[Shini44]

guys do i need 2x LM4562 or i should use one on the M-Stage

 

[elwappo99]

  guys do i need 2x LM4562 or i should use one on the M-Stage

 
http://www.ti.com/product/lm4562
 
Only need one. It's a dual channel opamp. 

 

[nickwin]

I've tried a couple op-amps and the changes have always been minor, and certainly nothing like what you're describing.

I don't hear that much difference between the stock op-amp and the LM4562 I have in there now.

I haven't tried the stock OP AMP but the difference between the class a opa627 I got from Tam Audio and the lm4562 was certainly not minor to my ears at all. Opa627 was warm colored and muddy IMO and had a totally different tonality than lm4562. Maybe stock is closer to lm4562?

 

[nickwin]

You could argue that two single Op Amps on an adapter may sound worse than one dual Op Amp without an adapter board.
An adapter just adds more parasitic elements to the circuit.

This is how I look at it too. It also mirrors my personal experience going from opa627 (dual) to lm4562 (single). I wouldn't mind trying this lm49710x2 though.

 

[blueangel2323]

I haven't tried the stock OP AMP but the difference between the class a opa627 I got from Tam Audio and the lm4562 was certainly not minor to my ears at all. Opa627 was warm colored and muddy IMO and had a totally different tonality than lm4562. Maybe stock is closer to lm4562?

The class A mod is indeed very warm. I think the normal opa627 might be better? And the stock is pretty close to the lm4562, with the exception of the treble.

 

[Shini44]

   
http://www.ti.com/product/lm4562
 
Only need one. It's a dual channel opamp. 

 
http://www.mouser.com/ProductDetail/Texas-Instruments/LM4562NA-NOPB/?qs=sGAEpiMZZMtCHixnSjNA6JlKxGj6zye%252bDw5UwZXQkUk%3d
 
 
same? i don't think so :/  why does they have the same code yet not the same shape? 

 

[elwappo99]

 

   
http://www.ti.com/product/lm4562
 
Only need one. It's a dual channel opamp. 

 
http://www.mouser.com/ProductDetail/Texas-Instruments/LM4562NA-NOPB/?qs=sGAEpiMZZMtCHixnSjNA6JlKxGj6zye%252bDw5UwZXQkUk%3d
 
 
same? i don't think so :/  why does they have the same code yet not the same shape? 

 
Yup, they are the same. You need the DIP8 package, which is what you have linked on mouser. 
 
The link on TI shows the SOIC package. Same identical operation, different size/shape.

 

[Shini44]

   
Yup, they are the same. You need the DIP8 package, which is what you have linked on mouser. 
 
The link on TI shows the SOIC package. Same identical operation, different size/shape.

 
is the LME48710 is a single version of the LME4562?

 

[Chodi]

   
is the LME48710 is a single version of the LME4562?

 
You should try using the search function. Here is a link that clears some of this up for you:
 
http://www.head-fi.org/t/542563/asus-essence-one-headphone-amp-dac-cebit-2011/1005

 

[proton56]

Have you chek if the schema is compatible with the LME4710, the 627 is a jfet and the LME4710 is a bipolar ?
 
You can have noise and continus courant if you put a bipolar instead a jfet...
When I buy, chips, I take several ships.
The LME49860 have been prefered to the LME49710 on several discussions (similar sound but more natural, better mid, better on the voices, more soft).
The ADA4627 have been prefered to the OPA627 on several discussions (similar sound but more defined).
My prefered are OPA211 and OPA1611 (more soft).

Good tests
Proton

 

[Xprime4]

I just tried the stock opamp since i had the amp with the 627 already installed and the difference is quite big. The stock one make the music less dynamics imo.
 
I ordered a LM4562, but until i get it i'll be putting the 627 back for sure

 

[Chodi]

  I just tried the stock opamp since i had the amp with the 627 already installed and the difference is quite big. The stock one make the music less dynamics imo.
 
I ordered a LM4562, but until i get it i'll be putting the 627 back for sure

Curious about what you are using for a dac and headphones? I agree with you in one respect; I also hear a big difference between the op627 and the stock opamp. Did you buy that op627 as a class A mod from Tam?

 

[Chris J]

Have you chek if the schema is compatible with the LME4710, the 627 is a jfet and the LME4710 is a bipolar ?

You can have noise and continus courant if you put a bipolar instead a jfet...
When I buy, chips, I take several ships.
The LME49860 have been prefered to the LME49710 on several discussions (similar sound but more natural, better mid, better on the voices, more soft).

The ADA4627 have been prefered to the OPA627 on several discussions (similar sound but more defined).

My prefered are OPA211 and OPA1611 (more soft).


Good tests
Proton

Depends, depends, depends.....

Bipolar Junction Transistors can have lower noise than JFETs.
As for the idle current, again.....it depends, could be more could be less.
A lotof guys do a Class A mod which increase the bias current on the OP627.

But you always need to confirm that any replacement Op Amp you are using has the same pin out and it Must Be Unity Gain STABLE to prevent oscillation.

 

[proton56]

Bipolar Junction Transistors can have lower noise than JFETs."
 
Depends of the resistance before the opa, depends of the schema, I had had a bad experience with the remplacment of a JFET with a Bipolar.
The noise was not realy a probleme, but the continus curent was...I have changed the resistance before the opa and it's ok, sometime we have to change the schema for the opa.

The oscillation is not the only risk, and it's can be corrected if you study the theory and the datasheet (adding caps etc..).
Some opa can remplace similar opa without any risk, we can find the right match on inernet.
Generally I think it's more safe not to inverse JFET and Bipolar, but I am not electronician...
I would just explain than rolling amp can be dangerous, and the opa are rarely at there best in a schema not made for them.
But we can experiment the sound of an opa on several schema, it's always the same nature, and we can find the sound than we prefer.
 
The matrix can be safe for a lot of opa, I don't know.

 

[Shini44]

I just swapped the stock opamp for the free LM4562 sample that I received from TI. To my ears, the first thing I noticed was that the LM4562 makes the treble more delicate. Thinner, sharper, and more defined. Actually, a better word would be crisper. It sounds very crisp. The stock opamp sounded more "diffuse" and "atmosheric" in the treble. It's a bit analogous to tighter, faster bass with sharp impact, as opposed to fatter, more resonant bass with duller impact. Except... in the treble. Sorry if I'm not expressing myself very clearly; sound is hard to describe

 

I fully agree with your description of the LM4562.
And I know what you mean, sound is hard to describe, I'm terrible when it comes to describing sound too! 

Thanks!! will comment on that too once i test this setup