I shared this in the Ted Appreciation group on Facebook, but I'm pleased to say that I've found a method for reducing the background noise from the "Live at the Seashell" videos on YouTube. There's a playlist of the remastered versions here:
https://www.youtube.com/playlist?list=PLHyebay_8doeQno0fMFIoM1Zs-YJRuT41 (contains all 9 videos)
A few points - this isn't just noise reduction or EQ. Instead it uses some new AI technology to separate the guitar from the conversation "intelligently" and I think the results are pretty good. The tone of the guitar is still there and clearer in some cases.
I did play around with other remastering techniques and EQ but it didn't make a huge difference - I'm happy to provide the extracted audio files to anyone if they wanted to have a try themselves.
Also, this is only based on the videos that I pulled from YouTube - they're over 10 years old so the resolution is quite low. If anyone here could provide me with a higher quality transfer of the original footage I'm confident that we could produce something even better.
Finally, I'd love to know if any more footage exists - even if the audio was previously considered unusable, this new process has been quite impressive and might yield better results.
I hope everyone enjoys these - I'm glad to be able to give something back to this community and honour Ted in whatever way I can.