Please, help me to pick the right center and surround speaker for my home theater


I have my current set up:
- Integra rdc 7
- B & K reference 200.5 
- Martin Logan Ethos ( L+ R seapker)
- I used to have Martin Logan center cinema i ( but sound not right) sold
- Definitive mythos gem for surround ( just want to upgrade new on, please recommend)
Please, help me to pick the center and surround speaker. Thanks a lot...
thongtran09
For 600 bucks you really can't go wrong with an Aerial center speaker.  For surrounds, well, not sure how much you're gonna notice an upgrade there.  Maybe some Elacs?

https://www.usaudiomart.com/details/649493190-aerial-acoustics-cc3-center-speaker/
Thanks for all the respond.
-  I will buy the martin logan motion 35xt for surround,
-  I try the martin logan center speaker esl c but the sound still not loud and clear. I still need to try another center.