BB OPA2604AP In shanling CD-T80 for OPA627AP?

[johnm]

Hi everyone!

Quick question - I have a Shanling CD-T80 (great player) which uses three Burr Brown OPA2604AP chips which are - conveniantly - housed in turned sockets ;-)

I just happen to have a few OPA627AP op-amps to hand, and was wondering if I can use these as a straight subtitute for the '2604s? Had a look at the date sheets (I'm no expert alas) but it appears they use different pin-configurations.

Coudl someone please confirm whether or not I can substitute OPA2604AP for the OPA627AP?

Many thanks!

- John

[Paco]

You can't use OPA627 in place of the 2604 as the 627 is a single channel opamp and the 2604 is dual. You should mount two 627 in an adapter to have a dual OPA627. I've tried both and OPA627 is much better. If the output stage isn't DC coupled, it may be a good idea to use a extreme quality cap at the output, like Mundorf Silver in Oil or Hovland.

Regards,
Paco

[jomar]

You can get the BrownDog Adapter at THIS site .

[johnm]

Thanks Jomar / Paco!

Very helpful - I'll definately order three of those Brown Dogs. Can't seem to find them in the UK though which is annoying.

Bit worried about occilations in the 627 chip as its already in a socket, and with the Brown Dog it'll then be in two sockets! Guess I'll have to just try it and see.

Cheers,

- John

[Paco]

Hi johnm,
You can find them at www.wnaudio.com
I think that they doesn't appear in the catalog, you should send an email.
I have my double OPA627 in an adapter from White Noise and it's also mounted in a socket. No stability problems at all with this opamp (the AD8066 is a different story!).

Regards.

[Anders Enquist]

I have an offer to buy 6 pcs OPA627AP opamps. Will they and the BrownDog Adapter fit in the Shanling CD-T80 without alterations? (My hope goes to johnm that you know by now ..!)

[PinkPanther-2]

I advise to use OPA627 AP (or BP) in DIL corpse instead of OPA 627 AU in SOIC corpse because of cooling problems. There are adaptors for both forms by Brown dog and all depends on place on PCB you have.

[johnm]

Hi thanks for your replies!

Yes I managed to get the brown dog adaptors a whiel back, and installed the OPA627s. I have to say however that I didn't like them in the Shanling - sounded far too clinical and th eemotional seemed stripped away from the recordings. Perhaps they needed the + and - pins pypassed or something? (Not really possible given the limited space on the brown dog converter). Lived with it for just over a month then tried some OPA2134s which sounded MUCH better (for this player at least) so have stuck with those.

I'm will be using the OPA627s in a Quad 34 rebuild I am currently doing.

Cheers!

- John

[Anders Enquist]

Thanks for sharing your insights about various opamps in the Shanling CD-T80. As so many times happens, making a difference not necessarily means improvement.
The OPA2134 seems a viable alternative since being two-channel and not very expensive. Curiously, despite better specs than the OPA2604 it costs less.
The CD-T80 is fine sounding as it is, a genuine improvement on the trusty old Audiomeca Kreatura/Elixir combo it replaced so maybe I'll just swop the valves for some RCA NOS specimens and live with it for some time.

[IndyAudi]

Quick question - I have a Shanling CD-T80 (great player) which uses three Burr Brown OPA2604AP chips which are - conveniantly - housed in turned sockets ;-)

Before you starting spending money on OPAXXX and browndogs I would suggest that you contact TI.com and ask for four samples of these and then select the best three > sound and minimum DC offset.