Re: Infinity Basslink?
The Basslink is nice, but there have been reports of them failing right out of the box. I've heard the Basslink in a customer's car and it was quite boomy sounding, but it had decent output. I've not heard the Basslink II. The Pioneer option you mentioned is also decent, but I think the Basslink would get louder. The passive radiator makes it more efficient than a single sealed shallow sub.
If you're really tight on space I'd get a small amp and either a loaded Alpine 8" box or a loaded JL Audio 8" box.
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