I've decided to go for an IB but I'm trying to do it on a smaller budget than is ideal. So if anyone has 4 AE IB15s, 4 FI IB15s or 2 FI IB18s for sale let me know. I'd prefer the 2 ohm FIs 18s and 4 ohm FI IB15s but would consider any variety ;D
Thanks - I had no idea they didn't meet the T/S parameters. They sounded great in my system. I mentioned directly in my post that they are a few years old.
"I have 4 AE IB15s for sale they are the 4 ohm version. They are a few years old but are in perfect condition. They were used in my home theater for about a year then I moved to Florida and have no room for an IB."
I used a set of 4 of the 32Hz AE IB15 poly cone drivers in my vertical array and then later in the manifold. Eventually they worked fine with a load of BFD boost at 20hz @ 2 octaves filter width. I used +16dB! Sensitivity was lower than the later paper cone drivers and they died too early (in Hz) without serious boost. I have a feeling that they'd work fine for some serious upper bass boost in my system to augment the present IB.
Here's the difference between the poly cone and paper cone frequency responses in my room without EQ.