND BLAME ME WHEN YOU MESS UP AND RENDER YOUR X-FI USELESS
Ok, so now you got that in your mind (hopefully), on with the show
I followed the guide and following posts on the excellent thread/guide at Head-fi.org: Hotrodding the X-Fi: A Layman's Guide
Full credit to cotdt for making his guide, else I would not even have bought an X-Fi
Basically, there are four op-amps. These take the output from the DAC (digital-to-analogue converter). One is for the front left and right, the remaining three do the other six channels. Something like one is centre/side-right, one rear-left/side-left, one rear-right/sub.
For improving the main left and right channels you replace the op-amp circled in red, to upgrade any of the surround channels, you have to upgrade all of the remaining op-amps circled in green. It doesn't really make sense to replace just one of the surround op-amps because of the way the channels are assigned to each op-amp.
The power filter capacitor on the X-Fi smoothes the voltage used by the card, so replacing it with a better quality capacitor will give better quality power, and in turn, better sound.
Solder braid is essential for soaking up the solder around the op-amp
So here is a stick of the new op-amps:
And here is a bag of the caps:
Ok, work begins, snipped off the main op-amp using micro side-cutters (the stock one, not the new one lol)
Tada, no more op-amp:
I could not for the life of me touch the leg of the new op-amp to solder it and not move it out of place (since it's a surface mount component it just slides around really easily), so I used some cunning masking tape. That showed it who's boss!!!
Desoldering the capacitor really is as hard as everyone says it is. The PCB just takes away all the heat and it seems as though your iron isn't even on. Finally ending up at maximum heat and after some solder soaking with the braid and a bit of light pulling the capacitor on the other side and one leg came out nice and clean. After a lot of messing about the other leg finally came out but left a load of solder in the hole... this was SO hard to get out, every time you try and heat it to get it out, the board heats and so the solder just clings to the inside of the hole!!! If you had an iron bit tapered to a sharp needle point, that might work. I had to use my regular bit that tapers to 1mm, a 1.5mm drill bit (also some sub millimetre drill bits turned by hand could work here), an actual needle, flux, and a lot of beer!!! I drank the beer, it's not a secret desoldering chemical, just in case you go WAHEY and throw some beer on your card or something
Erm, where was I then, oh yeah, capacitor desoldered:
Here's a little comparison of the old (small) and the new (big) capacitors... It's not really a case of bigger is better, it's more a case of Blackgate are some of the best capacitors in the world, and the stock one, well... isn't.
You can only imagine how happy I was to take this picture of the new capacitor soldered in place. The op-amp took like 3-5 minutes including taking photos. The capacitor, I don't even know how long it took, maybe an hour, two hours? Probably more like an hour cos I had two glasses of beer or so. Quite a long time for one bloody component in anyone's book!
Ok, and so here is the new cap in place on the board.
Look back at the stock cap photos to see the difference lol. Remember, you shouldn't do this mod, but if you completely mental or just a soldering iron god, you can bend the capacitor over if you have clearance issues. You shouldn't have clearance issues mounting it like me, and keeping the legs as shorts as possible is ideal, but you're not going to do this mod anyway are you.
So maybe you're wondering "what the hell? why go to all that trouble?". Well, if audio quality is really important to you (it is to me) then improving the sound of an X-Fi to match the sound reproduction of some really top-notch audio gear is definitely worth the effort.
I really don't want to ever have to desolder a capacitor like that ever again lol. Maybe if I had a 200 watt soldering iron or something
Maybe I should hardmod my soldering iron, hahahhahahaha!
Nah, I don't fancy an exploding ball of molten plastic in my hand and eyes in the middle of soldering lol.
The audio difference:
I haven't tested this yet with RMAA, but subjectively, the sound appears to be coming further from the left and right, it's noticeably clearer, kinda like if you had ears kinda waxy and then cleaned them out and it feels like you have Superman hearing, kinda like that. Not totally waxy or so bunged up like you got water in your ears, but meh... Hopefully someone knows what I'm talking about. It's sorta feels like I upgraded my ears.
The sound almost has a live quality about it now, I can almost see the music now, again the difference is semi-subtle, but definitely there.
I'll do some RMAA tests at some point to try and show some figures/graphs etc.