[raoultrifan]

The BUF634 need to be inside the loops of the opamp, otherwise will not be stable. This will completely modify the amplifier and you might want to rename it.

 

[raoultrifan]

Schematic could be identical with LME49720/LME49600 amplifier design from TI datasheet; I've used it in the past with LME49720/BUF634 with success. The BUF634 were DIP8 with heatsinks applied on top.

However, https://www.by-rutgers.nl/HeadPhoneAmp.html could be also a good one.

Good luck and keep us posted.

 

[FritzS]

@raoultrifan
I own an older Solo and a mod WNA MKII too. Now Jan Meier have loan me a Corda -ff (1) for two weeks (and to present it on the Vienna head-fi meeting). Jan use AD797 and BUF634. I had two AD797 in my stock, so I put them into my WNA instead of OPA627. This put the WNA a bit closer to Corda -ff (but not the same performance).
I think about some mods and to buy an headphone amp (like Corda) too.

As SOIC coming, I don't like to make some self with this. WNA MKII was my last project, only I changed OPAs in WNA or Solo.

You know about this site:
http://www.blue-danube.at/hifi/wna-main.php

(1)
http://www.meier-audio.homepage.t-online.de/classic.htm

 

[bsoplinger]

I ordered 2 of those Opa1611 modules. Very nice opamp anyway but I am captivated by these modules. For the price these are a steal... Oh and the underside has LED's. Bonus!

I'd want the OPA1611AID to use in a dual channel item like the Xduoo XD-05, correct?

 

[imran27]

I'd want the OPA1611AID to use in a dual channel item like the Xduoo XD-05, correct?

Why do you want OPA1611? XD-05 by default comes with OPA1612 which is a dual version of OPA1611 (Or OPA1611 is the single version of OPA1612 whichever way you want to look at it)

 

[skwoodwiva]

I bought a Cmoy from BSG who installed an Opa 2227 and, for a few dollars more, sent me an LRM4562. After that, I got so excited about opamp rolling that I went through Ebay (bad idea), Digikey and AD for more. I've tested the 627BP, AD8599, AD8066, AD797, Opa27, AD823, AD825 and a few more. For single opamps, I went through Cimarron Technologies to order Browndog Adapters.

I this anybody's favorite also?

 

[bsoplinger]

Why do you want OPA1611? XD-05 by default comes with OPA1612 which is a dual version of OPA1611 (Or OPA1611 is the single version of OPA1612 whichever way you want to look at it)

Umm, well actually I was thinking more of using it in the little bear tube amp actually but XD-05 was shorter to write and I figured that more people would be aware of the it versus the little bear since the whole changing an opamp process is new to me. I didn't really realize exactly what the XD-05 came with by default. That actually makes getting it a better purchase because I could just move the OPA1612 from the XD-05 to the little bear and get something nicer to try in the Xduoo XD-05.

 

[bsoplinger]

I this anybody's favorite also?

Out of curiosity, which opamp does the word this mean in your question?

 

[raoultrifan]

Usually op-amps could be "favorite" based on the stage it is used for. For me the list is not big:
- I/V conversion: AD797, MUSES01 and 8920, also AD8599
- LowPassFilter: BURSON SS V6 Classic, MUSES02, MUSES8820, LME49720 (also AD797 if singles are required)
- VoltageAmplificationStage: BURSON SS V6 Classic, OPA1652, LME49720, OPA2132
- Output buffer: BURSON SS V6 Classic, MUSES02, MUSES8820, LME49720

However, depending on the configuration and designed used some other opamps could be recommended. If in doubts, then LME49720/LM4562/NE5532 could be a good match.

Now speaking about Xduoo XD-05, I wouldn't change any opamps in there, as the OPA1612 is the recommended one for AK4490; also, it's specs are top of the line.

 

[Rroff]

Have to say I'm not a big fan of some of the big old favourites like the AD797, OPA627, etc. not that there is anything wrong with them as such just the sound isn't for me. AD8066 is a long time favourite but not an easy one to get the best results with (its performance can be significantly enhanced with external capacitors).

These days OPA1612 features in a lot of my usage though getting the itch to explore a few of the newer options.

 

[raoultrifan]

AD797 (BJT-input) and AD8599 (BJT-input) are extremely low noise opamps: 0.9nV/√Hz at 1 kHz and 1.1nV/√Hz at 1 kHz, so for really low-noise applications worth trying.
I'm glad OPA1612 exists, as it's also a very low-noise opamp too: 1.1nV/√Hz at 1 kHz.

Fell free to try 4.5nV/√Hz at 1 kHz in I/V or LPF or VAS stages vs. 0.9nV/√Hz at 1 kHz and you'l realize yourself the background noise difference with sensitive cans or with proper measurement equipment.

 

[skwoodwiva]

Out of curiosity, which opamp does the word this mean in your question?

You seem to lean to the LRM4562 yet opa is close?
1st line...
These will go ob my Krk boards.
https://www.head-fi.org/threads/a-krk-woody-tower-fun.876953/

 

[FritzS]

AD797 (FET-input) and AD8599 (BJT-input) are extremely low noise opamps: 0.9nV/√Hz at 1 kHz and 1.1nV/√Hz at 1 kHz, so for really low-noise applications worth trying.

AD797 is an BJT-input, please see page 11
http://www.analog.com/media/en/technical-documentation/data-sheets/AD797.pdf

AD8599 seems an BJT too
http://www.analog.com/media/en/technical-documentation/data-sheets/AD8599-EP.pdf

AD797 does a better work as OPA627 or Supreme Sound Opamp V5 in my WNA MKII
This I had tested too LM6171, AD843, AD847, LT1056, LT1022, OPA602, TLE2071.

 

[raoultrifan]

Thank you FritzS, I had modified my previous post.

 

[Rroff]

You seem to lean to the LRM4562 yet opa is close?
1st line...
These will go ob my Krk boards.
https://www.head-fi.org/threads/a-krk-woody-tower-fun.876953/

LM4562 is pretty decent - lots of detail, fairly low noise and handles audio like loads well on the down side it has a touch of cold and brittleness to the sound and is quite easily upset by PSU noise - in my experience you need to pay attention more to trace routing and shielding more than some other opamps to get good results in that respect - while stuff like the OPA1612 seem far more resilient to stray EMI/RF and PSU noise etc.