What is my favorite song?

I think this song is one of the greatest of all time, when it comes to lyrics. It starts like this:

ELDR ESYL NSMOD FINIE OEOA WTYU KIHOA GI

HLOAK REDV CMTTL AN

What is my favorite song then?

This song is good too, but not as good as the one I'm asking about. It starts like this:

IHTM HRES SAPNH EGTNE CSNA O IN

NGTIE IHES AHEST

Or, in other words:

Night time sharpens, heightens each sensation

• It would've been a little bit harder if you excluded the second part with the solution, that pretty much gave it away (at least for me) – user14478 Sep 22 '16 at 19:05
• @LukasRotter, what about deleting second part of the code? – Yuriy S Sep 22 '16 at 19:07

Putting the letters together, we get the lines

Hello darkness, my old friend
I've come to talk with you again

from the song

"The Sound of Silence" by Simon and Garfunkel.

I found this by first examining the second half of the question, whose answer was given:

IHTM + NGTIE = NIGHTTIME;
HRES + SAPNH = SHARPENSH;
EGTNE + IHES = EIGHTENSE;
CSNA + AHEST = ACHSENSAT;
O + IN = ION.

Applying the same method to the ciphertext in the first half of the question, we find:

ELDR + HLOAK = HELLODARK;
ESYL + NSMOD = NESSMYOLD;
FINIE + REDV = FRIENDIVE;
OEOA + CMTTL = COMETOTAL;
WTYU + KIHOA = KWITHYOUA;
GI + AN = GAIN.

• @Bulldogg6404 Done. – Rand al'Thor Sep 22 '16 at 20:33
• @humn Huh, for some reason I thought it wouldn't work that way round. Fixed. – Rand al'Thor Sep 27 '16 at 1:01