I went with the 20-39 PCi for a couple of reasons:
1.
Needed an SVS that could hold its own whether it was music or movies in a medium sized room (30 x 14 x 8).
The 20-39 does exactly this for minimal punch to the wallet. SVS themselves describe the 20-39 as a "best of both worlds" solution and I would have to agree. I was willing to give a little on the musical end to get the low-end extension with a 12", fortunately I don't feel the 20-39 sacrifices much if anything.
2.
Wanted solid performance (not the low-end, but certainly not the high-end) at a step above the entry level SVS offerings.
While SVS subs are superb values, they're still not pocket change to the average Tom, D!ck and Harry. The 20-39 is a step above the PB10–ISD and is equal to the PB12–ISD, but after calculating shipping costs for the two, the cylinder saved me more than $50.00 and considering in my application it's hidden, the WAF wasn't an issue. Even if it was, I find the cylinder more appealing than the standard box sub.
Unless you have a 'hang-up' about cylinder shaped subs and they need to be in a box or if the box shape better suits your application or listening environment, the cylinders are a better value.
If I were to do it over again, I would purchase a 22Hz tuned version of the 25-31PCi for just under $575. This would give me (almost) identical performance of the 20-39 in a smaller footprint. Would also save me another $50.00, tough price/performance value to beat by any other manufacturer. Because of my constant battle with upgraditis, I may some day move to a Plus version, but by no means does that mean I'm I not satisfied with the 20-39 PCi. It's just further proof that upgraditis is a real sickness...
-TD
