If you are going to tell someone else they lack experience
and are only capable of "reading" it is probably best not to follow
that up by quoting someone else and using none of your own words to attempt to
prove a point. Even worse, is quoting someone else, who themselves quotes
someone else to prove their point ... but not really, they just provided a link
to an article.
Charlie was a character, but unfortunately, the posts you
link while having some wisdom, are also lacking. The article linked
to written by Barrie Gilbert at ADI does discuss slew rate limiting and other
potential issues related to I-V implementations and virtual grounds using
analog op-amps. However, that issue is typically more a concern with high
speed, high bandwidth DACs, of which audio DACs rarely are these days with much
of the analog inside. Of course, the simple fact that many op-amps for audio
are specified in this condition, not to mention that a simple distortion
measurement on the completed product will reveal if this is an issue in the
completed design. When one links to an article, it is probably best if
one understands it. I am not sure Charlie did. Discrete components are not a
panacea either. Integrated devices allow semiconductor component matching not
possible in discrete devices, much lower parasitic values, and often enable
circuit complexity (in a good way) that discrete devices do not
allow. In Charlie's rant on China, and LKS, he just comes across to
someone experienced as "angry". Absolutely there can be issues in
assembly in China, but his "analysis" of LKS based on a flawed photo
review does nothing for credibility. The pins on the DAC are not bent.
Simply zooming in would show that the PCB pads have staggered solder mask foot
print lengths which zoomed out makes the pins look bent. The black solder mask
is obviously for looks. Picking on "Chinese" PCB mount heat sinks?
That removes any sense of credibility from his writing.
Oh DAC versus speakers? Bluesound 2i is good, but just
that. There are better cheaper units. Something just is wrong with the sound of
it. Sounds like you have good speakers so an upgrade is likely worth it there,
but realistically, for most audiophiles, and I would include the vast majority
at almost any spend on their system, the speakers in combination with the room
are the limiting factor. It is one of the primary reasons why audiophiles are
always swapping out components. If you don't fix the basics, then you are never
going to be happy with the sound. It will never sound right. The best analogy I
can give is the difference between a professional photographer with a point and
shoot camera, and a rank amateur with a top of the line DSLR. Sure, you zoom
in, and those images on the DSLR will have lots of resolution, but the composition
is awful, the lighting is poor, and the subject matter uninteresting. The
images from the point and shoot won't have the resolution, and will have higher
noise, but will be far more visually pleasing because the most important things
w.r.t. what pleases people in an image will be far better. Everything does not
matter equally in audio reproduction. I would rather listen to 320kbps MP3 on a
really well acoustically implemented system versus 24/192 on an expensive but
acoustically poor system. Sure I will recognize the limitation of the MP3
files, but overall it will be much better.