X-FI Front 5.25'' I/O drive Opamp change

[Swamp Monster]

I want to change Opamp for front headphone output from stock NJM4556A to LM4562MA. Only problem is - looks like it's in series with another opamp - M33078. So there is no point changing only one, if they are in series. I think for sound quality improvement I need to change them both.

1)Is it ok to change them both with the same opamps? (NJM4556A and M33078 specs are very similar)
2)Can anyone tell what is M33078 purpose in this schematic? (Do I really need to replace it if I use headphone out only)

I hope there is some kind of sound guru that knows this.
Usually people are modding only soundcards, I haven't seen modded I/O panel, so no results in google.
I have ordered only one opamp for now, to solder it in NJM4556A place.

1st pic is orginal, second is purchased Opamp and 3rd is already modded card.

 

[Nickolas]

I'm trying to find that out as well. I can't see what's part of the headphone input and what's not. If I find anything, I'll contact you as soon as possible.

 

[Ross211]

Not sure on this but you might post this in Guru3D's Opamps and Modding thread

I think ROBSCIX will be able to tell you (he is Guru3D's audio editor / reviewer).

 

[Swamp Monster]

Thanks a lot guyz, I'll try Guru3D, looks like they are doing something similar indeed
I haven't touched that opamps on my card yet, still gathering info. Good to know that I'm not the only one doing this.
*edit* Today I replaced NJM4556A to LM4562MA. I will test it in few minutes.

 

[Nickolas]

Ah. Please tell me if it works and if you replaced the right one.
Are you still thinking of replacing the capacitors? I think I'll do that, but I can't find which ones to replace.

 

[Swamp Monster]

I changed it and it works! I will get better picture of that card after a few hours. Bass is more responsive and accurate and I hear more details in music, but major changes are that singers seems closer to me. It's like I am not listening to sound in my headphones, but directly in my head. (Vocals are "right in my face") It's different sound than from default opamp, I still need to get used to it, but it sounds good.

*edit* I didn't change any capacitors, because I couldn't find good ones in short time

 

[Nickolas]

Do you know which ones to replace?

 

[Swamp Monster]

NJM4556A right next to headphone connector.

*edit* Changed description in picture, now it's right.
*edit2* About capacitors - Two small ones below volume potentiometer are coupling caps. 16V/22uF. I think low ESR type would be good there, like OSCON.

 

[AsRock]

I changed it and it works! I will get better picture of that card after a few hours. Bass is more responsive and accurate and I hear more details in music, but major changes are that singers seems closer to me. It's like I am not listening to sound in my headphones, but directly in my head. (Vocals are "right in my face") It's different sound than from default opamp, I still need to get used to it, but it sounds good.

*edit* I didn't change any capacitors, because I couldn't find good ones in short time

Sounds like it's more forceful were as the original was more neutral or even laid back so to speak.

Grats in getting it done and working.. And glad ya like it..