[DaWolf1205]

Hello everyone,
 
I am using an HD558 and I am interested in trying out different OP AMP chips on my new sound card. I am currently using the LME49720NA, which I purchased from here: http://www.digikey.com/product-detail/en/LME49720NA%2FNOPB/LME49720NA%2FNOPB-ND/1647708
 
but I'm wondering if there are any other chips I could try out to see if I can get any better sound.
 
I listen to mostly instrumental music (FLAC), like soundtracks for movies, games, etc. I also watch a lot of HD movies on my PC.
 
Any help would be greatly appreciated.

 

[PurpleAngel]

  Hello everyone,
I am using an HD555 and I am interested in trying out different OP AMP chips on my new sound card. I am currently using the LME49720NA, which I purchased from here: http://www.digikey.com/product-detail/en/LME49720NA%2FNOPB/LME49720NA%2FNOPB-ND/1647708
but I'm wondering if there are any other chips I could try out to see if I can get any better sound.
I listen to mostly instrumental music (FLAC), like soundtracks for movies, games, etc. I also watch a lot of HD movies on my PC.
Any help would be greatly appreciated.

You might consider selling off the HD555 and getting a (used) HD558.
 
Check out the AD797BR and LME49990 op-amps.

 

[DaWolf1205]

Sorry, I'm an idiot, I meant to type HD558. I've also modded them by removing the foam on the inside, which apparently makes these equal to a HD598 now.
 
Thanks for the suggestions though, I'll check those out.
EDIT: After looking up those chips on digikey, it looks like they aren't the type that fit into the socket on the Asus Xonar DSX. I apologize if I'm missing something, I'm still new to this.

 

[Bobby S]

Opamps come in 2 distinct form factors: DIP and SOIC .
What you need is DIP package (SOIC are smaller, surface mount type chips).
 
So, for AD797 you need to be looking at the AD797AN, the only DIP version of this opamp: http://www.digikey.com/product-detail/en/AD797ANZ/AD797ANZ-ND/751113
All others are SOIC, as is the LME49990.
 
That being said, you can use SOIC opamps too, in conjuction with an SOIC to DIP adapter. But that requires some soldering skill.

 

[Bobby S]

Opamps come in 2 different form factors:
- DIP, which is what you need. It's the older type and the chips are bigger.
- SOIC, newer, smaller, surface mount type.
 
A lot of opamps come in both packages, such as AD797. The DIP version of this chip is called AD797AN
But other chips come only in SOIC form, such as the LME49990.
 
Later edit:
You should also make note of the fact you need a dual channel opamp.
AD797 is a single channel opamp. You can still make use of it, by buying 2 of them and an adapter (familiarly called browndog adapter). 

 

[PurpleAngel]

  Sorry, I'm an idiot, I meant to type HD558. I've also modded them by removing the foam on the inside, which apparently makes these equal to a HD598 now.
 
Thanks for the suggestions though, I'll check those out.
EDIT: After looking up those chips on Digikey, it looks like they aren't the type that fit into the socket on the Asus Xonar DSX. I apologize if I'm missing something, I'm still new to this.

The Xonar DSX has one dual channel Dip-8 socket.
The AD797BR and LME49990 are single channel SOIC chips.
You can take two single channel SOIC chips and solder them to a Dual SOIC to DIP-8 adapter.
There are sellers on eBay that have already soldered the dual SOIC chips to a DIP-8 adapter.
 
Here is the soldered LME49990
http://www.ebay.com/itm/DUAL-SOIC-LME49990-DIP8-ADAPTER-/190999739495?pt=US_Amplifier_Parts_Components&hash=item2c7878bc67
 
Here is the soldered AD797BR
http://www.ebay.com/itm/mod-1x-AD797BR-Dual-to-Mono-Op-amp-module-ultralow-noise-replace-a-dual-op-/261266640288?pt=LH_DefaultDomain_0&hash=item3cd4b48da0
 
Other Head-Fiers have had good luck buying from these sellers
(I bought my AD797BRs from the Audjade_Chn seller).
 
But you should check out other op-amps.
http://www.head-fi.org/t/477933/op-amp-for-asus-xonar-ds
http://www.head-fi.org/t/432749/the-opamp-thread

 

[DaWolf1205]

Thank you both so much for this info. I now have a better understanding of amp chips thanks to you.
 
I think I will try ordering that soldered LME49990 for now. I'll see how this goes, and I may update the thread later.
 
Again, thanks for the help guys!