[jude]

One of the DACs I'm using has two LT1364's in the analog output stage. Can I safely do a direct replacement of those LT1364's with OPA627's?

 

[MisterX]

Other then the fact that the LT1364 is a dual opamp and the OPA627 is a single channel opamp.... yea, a OPA627 can be considered a drop in replacement in most cases.

 

[tangent]

On paper, the LT1364 looks like a much better chip for the job. Not that the OPA627s would do badly there, just that they're not cable drivers, where the LT1364 is. A pair of OPA627s on BrownDog adapters would probably sound a lot different, so it's worth trying.

 

[jude]

Thanks, fellas.

 

[Edwood]

If you are feeling braver, there is always the option to bypass the analog output stage altogether. But that would depend on the DAC chip. Also, you should be careful of DC offset. But sometimes if can give you amazing results.

-Ed

 

[doobooloo]

Quote:

Originally Posted by Edwood If you are feeling braver, there is always the option to bypass the analog output stage altogether. But that would depend on the DAC chip. Also, you should be careful of DC offset. But sometimes if can give you amazing results. -Ed

Just bypassing the opamp won't have any effect on DC, right?

Don't most DACs have some sort of a capacitor-ed output stage that blocks DC, and removing that is what would cause DC offset problems?

i would hate to realize that my opamp-bypassed OptoPlay could have been producing DC offset all this time into my Etys and Senns while my PPA was running with bass boost!

 

[Iron_Dreamer]

Wow that LT1364 has some great stats, now you've got me pondering whether to use it on my replacement EMU when I get it. What about the sound of the DAC don't you like that you think will be fixed by changing the opamps, jude?

 

[jude]

Quote:

Originally Posted by Iron_Dreamer Wow that LT1364 has some great stats, now you've got me pondering whether to use it on my replacement EMU when I get it. What about the sound of the DAC don't you like that you think will be fixed by changing the opamps, jude?

Actually, I love the sound of the DAC. But a plug-and-play option to change it, just to see what the results might be, seemed a fun thing to explore.

After reading this thread though (single opamp versus dual opamp, cable driver, non-cable-driver), I'm most inclined at this point to leave it alone. But, before I go away completely on this....

....tangent, you said: Quote:

Originally Posted by tangent A pair of OPA627s on BrownDog adapters would probably sound a lot different, so it's worth trying.

Pardon my ignorance, but would a Browndog-adapted OPA627 perform differently than the direct-plug-in kind of OPA627? (Please pardon my lack of techno-speak, but I'm a DIY ignoramus.)

 

[Iron_Dreamer]

Hey jude (like you haven't heard that a trillion times already, but what the hell it's too fun to write), the browndog adapters would be needed, depending upon the chips you are replacing. If they are DIP then an adapter is needed to go from two-channel to dual single-channel. If it's SOIC then the adapter is similarly needed, along with a socket to hold your adapterized opamps.

 

[puppyslugg]

Jude,

There is enough of a sound difference between the lt1364 and opa627, that is would be worth giving it a shot, IMO. You may prefer the opa627.