Hello friends
The SB12 Plus was just gorgeous to look at and so ... easy to handle.
I purchased the sub to set up my second listening room in the garage for 100% music. To my ears, the SB12 didn't have the lower reach that I was hoping for, that I have gotten used to listening with the MFW 15. Maybe it's the smaller size.
I then switched it with the MFW-15 in the primary room to watch a movie. My wife and I both agreed that the MFW 15 was a better sub for our purposes.
I emailed SVS the next morning to request a return authorization and got a prompt reply. But the actual shipping back took 2+ more weeks because the UPS label was never sent. It took 2 or 3 more emails but, nevertheless, I thought that SVS has great customer service and am considering purchasing the PB13 Ultra in the near future from SVS.
I thought you might find the SB12-Plus a bit lacking in output and extension after using the MFW-15. A tiny sealed enclosure with a 12" driver simply can't keep up with a larger ported enclosure with a 15" driver, especially down deep. The two subs are clearly designed with very different goals in mind. The MFW-15 looks great but is larger and has a larger appeal to HT users. The SB12-Plus is targeted toward the decor-conscious user who requires good bass in a very small package. I've read of users who have used dual SB12-Pluses as stereo subs for music systems with great success. I also think the SB12-Plus would be impressive to many people as a HT subwoofer in small to medium sized rooms. Since you already own an excellent subwoofer in the MFW-15, your bass standards are already much higher than most

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BTW, the Ultra is an excellent subwoofer and should be a noticeable improvement from the MFW-15. If you put the Ultra in its 15hz tune, you'll really notice the extra depth and power down low over the MFW-15 with certain movie soundtracks.
Thanks for posting your impressions. I always enjoy feedback from people who have used several different subwoofers. While I'd love to audition many subs myself, subjective reviews by people who have heard several themselves (particularly in the same listening environment) are the next best thing. Keep us updated if there are any new developments

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