[covame]

I want to buy a new set of OPA627 for my HR-2, but I’m confused with which op amp I should buy because there are two types: the OPA627AP-ND and the OPA627BP-ND both come in 8-DIP package, the OPA627AP costs 18 dlls and the OPA627BP costs 26. I would appreciate it if some one can tell me the difference and which are the adequate to use with the amp. Thank you in advance for your kind assistance.

 

[Pete7]

Most apparently cannot tell the the difference in sound between the two different OPA627's. However, supposedly the OPA627BP has less DC offset making it the better choice.

 

[trose49]

Quote:

Originally Posted by Pete7 /img/forum/go_quote.gif Most apparently cannot tell the the difference in sound between the two different OPA627's. However, supposedly the OPA627BP has less DC offset making it the better choice.

Just wondering why you want to change it?

Also I believe Ray sells Op amps that are completely burned in so you dont have to wait the 200 or so hours for Burn-IN!

 

[covame]

Thanks Pete7 for the information.

Quote:

Originally Posted by trose49 /img/forum/go_quote.gif Just wondering why you want to change it? Also I believe Ray sells Op amps that are completely burned in so you dont have to wait the 200 or so hours for Burn-IN!

I asked Ray about buying op amp’s and he referred me to Digi-key.
I find that swapping op amps in the amplifier modify its sound signature in some degree; that helps me not to get used to the amp’s sound. On the other hand, I’ve encountered that I liked the LT1028 more than the AD797, I wont tell you that it’s better, it’s only a matter of personal appreciation.

 

[trose49]

Quote:

Originally Posted by covame /img/forum/go_quote.gif Thanks Pete7 for the information. I asked Ray about buying op amp’s and he referred me to Digi-key. I find that swapping op amps in the amplifier modify its sound signature in some degree; that helps me not to get used to the amp’s sound. On the other hand, I’ve encountered that I liked the LT1028 more than the AD797, I wont tell you that it’s better, it’s only a matter of personal appreciation.

What are the sound sig differences with the LT1028?

So Ray isnt selling burned in opamp anymore?

 

[covame]

The LT1028 has less bass emphasis, sweeter mids, extended high’s and has more soundstage. The AD797 have better dynamics, their bass is more prominent and has more impact, their mids are more neutrals and their highs are not as extended.
I bought my HR-2 used, maybe this is why he referred me to Digi-Key.

 

[trose49]

I tried to figure out that site. wow there are alot of 8 dip Op amps!

 

[trose49]

Quote:

Originally Posted by covame /img/forum/go_quote.gif The LT1028 has less bass emphasis, sweeter mids, extended high’s and has more soundstage. The AD797 have better dynamics, their bass is more prominent and has more impact, their mids are more neutrals and their highs are not as extended. I bought my HR-2 used, maybe this is why he referred me to Digi-Key.

I dont find the AD797 that Bass prominent. Could be the source of course Planet 2000.

Anyone know of an OPamp that sounds very close to the AD797 with slightly more low end?

 

[Welly Wu]

You need to buy two OPA627BP-ND op-amps for the HR-2. However, you can get free samples from Texas Instruments. Do a search.