Paul - Can't thank you enough for your thoughts and effort.
Yup, the caps and values are as you read them. I can also enlarge and publish any section you'd like. Not crazy about soldering chiclets, but what the heck….
To answer your question, the right channel noise did not appear until after installing the second DAC. As mentioned in an earlier post, there was a tiny bit of static (or leakage) in the right channel during a channel integrity test track (using E5s and wicked high volume). I had performed the op-amp mod and cap mods beforehand, while waiting for the DAC, and all was peachy. But then, I do not remember playing the cuts on which I can hear the slight distortion.
Solder joints - My first attempt did leave two cold solder joints; I reflowed these, and for the heck of it, just opened the unit and reflowed pin 10. Additionally, I've ohm'd out the connections and viewed through ~15x magnification. I do hope that in resoldering I did not overheat anything. But then, if I had, I assume that it would be very obvious.
In the original Turbo Thread, PeterR wrote about a possible rewire of the DAC that seems related to your thoughts. Here it is, followed by the submitted graphic:
"In the D25, the DAC works in Dual Channel mode, i.e. the chip handles left and right channel alternately and the outputs aren't in phase. By using a second DAC, it is possible to use them in Single Channel mode, so that each chip is dedicated to one stereo channel, giving in phase output. To achieve this, you would have to connect the second DAC a little differently than mechanoplastik describes. As far as I think to have understood, it would need to look like below (modified detail from the D25 schematic, see toro_bull's thread - second DAC in red, additional connections and cuts in blue)."
I'd have to feel confident that it would be the best design change, before cutting traces, but in conjunction with additional coupling caps, this might elevate this mod to the next level. Again, as is, it's pretty damn amazing.
Again, my sincere thanks!
Dave
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