ShredDB is an experimental .shred library, I removed the audio so it's pretty useless. You can find the source .psarc files here.

Song	Artist	Play	Shred	Length	Album	Year	Tuning	Uploader	Updated	Delete
Rebirth The Edge	Shade			2:45	Sengoku Rance Soundtrack	2006	D Drop C	mute	1970-01-01
Reception Fades	Rise Against			2:10	The Unraveling	2001	E Standard	mute	1970-01-01
Reclaimed Earth	Andrew Hulshult			12:07	DOOM: Eternal - The Ancient Gods Part II (Original Game Soundtrack)	2021	Custom Tuning	mute	1970-01-01
Red Hot Skull (Red Mountain 2)	Sonic Adventure			3:18	Sonic Adventure Soundtrack	1998	E Standard	mute	1970-01-01
Red Lenses	Rush			4:55	Grace Under Pressure	1984	E Standard	mute	1970-01-01
Red Like Roses	Jeff Williams			3:16	RWBY Volume 1 Soundtrack	2012	Drop D	mute	1970-01-01
Red Like Roses Part II	Jeff Williams			4:05	RWBY Volume 1 Soundtrack	2013	E Standard	mute	1970-01-01
Red Madness And My Desire	Draw the Emotional			2:38	Funny party in the Fog	2011	D Drop C	mute	1970-01-01
Red Sector A	Rush			5:18	Grace Under Pressure	1984	E Standard	mute	1970-01-01
Red Streamer Battle	Yoshito Sekigawa, Shoh Murakami, Yoshiaki Kimura, Hiroki Morisihita, Fumihiro Isobe			2:50	Paper Mario: The Origami King Original Soundtrack	2020	D Standard	mute	1970-01-01
Red to Black	Fort Minor			3:11	Unknown	2014	E Standard	mute	1970-01-01
Redeemer	Bury Tomorrow			4:35	The Union of Crowns	2012	D Drop C	mute	1970-01-01
Reeko	NOFX			3:08	Punk in Drublic	1994	E Standard	mute	1970-01-01
Refreshing Morning	Atkahiro Unisuga			2:21	The Legend of Heroes: Sen no Kiseki Original Soundtrack	2013	E Standard	mute	1970-01-01
Refugio Vital	Agora			4:57	Segundo Pasado	2001	E Standard	mute	1970-01-01