So when I talk about structure (and I know minimal about structure) those will more than likely be factual however otherwise it is opinion.
January 1st 2013 - SNSD Releases "I Got a Boy"
To get my two cents in I have to say that I love the song. However at first I did not understand what the hell SM were thinking when they gave the biggest and most influential girl group in all of k-pop, "I Got a Boy." I… just felt like "what the fuck" however after listening to it a few (a lot of times) I came to like the song a lot. And it turns out I liked it so that it was #3 on my favorite songs of 2013 list (no regrets what so ever.)
July 3rd 2014 - F(x) Releases "Red Light"
At first I was utterly disgusted in SM. However while IGAB took like 12+ listens for me to love it, this took only 3 and I was singing along to it and love practically everything about it. That should say a lot about which song I like more. IGAB is definitely the more sweeter epic of song and videos, being poppy and colorful. However F(x) are hands more badass and empowering than IGAB with the more dark and creepy theme of the video and the more loose dance moves. However I feel as if SM switched F(x) stylist with SNSD's because the IGAB clothing is something F(x) would wear over SNSD. But anyway this is not a fashion post.
Now if you're comparing the songs themselves, opinions fly left and right and that's okay with me. However people are saying the songs are identical, which I highly agree with and all of that has to do with structure. I'll look at them both. I put the members who are singing during which part in parenthesis so you'll know which parts I'm talking about.)
I Got a Boy's Structure (From Somebody Limited On Musical Structure)
- Rap Intro Verse (Sooyoung and Yuri)
- First Verse (Tiffany and Jessica (intro) Taeyeon, Seohyun, Sunny and Jessica.)
- Bridge to chorus/mini chorus (All)
- Crazed BPM-change + IGAB chorus (All)
- Second verse (Taeyeon, Sunny, Yoona, and Hyoyeon.)
- Mini chorus (Yuri and Sooyoung)
- Mini verse (Seohyun and Tiffany)
- Mini chorus (All)
- BPM change and with some diva vocal breakdown (Tiffany and Taeyeon + 140 by Jess)
- BPM IGAB chorus (All)
- Bridge (Jessica and Seohyun)
- Final chorus (All)
Red Light's Structure (From Somebody Limited On Musical Structure)
- First Verse (Krystal, Sulli, Luna, and Victoria)
- Bridge to chorus (Krystal)
- Electronica Chorus (All)
- Second verse (Luna, Amber, Krystal, and Victoria)
- Bridge to chorus (Luna)
- Electronica Chorus (All)
- Bridge (Krystal, Amber, and Luna)
- Final Chorus (All)
You can see there that the songs are practically two completely different structures. Especially in this point of view. F(x)'s musical structure is pretty damn traditional here while SNSD's is highly off. I'm not saying one song is better than the other, because everyone has different opinions on the songs and of course some people will like IGAB over RL and vice versa and that is 100% fine. I'm just putting in my two cents on why I think the songs are not identical in any way aside from mashing songs. (And I really don't want to do that sense F(x) only mixed together two songs.) I honestly love both but I honestly like "Red Light" more. So there you go, my bizarre music taste.