which is best, sub driver up facing or down at floor

[Bill poster]

Stupid question maybe
i'm making a slim sub (with TB w6-1139) enclosure to go under a sofa- the floor clearance of the enclosure is about 5-6 cm with the feet, so i'm wondering what most people wd recommend, up facing driver or down?

 

[DUG]

up: vibrate sofa or just get absorbed by sofa? box can sit on floor
down: down into carpet or hardwood or ? box has to be spaced above floor
down angle: aim subs towards front (or rear) gap of sofa

Things to think about.

 

[Bill poster]

as I need a 5-6cm space under the sub as the plate amp is also mounted underneath .. maybe it makes more sense downfiring- otherwise i need a certain gap above which cant be guaranteed

 

[Zero D]

Something to consider is Gloss

Gloss tells how many percent of Xmax driver cone will sag, if driver is mounted horizontally. This figure is only approximate, because surrounding air shifts resonance frequency to somewhat lower value. So result is somewhat over-pessimistic by some amount. Generally, figures of more than five percent tell you that driver in question shouldn't be mounted horizontally. Value of gravity acceleration used when calculating sag is 9.80665 m/s².

From WinISD Pro Help File

 

[nigelwright7557]

Something to consider is Gloss



From WinISD Pro Help File

This suggests the driver will not move up as much as it moves down due to gravity and so will distort the sound.

 

[adason]

Stupid question maybe
i'm making a slim sub (with TB w6-1139) enclosure to go under a sofa- the floor clearance of the enclosure is about 5-6 cm with the feet, so i'm wondering what most people wd recommend, up facing driver or down?

neither is optimal
woofer facing down will sag out, you got lower efficiency as voice coil will be moving out of gap
with woofer facing up, you get sag inside, which may result in earlier bottoming out
sounds like your space will result in lots of resonances
better do a proper job and make conventional sub

 

[Kingnoob]

front firing is the best sub-woofer design IMO

 

[jcx]

up!

Cornstarch, Water and Subwoofer - YouTube

 

[deebeez92]

http://www.diyaudio.com/forums/subw...river-orientation-effects-t-s-parameters.html

This thread will answer your question. Each orientation is slightly different, and the variations have been graphed.