Yes, it was likely just coincidence.
Your "listening experience" serves as anything but a valid comparison of preout voltages. There were literally thousands of variables...everything from your seating position in the vehicle, to the installation and setup of the systems, the equipment used in the systems, to the vehicle itself. Out of those thousands of variables, it's impossible to conclude that something as insignificant as preout voltage had a contributing hand in the differences you heard.
Especially since we can straight up tell you.....it's not one of the reasons //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif
I would personally go for that Alpine you mentioned, out of those two decks.
I think voltage was a fact that u felt it was more of a SQ system. There is a role with voltage, and it is that it gives cleaner sound. If there wasn't any difference, why would compagnies bother making high Pre-Amp Output voltage? And it isnt a marketing stuff, it really does sound cleaner.. I bet you if you go from a 2volt to an Eclipse's 8volt, you will hear manyyy difference... I suggest you get a decent head unit with Many Tuning options and featuress.. but STILL, get a minimum of 5v head unit IMO. trust me on that one
