DCAudioDIY.com

The magazine is spacing out my articles over the next 5-6 months. My report on the Midwest Audiofest will be in the October issue. The article on my trip to Parts Express should appear in the November issue. My guess is the article on the Ultimax will appear in the December or January issue. Sometime after that will be the article on the VFET amp which believe it or not was the first one of the group I submitted. They always move the publication dates around to fit the mix they want in the magazine.

As far as the idea of putting the sub at the listening position and moving around the room to find the spot with the least offensive bass, I think that is a good idea as far as frequency response which is a major issue. Different positions will affect time delays in relation to the woofer but if you use DSP and a separate amp for the sub you can correct for that. Those time delays result in phase shifts in relation to the woofer and can result in cancellations which affect frequency response.

Generally the placement becomes more critical as the crossover frequency to the sub gets higher. If you could run the sub only below the the frequencies where the wavelengths were long in relation to room dimensions the placement would not be as critical. However, it would have to be a small room indeed if you plan to run the sub up to the 80 - 100 Hz range for that not to matter.

Tom