I'm really not one to talk negatively about anything or anyone. So I hope this isn't perceived as such. This sub is of excellent build quality. However, i've heard this v2 in person and I think you would be paying me the $500 in this case.
Obviously, sound is very subjective. I was an audiophile for many years. It's what paid for college. To claim this is the best sounding sub or even a great sounding sub would be too strong of a comment imo. Yes, it can produce much much more volume than the stock sub but I would like to hear it with an eq/crossover that really tames the 120-160hz range which was much too pronounced with the sub. It's the typical problem when the enclosure is too small - the higher bass levels become very isolated and the speaker has problems pushing low notes in the 60-80hz range. At this point i'd much prefer the fullness of the OEM Bose sub even sacrificing some volume. This sub would probably be ok if someone listened to Kanye all day.
Not wanting to pick a fight or anything just want people to make sure to listen to the product first. I do hope their ears will like it. We need more support to vendors for our NSXs especially as the numbers decrease and the cars age.
Also, John is a stand up guy. This is probably the best sound you can get from such a small enclosure so kudos for that. I'm almost tempted to ask John to sell me an enclosure w/o a speaker cutout so I can try a 6" sub or perhaps a 8" sub. Maybe even experiment with some porting. I don't think I have a $500~ to toss around and just end up with a canibalized useless sub... ok.. i'm rambling.
