Side firing bass designs - Pros & Cons?...

Sean -

Thanks for posting the AR 9 owner's manual link! Great info in the room acoustics section. Methinks the folks at AR tore a page from the back of Roy Allison's notebook.

Another speaker that used a room-boundary-conscious woofer system design was the Snell Type A.

Back in '86 I built a pair of speakers using a 30" tall Gold Ribbon Concepts planar driver and a pair of 7" Focal woofers. To keep the front baffle area to a minimum, I mounted the drivers on the side. It was kinda cool looking - from the front, all you saw were the ribbons. The woofers were physically about 1/6 wavelength farther away than the ribbons at the 200 Hz crossover point, which was negligible. Both the woofers and the ribbon were loaded into transmission lines. If by any chance you have the 4/86 issue of SpeakerBuilder magazine, you can see a picture of it. In retrospect there were some radiation pattern discontinuities that I wouldn't tolerate today, but at the time I didn't know any better. Still, they didn't suck too bad.

Duke

I agree with the placement difficulties, I had a pair of Definitive Technology 2004Tls with the side firing subwoofer... it was hard to get the room to really fill.

I think they figure that since under 100hz is non-directional, they can place the woofer on the side and make the speaker slicker and sexier and easier to get by the WAF, which would give them an edge on sales...

I think a pair of monitors and a good subwoofer works better than towers with a side firing woofer. cause that is basically what you are getting, is a monitor on top of a subwoofer.

At least that has been my experience.

Just get Vandersteen model 5 or 5A's and forget about it!

Vedric

Duke: Roy Allison used to work for AR, hence the similarities in design. For that matter, so did Ken Kantor, who designed / helped design some of the NHT stuff. From what i understand, the woofers used in the 9's were made by the same company that makes the NHT 1259 woofer. Both drivers work best in big, low Q sealed boxes, which is what i like anyhow : )

Slappy: Bass doesn't become "non-directional" until pretty low. I think that even at 100 Hz, one can still pretty well "localize" the point of origin without much fuss if they know how to listen. This probably has a lot to do with the harmonics that the driver is radiating and the distortion too. Sean
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Sean is right, you need to get very low in crossover point before it becomes impossible to localize it. Even a nominal crossover point of 100 Hz will still produce audible sound at several hundred Hz due to the crossover slope, and this is very easy to localize. Most full-range systems with side-firing woofers are crossed over at or above 100Hz, in some cases well above.