So it's not about just tacking onto small monitors extra bandwidth. Any box boomer can do that. It's about minimizing room blur, front-corner pressure zones and box talk to improve bass timing, control and speed. Slow bass is real. It's no myth but a miss once we hear perfectly damped directional bass. That despite an expired patent standalone Ripol subs remain virtual unicorns and even rare built into speakers doesn't invalidate their effectiveness. If you find standard box bass problematic, spotting an add-on Ripol sub is a rare sight. Nearing on a parallel track of rarity is Pál Nagy's Gradient Box. That smart fully remote-controlled crossover will give advanced subwoofer integrators an unusually flexible tool to hone their craft. I'll combine both. On another parallel track move Stereophile bunker man Herb Reichert's expanding subwoofer tales. If you're still on hold with the sub-for-music topic, his reviews on the SVS 3000 Micro and KEF KC62 make good reading. If you do German, add multiple Velodyne installs by different members of the HifiStatement crew. John Darko in Berlin has made a KEF micro sub a permanent addition to his setup and plans on a second. On this subject long overdue, attitudes are changing. Perhaps it's time you got in on the action?

As this photo showed, a subwoofer can also shrink your boxes. This often looks better, sets up easier and, all else being equal, comes in for less. When monkey coffins are out and refrigerators exclusive to the kitchen, the job description of monitors + sub reaps dividends on multiple counts. Best off are those who plan this division of labor from the onset. It avoids discarding paid-for bass extension in big tower speakers. It can save big by sidestepping overkill constructions where loud woofers share a box with a midrange/tweeter. It can save on speaker amplification no longer being tasked with low bass sucking up most the power. To maximize these gains just wants a solid plan so you don't waste money and time remodeling a system which could have been built this way from the start. If you come from a big complex tower rig wishing to downsize without giving up bandwidth, the sub/sat music system too becomes very sensible. This from someone who did it the other way for nearly 20 years. Call it hard-earned smarts which you could exercise a lot sooner. We all learn from or own experience. Some people also learn from other people's mistakes. Just sayin'

August 23rd. "I'm hoping you're both settling into your new digs and that the move went okay. Apologies for the silence. Earlier this year we found that our old chalet needed a new roof. One thing led to another and we're presently in total kaos. We ended up gutting the place and hope that by November we'll have a shiny new home plus new workshop and listening room. Went all the way with 100m² photovoltaics, heat pump and under-floor heating plus a serious amount of insulation. Most the ripout is done and we're starting to put it all back together again. Working out of my old office—the only room still habitable—and an apartment in the village.

"The DSUB 15 is nearly there, just want to try some filter foam on the rear to see if I can get a bit more loading. Since I had to break it down for the move about a month ago, I've been having real withdrawal symptoms. Had only set it up with my MiniDSP/250-watt ICE amp and the Liber|8 about 80cm forward of the main speakers. It really does work a treat. The main takeaway is the subtleness and speed of the low end. It's not really there but when you turn it down, you know what you're missing. I'm going to try and ship it out to you in a few weeks. It's 60kg so may have to go road freight."

I'd use my Pál Nagy icOn 4Pro SE preamp with integral hi/lo-pass filter plus had external 4th-order filters at 40Hz, 60Hz and 80Hz so didn't need to wait on Martin's own. As driver I had the 250wpc Kinki Studio integrated with precision volume control. The unusual Swiss sub wouldn't be the beast from the East but perhaps the best from the West? I couldn't wait to hear it in our new 6x8m sound room which was just a bit shy on low-end power. If you wondered why I mentioned Martin's chalet remodel, it was to show that he doesn't do things half-assed. Once committed, he goes all the way even if it exceeds original plans. He's more of a double-cheek guy. That applies also to our review subject: two woofers not one, each 15" across not 10" or 12", rigid box, exotic loading, external electronics. Yet despite all seriousness of purpose, it still presents as reasonably compact. Or so I thought before it touched down and my furniture dolly cranked back.

Downstairs prepped for arrival. I hoped that on its high shelf, the preamp's display would just peek out above the sub to let me see the volume figures and access the IR eye. If not, the sub would sit slightly off center.

That'd be mid November. "Apologies for the long silence again. Lately this house renovation has taken wind out of my sails. Swiss builders don’t seem to be any more on schedule than elsewhere. Doesn't help when the plumber's five employees must get quarantined for two weeks because of Covid. Anyway, we're slowly getting back on track and should be able to move in again next week. I'll have a dedicated listening room and new larger work space and no longer will have to schlep all those speaker up two flights of stairs. You'll be pleased to hear that the DUSB15 is packed up ready to be collected tomorrow for its trip to Co. Clare. I've not been able to give it a full workout so you need to run it in a little. There's a 3m Vovox cable included and a set of basic feet. You may want to try some other options. I put filter foam at the rear which helps loading a little. If it sounds too muffled just remove it. Two small wooden strips bond to the foam on either side. These will pull out of the grooves easily."