I got the sub Diamond Audio 10" D6 500RMS/1000Max and custom box from a fellow Z owner. I then found a crazy deal on a Rockford Power series 600-2 amp from this site. I got it all hooked up and wow I have only had JL and Rockford subs before, but now Diamond Audio has my respect. It sounds so good. Its powerful deep and doesn't sound anything like a 10". I have some pics to show you guys the set up and some pics of the amp from rockfords site. I have the amp mounted in glove box. These are paired up to my Kenwood DNX7100.

 

while you have those panels off.. ditch them rear speakers

 

The Diamond D610 is a VERY nice sq sub. I had one before my current setup. It is a sweet sub that is in the same class as a JL 10w6......but better sound and build quality and less expensive (of course). You made a great choice with that sub. I'm glad you like the sound in the install you have.

 

So how did you seal the stock location against air leaks? What did the enclosed volume measure out to be - and how did you manage to measure it accurately?

You do understand that the woofer that you pulled out of a sealed box was put into a sealed box for a acoustical reason right? Subwoofers are designed to give amazing sound when working against the correct enclosure volume. The enclosure has to be perfectly sealed against any air leaks as it acts as spring to limit the excursion of the cone and functions as a part of the subwoofer to create tight and accurate base.

Thiel-Small for the win.

 

Looks like a decent setup. Any pics of it installed?

 

It looks like he took that carpeted enclosure and placed the entire unit inside the cubby behind the driver's seat.

See pic#5 & 6

 

The entire sub and enclosure fit in the stock location perfectly. The Z owner I bought the sub and box from had everything professionally built and tuned at an audio shop. He said it was built for clarity, but it also pounds! I couldn't tell you what the air space is but I trust him and the shop he bought it from. It wasn't a cheap build for just the box and sub. Altough he did give me a good deal
The bose cover actually snaps back on after everything is installed. He had the box mounted to the stock bracket but I put it in without the bracket to test fit and it is perfect. Just the right size.
The next thing I am doing is to dynamat or hushmat the area around the enclosure to keep all the sound going into the cabin.
For a convertible owner and even a coupe owner I think this is a great option to save space and get some great sound.