I have an old keyboard with a 1/4" output. Is there any way, any device, that can convert the audio signal coming out of the keyboard into midi and then run it into a PC in real time?
There are, but they all suck.

I'd go and try MIDIguitar.
Name's Luca.

Quote by OliOsbourne
I don't know anything about this topic, but I just clicked on this thread because of your username :O
Quote by Cajundaddy
Clue: amplifiers amplify so don't turn it on if you need quiet.
Quote by chrismendiola
I guess spambots are now capable of reading minds.
I agree with Spambot. I have been heavily involved in midi for about 25 years and there have I seen several attempts over the years to create what you are looking for but I have never heard one that really worked. My suggestion is buy an inexpensive controller keyboard or a cheap used keyboard. There are tons out there for $50-100.00 that have midi built in.
Yes I am guitarded also, nice to meet you.
If you use Ableton, you can record audio then right click and convert to midi. It's like 85% accurate, and you just need to clean up a handful of ghost notes and stuff. It won't be in real time, though.
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