This MIDI pack was originally conceived as a full replacement for the soundtrack of The Ultimate Doom, including unique tracks for all 36 maps. The project was worked on from March 27th to July 4th, 2021 on the Doomworld forums, with the express intent of releasing under the CC-BY-SA license. A good variety of tracks are included, but most fall within what you would expect from MIDIs created for Doom maps - a mix of ambient suspense tracks and fast-paced action tracks, with lots of synths and electric guitar. I suggest listening to the previews to get an idea of the style.

Previews:

1. Sampler containing parts of: (1) Bloo - Stricken Commission, (2) Bloo - Trouble in Sight, (3) Myrgharok - Escaping the Darkness, (4) TrialD - Pagliacci's Going to Town, (5) ZeMystic - Rat Men's Station, (6) Cammy - Cookie Fangs, (7) Peccatum Mihzamiz - Eclectic Death, (8) NeilJohnRips - Siege Mentality, (9) Myrgharok - On a Sea of Lava, (10) Sego - A Compact Hell, (11) Lee Jackson - Ant Farm Melee, and (12) Myrgharok - The Eternal Emptiness
2. Lippeth - You're Winner
3. Myrgharok - Halls of Wandering Spirits
4. Xulgonoth - A Search for the Soul
5. Lee Jackson - Vitamin B6
6. MegaSphere and Cammy - NM100S Pistol Start or Perish

The main version of this pack includes three tracks that are remixes of copyrighted songs; they have been removed here to create a version of the pack that is safe to distribute under the CC-BY-SA. Thus you may use these MIDIs in any project that requires them, so long as you follow the terms of the license.

Due to issues related to file size, the files have been split across three ZIPs. ultimidi-oga-midis.zip includes the MIDI files. ultimidi-oga-e1-2.zip includes the OGG files (recorded using a Roland SC-88) for the soundtrack of episodes 1 and 2. ultimidi-oga-e3-4-extra.zip contains the rest of the OGG files.

Includes MIDIs by: Bloo; Cammy; Chilpillwill; Ivan Stanton (that's me); Keagan Dunn; Lee Jackson, ASCAP (yes, that Lee Jackson); Lippeth; Manniacc; McJerb; MegaSphere; MFG38; Myrgharok; NeilJohnRips; Leonardo Silva (Palitoman); Peccatum Mihzamiz; Sego; STILES; TrialD; Xulgonoth; and ZeMystic. Audio recorded by DCG Retrowave using a Roland SC-88.

This MIDI Pack on other sites:
The Internet Archive
Doomworld forums
/idgames Archive
Bandcamp
YouTube