These are the transition pieces I built for a better fit of the D54 to the square horn mouth pf my midrange horns.
The the measured difference is negligible. I expected someting more. Right now I have them installed for a couple of weeks.
Not much of a difference to me now.
Let’s see if I will notice a difference when I remove them again.
Update: Jan. 7th. ’03
Just before Christmas, I removed the adaptors again. Very interesting effect: Brighter and more open sound. Better sounding than before. Inceredible, but I did not hear that much of a difference when I put them in.
Conclusion: Some more wood for the fireplace this winter 😉