[JiggaD369]

Hello everyone,
 
I want to replace the LM837 quad amp for my balanced DAC and I was able to get free samples of both OPA4134 and OPA4228 from TI. I'm no expert of electronics so is it possible to use either of those two to replace the LM837? If so, is it worthwhile to replace it OR should I look into some other quad opamp?
 
I do not have the schematic to the DAC but this is the pic. of the output of the DAC and the opamp is one of the final components on there (upper right corner).
 

 

[Avro_Arrow]

I would probably pick OPA1644.

 

[JiggaD369]

Avro,
 
Any perticular reason why that specific one over the other two?
 
Just trying to learn why. 

 

[Avro_Arrow]

OPA4228 is only stable at gain 5+, do you know what
the gain is of the circuit currently is? I don't. Better to stick
with unity gain stable...maybe the OPA4227.
 
OPA1644 is an updated version of OPA4134.
Bandwidth and slew rate are twice that of the older version.
 
There may be other options but I don't know that many quads...
 
Quote:

Avro,
 
Any perticular reason why that specific one over the other two?
 
Just trying to learn why. 

 

[JiggaD369]

Quote:

OPA4228 is only stable at gain 5+, do you know what
the gain is of the circuit currently is? I don't. Better to stick
with unity gain stable...maybe the OPA4227.
 
OPA1644 is an updated version of OPA4134.
Bandwidth and slew rate are twice that of the older version.
 
There may be other options but I don't know that many quads...
 

 

Thanks! Its always good to learn something new!
 
Since I'll be ordering a new opamp, would you suggest 4227, 1644, or something else? Cost is not a factor.

 

[Avro_Arrow]

I think I would go with the OPA1644. I have used the OPA1641
and OPA1642 and was happy with the sound and performance.
I think I have some OPA1644 laying around that I was going to
use for an Apheared 47 but I have not had a chance to build
it yet.
 
LME49740MA and AD8513ARZ look like contenders as well though
I don't have any experience with them myself. On paper, the LME49740
looks like a pretty good choice.
 
Hope that helps...
 
Edit: fixed LME part #