I tested the JBL 2204 free air and got results similar to the specs, Fs was 39Hz. I put the speaker in a 1 cu ft box and the Fs dropped to 14Hz???? According to UniBox I should of had a Fb around 75Hz or so.

I tested it several times, same results. The only difference is the box and 4 ft of speaker wire.

I have tested subs free air, sealed box, and ported and got results that were predicted. So I 'think' my test method is ok.

Help