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
Rainy Night in Georgia	Ray Charles			6:20	Through The Eyes Of Love	1972	E Standard	mute	1970-01-01
Rainy?	Three Man Down			4:27	Single	2019	E Standard	mute	1970-01-01
Ray Ray Rain	Bettie Serveert			4:26	Lamprey	1995	E Standard	mute	1970-01-01
Re Your Brains	Jonathan Coulton			4:31	Thing a Week Two	2006	E Standard	mute	1970-01-01
Realm of Rain	A Canorous Quintet			3:34	The Only Pure Hate	1998	C# Standard	mute	1970-01-01
Refrain Boy	ALL OFF			3:36	Mob Psycho 100 ED Single	2016	Eb Standard	mute	1970-01-01
Refrain Boy -English Ver.-	ALL OFF			3:36	Mob Psycho 100 ED Single	2016	Eb Standard	mute	1970-01-01
Retaliation / Realm of Rain	A Canorous Quintet			7:58	The Only Pure Hate	1998	C# Standard	mute	1970-01-01
Rhythm of the Rain	The Cascades			2:27	Rhythm of the Rain	1962	E Standard	mute	1970-01-01
Ride The Rainbow	Axel Rudi Pell			4:56	Oceans Of Time	1998	Eb Standard	mute	1970-01-01
Rising Rainbow	Misokkasu			3:36	Shokugeki no Soma OP2 Single	2015	Drop D	mute	1970-01-01
Road Train	King Gizzard & The Lizard Wizard			4:23	Nonagon Infinity	2016	E Standard	mute	1970-01-01
Rock N' Roll Train	AC/DC			4:23	Black Ice	2008	E Standard	mute	1970-01-01
Rocky IV Training Montage	Vince Dicola			3:36	Rocky IV Soundtrack	1985	Drop D	mute	1970-01-01
Runaway Train	Geddy Lee			4:40	My Favourite Headache	2000	E Standard	mute	1970-01-01