Question: I want a music editing tool that can detect tempo, key, and chord progression, and also provide MIDI files, do you know of any?

If you want a more general-purpose music editing tool that can also figure out tempo, key and chord progression, that can export MIDI files and that's very flexible, Fadr is worth a look. This web-based tool offers a collection of AI-based tools, including a key/tempo/chords detector, stem extractor, and remix generator. You can upload songs and extract vocals, bass, drums and melodies as audio and MIDI files. Fadr offers two tiers of service: Fadr Basic, which is free forever and offers basic technology, and Fadr Plus, which adds features like the ability to separate individual drum and melody stem for $10 per month or $100 per year.

Another good option is ChordAI, which is geared specifically for identifying chords and beats in any song. Using deep learning technology, it can accept input from YouTube, SoundCloud, audio files and even your own device's microphone. ChordAI can identify beats and downbeats, infer key based on detected chords, and separate instruments into four stems and convert audio to MIDI. It's available in a free version that can be upgraded, so it's good for musicians and music fans.

For a more specialized tool, Samplab is an AI-based polyphonic audio sample editing tool geared for music producers and DJs. It lets you edit and manipulate audio samples, identify and edit chords with the ability to export as MIDI files, and adjust tempo and key for seamless sample blending. Samplab is available as a VST3 and AU plugin or desktop app. It's available in both free and premium versions, so you can customize it to your needs.

Last, WavTool is a web-based music production tool that uses generative AI to help you get where you want to go. It includes features like a multi-modal music chatbot, MIDI continuation, stem separation, and an audio-to-MIDI converter. With a customizable interface and support for VST & AU plugins, WavTool is good for musicians of all skill levels, and it's got a powerful set of tools for music production, editing and export.