[Whyifide]

Hello all, I just got the ASUS Xonar Essence ST, and I'm pleased with it, and along with my new AD700's, my musical world has been transformed. However, I'd like to be introduced to this new world of possibilities that I've been given by ASUS, the ability to easily swap OPAMPs without soldering.

What do opamps do? What are the stock opamps on the essence st and their qualities? How many different combinations can I make? What are the different opamps, where can I get them, and how much do they cost?

Hopefully I'll be able to make up for any missing quality in my headphones with opamps!

Thanks a bunch ahead of time.

 

[leeperry]

never swap a dual opamp for a single, and always check several times that you didn't insert them upside down...these are the two most important rules IMO.

about differences? the best chips have been described here: http://www.head-fi.org/forums/f6/aud...-v-2-a-397691/

you can use single opamps on the STX using adapters from Cimarron Technology, Inc.

 

[Currawong]

You are probably aware that the transistor replaced the vacuum tube for amplification many decades ago. Well, an OPAMP is an IC (Integrated Circuit) that replaces a bunch of transistors and other components. It allows an amplifier to conveniently fit on something like a sound card in a computer.

Commonly, OPAMPs come in a variety of formats, but the most common is known as "DIP8", which is a small rectangle with 8 pins. This is the form which, if plugged into a socket rather than soldered, can be easily replaced. Confusingly though, OPAMPs come in two varieties: Single channel and dual channel. Since stereo sound has two channels, depending on what you're using, you will either need two singles or one dual. Some OPAMPs have single and dual versions available, with slightly different model numbers.

Any DAC (sound card in your case) has a circuit of some description to amplify the tiny signals that come from the DA chip to line level or a level suitable for headphones. This circuit is actually what gives a DAC its "sound" -- really the resulting tonal balance. The quality of the OPAMP, as it is the amplification circuit, will have the most significant effect on the overall sound and sound quality, though in something like a sound card inside a computer, there's a limit to what is possible to achieve with only a small space for everything to fit.

OPAMPs can be purchased from big electronics parts suppliers online, such as Mouser and Digikey, and sometimes samples can be ordered for cheap or free from the makers: Texas Instruments and Linear Technology.

 

[ROBSCIX]

Quote:

Originally Posted by Whyifide /img/forum/go_quote.gif Hello all, I just got the ASUS Xonar Essence ST, and I'm pleased with it, and along with my new AD700's, my musical world has been transformed. However, I'd like to be introduced to this new world of possibilities that I've been given by ASUS, the ability to easily swap OPAMPs without soldering. What do opamps do? What are the stock opamps on the essence st and their qualities? How many different combinations can I make? What are the different opamps, where can I get them, and how much do they cost? Hopefully I'll be able to make up for any missing quality in my headphones with opamps! Thanks a bunch ahead of time.

I would suggest you do some real research. Read up on the various subjects and verify what you read. Here, there is a opamp thread here that can help with question if you have them: Opamp thread

 

[Whyifide]

Leeperry, Currawong, ROBSCIX - Thanks a ton guys. You've pointed me in the right direction of good and useful information. I really appreciate it.

 

[ROBSCIX]

No problem, If you have any questions ask.

 

[Iniamyen]

Tangent's guide was also helpful for me...

Notes on Audio Op-Amps

 

[hawkhead]

Notes on Audio Op-Amps

 

[Whyifide]

Quote:

Originally Posted by ROBSCIX /img/forum/go_quote.gif No problem, If you have any questions ask.

Just one question atm: where can I get an adapter if I want to use two single channel opamps

 

[BryanP]

Here's a primer on it for the ones who don't want to read datasheets:
Introduction : OPERATIONAL AMPLIFIERS

You can pretty much get a somewhat "forward" overview of different op amps without all the theory... but with still all the necessary high-level information IMO. It isn't pointed towards audio though, but once you get an idea of a general op amp, then asking audio related questions shouldn't be too far off the plate.

 

[ROBSCIX]

Quote:

Originally Posted by Whyifide /img/forum/go_quote.gif Just one question atm: where can I get an adapter if I want to use two single channel opamps

There are many places that have adapters. A popular adapters maker around here is: Brown Dog
I am not sure if you mean single channel surface mount chips(SOIC8) or single channel through hole components(Dip8), this place has both.

 

[Applesnapple]

I need some help folks. Related to this thread, I purchased a xonar st off of flea bay. The gentleman included several different assorted opamps with the card. Few of them matched, so I found a pair that did and swapped out the mismatched pair on the card. The chips were difficult to read, but I was pretty sure they were LME49720's that I'd heard quite a bit about. I placed the card in my pc, booted, and tried to play some music through foobar. No sound. The card was properly selected, and foobar didn't complain, but still no sound. Upon further review, and use of an LED flashlight, I've determined that the opamps I placed in I / V were LME49710's aka single channel. So..what have I done? Have I fried the card? Would this explain the lack of sound from both speakers and headphones? Can I fix my error by replacing the 49710's with the JRC 2114d's that he also included? Help!

 

[Head Injury]

Did you check to make sure the card ever worked? I would never buy a computer component from a flea market without a demonstration that it works.

 

[Applesnapple]

Quote:

Did you check to make sure the card ever worked? I would never buy a computer component from a flea market without a demonstration that it works.

Unfortunately, I didn't. The seller is in Jersey, I'm in California. Bottom line though...would doing what I described fry the device, or simply cause it to not function?

 

[Apocalypsee]

Quote:

Unfortunately, I didn't. The seller is in Jersey, I'm in California. Bottom line though...would doing what I described fry the device, or simply cause it to not function?

If you use single channel opamp on the place of dual channel ones the most likely that would happen is you can kiss those opamp goodbye. But its likely your card survives, so put those stock 2114D back and it should work. This is based on my experience because I did this silly mistake before, it have no sound but put back the right opamp it worked again