David Gilmour’s seagull effect on the Pink Floyd track Echoes: Plug your Wah in backwards, set to heel position and roll tone knobs back on a Strat! The guitar signal won’t work but you’ll get musical oscillation. Then add some echo like this TEFI Vintage Lab Ms. Delayette! Many pedal companies have releases a standalone version of this reversed wah in compact form. Check out the Jam Seagull here!
https://tinyurl.com/JamSeagull
Guitar: Redtail Guitar '62 (Fralin Vintage Hot Pickups)
Pedals: TEFI Vintage Lab Ms. Delayette https://www.youtube.com/watch?v=Z8GN5dWBpIU
Amp: D Kowalski Dark Gene Amp https://www.youtube.com/watch?v=sMeJhvZsTOU
Two Notes Torpedo Captor X https://www.youtube.com/watch?v=cP7_4RRQvJs