[3x331m]

I've upgraded my RKV II with OPA637, and really like the new sound. However, I wonder how the RKV II work with other opamps.

RKV owners, besides the stock opamps, what other opamps have you used with the RKV II ? Please share your experiences.

 

[3x331m]

Has anyone used OPA627's with the RKV ?

 

[majkel]

The OPA627 is darker and less lively than the OPA637. Will it work for you? You can try AD825 (SOIC only) if you haven't already done so. One of my favourites.

 

[3x331m]

Quote:

Originally Posted by majkel /img/forum/go_quote.gif The OPA627 is darker and less lively than the OPA637. Will it work for you? You can try AD825 (SOIC only) if you haven't already done so. One of my favourites.

I'm using the OPA637, and thinking about the OPA627.

Do you have to add the 68pf cap if you use OPA627 or AD825 ?

 

[majkel]

Nope, OPA627 and AD825 are unity gain stable, so if the OPA637 works well, then both OPA627 and AD825 will surely do. Actually it's best to try because even these op-amps may get unstable.

 

[3x331m]

Quote:

Originally Posted by majkel /img/forum/go_quote.gif Nope, OPA627 and AD825 are unity gain stable, so if the OPA637 works well, then both OPA627 and AD825 will surely do. Actually it's best to try because even these op-amps may get unstable.

I've tried OPA637 and OPA627. However, if I don't have the addition of the cap, I'd have problem with loud pops and crackles on one channel. I guess that it's not stable without the additional cap.

Did you actually have the AD825 installed on the RKV II ?

 

[majkel]

Unfortunately I don't own RKV.

I just left a general remark on OPA627 compared to OPA637. If you need to compensate, try to go as low with the capacitance as possible. What was the original op-amp?

 

[3x331m]

Quote:

Originally Posted by majkel /img/forum/go_quote.gif Unfortunately I don't own RKV. I just left a general remark on OPA627 compared to OPA637. If you need to compensate, try to go as low with the capacitance as possible. What was the original op-amp?

Somehow, I prefer the OPA627. I found them more quiet than the OPA637 in the RKV.

 

[Sugano-san]

Quote:

Originally Posted by 3x331m /img/forum/go_quote.gif Has anyone used OPA627's with the RKV ?

I have.

I was the one who came up with the idea of replacing the Opamps in the RKV and I worked on the realisation of this idea with Mr. Becker, the designer and manufacturer of the RKV.

I can't say it's a huge sonic difference whether you use the 637 or the 627. If it's safer, why not use the 627?

Best

 

[3x331m]

Quote:

Originally Posted by Sugano-san /img/forum/go_quote.gif I have. I was the one who came up with the idea of replacing the Opamps in the RKV and I worked on the realisation of this idea with Mr. Becker, the designer and manufacturer of the RKV. I can't say it's a huge sonic difference whether you use the 637 or the 627. If it's safer, why not use the 627? Best

Yes, I've learned about the opamps upgrade from your posts, but they were gone after the crash. I've tried the 637 and 627, and wonder if any one has found a better opamp for the RKV ?