: Large "all-in-one" bundles often suffer from incorrect chord changes or antiquated MIDI styles. Many experienced users recommend curated collections like those from Norton Music or official Hal Leonard software integrations. Where to Find Song Collections
Summary
Here’s the catch: the songs themselves (melodies and lyrics) are still under copyright unless in the public domain. While chord progressions aren’t copyrightable, distributing a full “Real Book” index as playable BIAB files can cross into grey territory. The legitimate route is to buy the official RealBook add‑ons from PG Music (makers of BIAB), which offer licensed versions of hundreds of standards. However, many users share their personal transcriptions of public‑domain jazz tunes (pre‑1928) — and those can legally exceed 10,000 songs when you include traditional, folk, and early blues. band in a box real books 13000 tunes link
note that having correct chord progressions pre-loaded is "spot on" and eliminates the tedious task of manual entry. Customization: The Verdict: The Ultimate "Fake Book" Time-Saver Quality
Once you have a legitimate source of these files, here is how your practice routine transforms: Band-in-a-Box makes transposing easy
It is important to understand that PG Music does not own the copyright to the songs. They license the mechanism to display them. Consequently, they cannot ship these files with the melodies written out (due to copyright restrictions on the notes/heads).