Blown away with 2 speakers hifi sound!

It's great doing something upstream, or adjusting speaker position, or taking care of room acoustics and have our system sound so much better.An audiophile friend told me many years ago... "the speakers just produces the sound of the signal that they receive".  I deduced then that I can make changes upstream to improve the sound of my speakers. So after upgrading all my cords... I'm just tweeking now, as the cost to benefit is great. Some recent tweeks and adjustments that have produced magnificent results: I got a narrower acoustic panel to fit a narrow spot behind me... dampening material on case cover of CD player, SR blue fuse in CD power supply, CD mat, and speaker tow in 1/4".  My system sounded amazing before.... I am still absolutely amazed how much more incredible it sounds now... and there's still a few tweeks up my sleeve ; )

I think what made this hobby(industry) great is the shape (or shades) to approach to a sensation. I like to think of it a triangle, with different hobbyist like to push (approach) to a certain corner (direction) May it be in the sharpestest and cleanest notation digitally, or fattest and warmest reel to reel or lps, or thirdly, realism, like you were there with the music. In that triangle money change hands. Opinions going back and forth. Adding no two ears are the same now there are millions of combination. There is no right or wrong, just the direction you you want to go, or you wives(partners) allows you, or the monies to support you. Happy listening.....you will hear more when you are in a wonderful mood. 

Gongli3, in regards to connecting a DAC via the optical on your TV, doubtful. Most optical on TV’s are an input, and do not output sound. You may want to look for a DAC that has a HDMI input that can connect the DAC and TV as an input/output connection. And that would take some thought as well, as now all the sound coming out of your TV would, in all likelihood, be transmitted as 2 channel only. I’m no AV expert, so perhaps someone else could clarify. Bottom line, all sound from my TV is transmitted via HDMI, but I never listen to music via an HDMI input/output; the lone exception is when listening/watching the Berlin Philharmonic live or pre-recorded which I have a subscription to. 

I can tell you for certain that whenever I listen to any streaming service via the HDMI from the TV (if I’m being lazy or just checking something out) it’s sounds terrible vs streaming directly through my DAC and connected to my system via RCA stereo inputs. For serious listening I never stream from my TV, or CD player for that matter (which also has that capability). Perhaps a DAC/streamer would be the obvious choice.

My tv's all employ optical out to either my 2 HT receivers( family room,and living room) and a soundbar(bedroom)

Then I stand corrected.