They don't get enough love/attention IMO. I know there's been a conflicts between Tom and the Audioholics crew but that shouldn't get in the way of the OBJECTIVE truth.
I'm personally considering a pair PSA S21 Ipal or maybe even a pair of S42 Ipal's as my end game. Living in Canada I can't really afford to be "trying out/Demo'ing" different subs. Also the S21/S42 dimensions have significantly higher WAF for a living room setup. I'd consider JTR if they made a dual opposed subwoofer.
Just take a look at the DIY Dual opposing B&C 21-Ipal with a smaller enclosure VS the PSA offering. It bested the FV18, FV25hp, JTR S2 and only 1dB from the vented Cap 2400's. I don't know why anyone would claim PSA subs can't do ULF unless there's personal vendetta going on here. I'm sure the S42 Ipal is very comparable to the JTR RS2 that gets constant praise, assuming the newer JTR drivers gains 3db that would put it on par with the 21 Ipal below 20hz, and who know's what output PSA gains with the larger cabinet vs this DIY kit.
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