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View Full Version : phase shifting for inverted subwoofers??


ucme
25-09-2007, 11:39 PM
ok cant really find any info on this topic so heres my dilemma:

i have an inverted subwoofer which sounds like crap during some songs. the only reason for this i believe is that by inverting the speaker, the frequency needs to be inverted as well. i know some head units come with this inbuilt function and home theater sub's have this feature also. but what about the rest of us?

ive tried looking for some kind of phase shifting gadget to buy but to no avail. help needed:(
tron07
26-09-2007, 09:30 AM
Just swap the polarity for woofer speaker cable.
D4rk4n63l
26-09-2007, 09:40 AM
^x2, simple solution...
beeza
26-09-2007, 11:33 AM
Do you have a whole in the box for the air to move?
ucme
26-09-2007, 02:09 PM
Do you have a whole in the box for the air to move?

sure do.

what do u guys mean bout swapping from polarity to subwoofer cable?
aaronng
26-09-2007, 02:17 PM
Swap the signal and ground wiring on the subwoofer side.
ucme
26-09-2007, 08:44 PM
yep prob fixed. thanks guys
beeza
26-09-2007, 10:21 PM
Swap the signal and ground wiring on the subwoofer side.

Ah yes I remember now :o
You put the + to the - and vice versa on the sub :D
ACTI0NMAN-1
26-09-2007, 10:26 PM
you put the + and - on your tongue.
ucme
27-09-2007, 01:28 AM
you put the + and - on your tongue.

and then you become action man?
tron07
27-09-2007, 09:00 AM
and put a + rep for me :D
ucme
27-09-2007, 11:40 AM
:eek: cant do it yet for some reason
TRU32U
28-09-2007, 06:12 AM
lost kients dont swap polaritys on the speaker wires to the sub, u swap the polaritys on the rcas goin to the amp
if u swap poles it wont run efficiently, theory yes would work and same ending but reality its different...
add i cp rep to me...
D4rk4n63l
28-09-2007, 09:10 AM
lost kients dont swap polaritys on the speaker wires to the sub, u swap the polaritys on the rcas goin to the amp
if u swap poles it wont run efficiently, theory yes would work and same ending but reality its different...
add i cp rep to me...

swapping the RCA wont change a thing.... there is no relation of efficiency and polarity since speaker is simply a magnet and coil which moves up and down (or down and up, if you change the polarity) as you drive current to it.

Its all about SPL (sound pressure level), think about the car as a small volume box.. take the upper wall of the box as front speakers and the bottom wall as the sub. If you have the upper wall pushing down, you'd want the bottom wall to push up to increase pressure inside the box. If the bottom wall is 'out of phase' the volume of the box remains because the bottom wall also moves down and just cancels out the force from the upper wall... hope this helps u understand more
tron07
28-09-2007, 12:52 PM
Use a Phase shifter or Time Alignment also can
ucme
28-09-2007, 02:53 PM
changing the + onto -ve and vise versa did improve the sound of the subwoofer. as its inverted, inverting the sound improved the sound dramatically.

i don't think it made it louder, if anything maybe a little quieter, however i am more one for clarity and i don't think my sub is made to be inverted so this improvement was more than enough for me