You are listening to an arrangement of the famous Hornpipe, transposed down a sixth to F major. This version includes some improvisations (with one variant in d minor).
The long 9+ second full release tails of the Esztergom Bascilica caused me to perform the work slightly slower than usual, with detached notes, and with some unusual grand pauses, so as to render the sound intelligible.
EDIT: The uploaded audio file is a 320kbps MP3 file -- two previous upload attempts would not accept the 89MB .wav file. As such, one hears MP3 artifacts (crackling noises) in the left channel towards the end of the piece, that do not exist in the original file.
The sound you hear contains absolutely no post processing in the form of equalization or third party reverb units. I did put a brick wall limiter while making the original recording, because the dynamic range of the organ is so great. It is almost too much for the 16-bit 44,100Hz sampling rate normal to CD quality.