Byrdman,
I actually had an ETEC on the boat before the EFI Honda. The Honda is much quieter than the ETEC door open or closed. With the door closed on the Honda, the loudest noticeable sound is the water going by the hull. The ETEC had a couple of throttle settings where a resonance set up that forced you to change the throttle up or down a little. The Honda shows pretty much a linear noise profile.
I actually had an ETEC on the boat before the EFI Honda. The Honda is much quieter than the ETEC door open or closed. With the door closed on the Honda, the loudest noticeable sound is the water going by the hull. The ETEC had a couple of throttle settings where a resonance set up that forced you to change the throttle up or down a little. The Honda shows pretty much a linear noise profile.