[Exophaze]

That looks promising! Lucky i've been busy so i haven't modded my a28 yet. Seeing this, i might solder in adapters to make opamp switching easier and do the capacitor mod the same day unless that would be problematic with the sonic opamps. Would be nice if b0bb could give his opinion on the capacitor mod too

@Villy, your novel on the primes inspired me so when i found a pair at a decent price for sale, i immediately sent the guy an offer and hopefully he accepts!

 

[Villy]

I did solder adapters, you cans see them on my pics, with the long wire legs. You should get a set like those otherwise won't be able to fit in the opamps, the Sonics especially. Go ahead with it, it's one upgrade that's worth 100%. As for opamp rolling; b0bb had remarks on another thread why the Sonics may be the best choice for A28. Nevertheless, if I had another set of opamps handy I'll most certainly roll 'em.

 

[Villy]

Here's the post I mentioned, you'll find the 994enh opamp/A28 matchup comments somewhere in the middle: 
http://www.head-fi.org/t/705654/discrete-vs-ic-opamp-rolling-in-a-marantz-cd80

 

[b0bb]

That looks promising! Lucky i've been busy so i haven't modded my a28 yet. Seeing this, i might solder in adapters to make opamp switching easier and do the capacitor mod the same day unless that would be problematic with the sonic opamps. Would be nice if b0bb could give his opinion on the capacitor mod too

Yulong has something similar to the 10uF cap mod on the A28's board.
 
This is C25 and C26 in Villy's picture

 

[Villy]

Ah, very good, one thing scratched off the list (too bad it was the easiest possible mod that involves soldering).

 

[Villy]

For those of us sizing up an Ether - just heard of it and immediately looked it up, and yes E model was unveiled at SoCal's CanJam, that is E as in Electrostatic, yes

and apparently has been the hit of the meet, supposedly better sounding than the present Ethers and still not finalized yet

hmmm, ok, I'll get an Ether one way or another, open or closed, but ain't buying static amp

 

[Exophaze]

Yeah... electrostatics... im neither ready nor willing to go that route (yet).

 

[Villy]

Hi b0bb, I wonder if you could give your opinion on another Yulong related subject.
 
I purchased D200 to use it at the office, the DAC is very good actually and the integrated amp is just ok which is understandable for an add-on function. Like its big bro DA8 though, D200 can drive balanced headphones from the balanced outs and that is how I intend to use it (haven't tried it yet, waiting on a set of XLRs to build me adapter cable). Or I might eventually get another balanced amp, will see. In the meantime, I popped it open of course to see what's inside - it has a pair of OP275 which Yulong says serve as low pass filters. I wonder what your opinion is on whether it is worth replacing them with discrete. I'm not even sure I will actually do it given that they have SOIC interface (oh boy, aren't these pins tiny!), but it is bugging me and I can't just sit around not knowing if it is doable or not 

 
Regards

 
Edit: doable in the sense of worth doing it from sound perspective.

 

[solblack]

  Hi b0bb, I wonder if you could give your opinion on another Yulong related subject.
 
I purchased D200 to use it at the office, the DAC is very good actually and the integrated amp is just ok which is understandable for an add-on function. Like its big bro DA8 though, D200 can drive balanced headphones from the balanced outs and that is how I intend to use it (haven't tried it yet, waiting on a set of XLRs to build me adapter cable). Or I might eventually get another balanced amp, will see. In the meantime, I popped it open of course to see what's inside - it has a pair of OP275 which Yulong says serve as low pass filters. I wonder what your opinion is on whether it is worth replacing them with discrete. I'm not even sure I will actually do it given that they have SOIC interface (oh boy, aren't these pins tiny!), but it is bugging me and I can't just sit around not knowing if it is doable or not 

 
Regards

 
Edit: doable in the sense of worth doing it from sound perspective.

Read the threads its doable

 

[Villy]

I scanned all the threads and didn't find any references, the D200 and DA8 threads that is, hence the reason for asking the question. With that said, apparently I missed it or didn't even look at the right place - if I profess stupidity

will it earn me a hint where the key might be hidden

and in the meantime I keep on looking ....

 

[b0bb]

  Hi b0bb, I wonder if you could give your opinion on another Yulong related subject.
 
I purchased D200 to use it at the office, the DAC is very good actually and the integrated amp is just ok which is understandable for an add-on function. Like its big bro DA8 though, D200 can drive balanced headphones from the balanced outs and that is how I intend to use it (haven't tried it yet, waiting on a set of XLRs to build me adapter cable). Or I might eventually get another balanced amp, will see. In the meantime, I popped it open of course to see what's inside - it has a pair of OP275 which Yulong says serve as low pass filters. I wonder what your opinion is on whether it is worth replacing them with discrete. I'm not even sure I will actually do it given that they have SOIC interface (oh boy, aren't these pins tiny!), but it is bugging me and I can't just sit around not knowing if it is doable or not 

 
Regards

 
Edit: doable in the sense of worth doing it from sound perspective.

Doable but not recommended  U20 and U7 in the picture will run into clearance problems and the the caps (C79, C69) will have to be relocated.
Removal of SOIC requires a hot-air wand in order to minimize board damage, might be difficult depending on the skill level of the technician.
 
You will need an adapter similar to this.

http://www.logicalsys.com/painfo-vpasp-vb.asp?adapter=pa-dso-0803-d250-08/2
 
Yulong used ceramic caps, this limits potential sound quality improvements.
 
I would much preferred it, if Yulong had used plastic film caps like PPS or polypropylene like the ones they used on the A28.
 
You will get better results by replacing the 3 voltage regulators with ones from Belleson or Sparko, that is what I did on my DA8 before moving on to the LKS.

 

[Villy]

Got it, thx very much! I am definitely not messing with the opamps then, and will heed your advice on the regulators, they are goners.