AV Rant Listener Andy —

had some corrections and clarifications regarding the floor bounce. He wrote:

“Floor bounce can be avoided “in the crossover” with a three way tower that has a woofer at the bottom of the tower’s baffle. The idea is to crossover high to the woofer so it is putting out the majority of sound in the 400Hz and below range, so crossing around 800Hz with a 12db slope would do the trick. Alison speakers were known for being one of the first to do this. It does not really remove the effect, it just gets it out of the midrange, although ceiling bounce, which is not predictable, may put the effect back in there. Don Keele’s CBT array is the only way I know of to avoid floor bounce 100%.”

Andy also linked to an interesting “Floor Bounce Calculator” with some very good explanation: http://tripp.com.au/avfcbm.htm

AV Rant Listener Mark H. —

wanted some clearer definitions of room sizes. What exactly constitutes a “small”, “medium”, and “large” sized room?

Audioholics created an extensive room size guide for subwoofers:

http://www.audioholics.com/loudspeaker-design/subwoofer-room-size

And THX has their own guidelines to go along with their THX Select and THX Ultra certifications:

http://www.thx.com/consumer/home-entertainment/home-theater/thx-certification-performance-categories/

AV Rant Listener David V. —

joked that his father wound up building a room within a room “without knowing it” just to avoid noise from his neighbors!

We’ve no idea what sort of plans were used, but if you’re planning on building a room within a room on purpose, a good thing to know about is the “triple leaf effect”, which is expertly explained by the good folks over at Sound Proofing Company Inc:

http://www.soundproofingcompany.com/soundproofing101/triple-leaf-effect/

AV Rant Listener Jay —

wanted to know which front projectors Tom and Rob would purchase for themselves given a few parameters. Tom would most likely go with the JVC DLA-X35, while Rob would pick the Sony VPL-HW55ES.

The question got Rob H. thinking about 3D, though, and the mentioned the Omega 3D dual projector lens system on the podcast. Obviously, using two projectors means increased cost. The objective is to be able to use passive glasses, rather than the active shutter 3D glasses that are necessary with a single projector system.

Most passive 3D systems use polarization, and polarization requires a special silver screen. The Omega 3D system is different. It uses special, narrow color filters so that you can have passive 3D while using just a regular white projection screen. It’s pretty interesting, so check it out!

http://www.omegafilters.com/Capabilities/3D_Glasses_and_Projection_Filters

AV Rant Listener Michael —

wants to start a small DJ’ing service. We recommended checking out Yamaha’s StagePas systems:

http://www.yamahaproaudio.com/global/en/products/pasystems/stagepas_400i600i/

and Behringer’s PA speakers:

http://www.behringer.com/EN/Category/Loudspeaker-Systems.aspx?s=K300

But Tom was trying to remember the speakers that Clint had used for an outdoor party. Tom was thinking the wrong brand. Turns out Clint’s speakers were the M-Audio M3-8:

http://www.m-audio.ca/products/en_us/M38New.html

Rob H. made some potentially debate-worthy comments regarding the usage of “Direct” and “Pure Direct” listening modes. He’s also strongly in the camp that if you have subwoofers in your system, you ought to use them at all times – for both music and movies, whether it’s 2-channel or surround sound.

But what do you think?

We’d love to hear your feedback on this topic. So sound off in the comments below!