opamp substitution ----> Which one?

Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.
Also consider the AD8066.

I swapped my opa2604 for those chips. Because the are only available in SMD-package you need browndog adapter boards.
I find the AD's have a much richer mid and high frequency, than the OPA. Furthermore the bass is very fast and I think due to its speed the sound-image has more depth.
Using this opamp and letting it perform requires special consideration for its V+ and V- as well as the grounding. I use 1nf prop caps from V+ to gnd and V- to gnd.
The max voltage according to teh datasheet is 13V, however I use them at 16V without any problems.

Henk
 
Yeah, AD8066 or AD8620 are a good choice, but I've heard from a lot of people that they may be used <+/-12V power supply ... after that it could be a non-predictable result. In one situation they work fine, and in another one - produce more distortions.
Level of mid and high frequencies depends of the used DACs as well, I have more then enough of them in the DF1706->PCM1704-OPA627->OPA2134-OPA2134->OPA2134 audio signal path (all OPA, as you can see).
I didn't notice any difference in the level of highs and mids between OPA627 and AD843K, the first one was just a bit "softer" and "warmer", I guess it is because of the lower level of amplified input voltage noise (4.5 vs 19) as the level of THD in both op amps at 10kHz is almost the same (lower in OPA627 in between1 kHz and 10kHz) ...
I compared both for LFE signals as well, AK843 has more "punchy" bass, but I personally still prefer the "flowing" bass, produced by OPA627 ... I would not say that "punchy" is more accurate ... the booms are more or less the same, but you cannot hear that much in between them in comparison with OPA627 ...
And I don't like OPA2604 at all :)
 
In the past, whenever I've replaced a 072, 4558, 4570, or 5532 in a DAC, CD Player, or Phono Stage, with something like a 2132P, the results have always been positive; the music sounds less sluggish, less murky, and comes across with better pitch definition and articulation in the notes. Results may vary with implementation in design (which may be true of the former chips as well), but, I've found the 2604 sounds a bit harsh when compared to the 2132. Try different ones and see what sounds best to you.

My present DAC had many key components changed, and the 132PAs were changed to 627BBs. The results were impressive enough that I'm considering trying out two 627s for every 2132 I have in other components. But, because the entire analogue circuit was reworked, I cannot attribute all the benefits to the chips... but, it'll still be fun to try in my other components when I have time.
 
Status
This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.