Joe Blow's guide to subwoofer setup

[Jethro The Switzerland of Audio Find all posts View Profile Close Jethro]

Does this exist? I think I have my subs set up pretty good, but is there a simple guide for setting the polarity? I snooped around at audioholics but not much jumped off the page at me. The phase is where I'm pretty much at a loss.

Here's how they are setup...



They are in the same locations for the most part... just tweaked a bit.
I know I can move them around the room for better bass, but what about the phase? I have them both set at 0.

TIA... Jethro

[bunnyma357 Find all posts View Profile Close bunnyma357]

I haven't used this, so I don't know if it will help.

http://av123forum.com/showthread.php?t=3418

Jim C

[Jethro The Switzerland of Audio Find all posts View Profile Close Jethro]

I haven't used this, so I don't know if it will help.

http://av123forum.com/showthread.php?t=3418

Jim C

Seemingly thorough write-up here. I'm looking for a quickie on setting phase for dual subs.
Thanks for the link however :thumbsup:

I'm sure I'll read it over tonight when I have some free time to make sure I didn't leave anything out.

[dane The smilies here are SO pretty Find all posts View Profile Close dane]

If you want a "quick setup guide" for subwoofer integration (single or multiple):

1) plug in
2) turn on

If you want to truly integrate it into your system, there are any number of things to look at ... placement, "generic phase", EQ, room treatments, etc..

If you are happy with placement and just want to do generic phase setup, then play a tone at your XO frequency and using an SPL meter at the seating location, adjust the phase of the sub(s) until the output SPL at the XO frequency is greatest. HOWEVER-- this method does next to nothing for true subwoofer integration. The most basic next question is, "What does it look like over the entire XO range?" (XOfreq +/- 20-50Hz)

Room EQ Wizard (and other softwares) help give you the proper information to do better integration.. Sometimes just physically turning the sub (if your placement options are limited) can have profound (or negligable!) improvements.. But you won't know any of that if you don't graph your frequency response.. Subs individually, combined, with and without your mains playing, ...

But, like I said, if you want just a very basic, "generic phase" adjustment, then just use the simple instructions above.. bossobass's guide is a VERY good one.. Might take some time to swallow all of it, but when it comes to subwoofer integration, "investment in = investment out."

good luck.
..dane

[craigsub Find all posts View Profile Close craigsub]

Jethro - Here is a pretty easy, quick way to do this. You need a Radio Shack or other SPL meter.

1. Set meter to "C" weighting and Slow

2. Unplug or turn off one of the 2 subwoofers.

3. Calibrate your system so that a single subwoofer is in proper phase with your main system. Set the subwoofer so that it is 3 dB below reference. Set properly, the second sub will add 3 dB (this will vary thanks to the room, but it's what we have to work with).

You do this by running an 80 Hz sine wave through your mains, then through the sub, adjusting the sub until it is 3 dB below the reference of the mains. Next, adjust the phase until the subwoofer it at its loudest point, and leave the phase there. Readjust the sub volume (if needed) to 3 dB below reference.

4. Set the other subwoofer at the same gain level as the first, and run the same 80 Hz signal. Turn the phase knob on the second sub slowly until you get the maximum volume of the 2 subs together.

Your whole system should now have proper phasing, and then you can decide if you want to increase the subs for a little "hotter" bass.

[dane The smilies here are SO pretty Find all posts View Profile Close dane]

You do this by running an 80 Hz sine wave through your mains,

...if your XO is set to 80Hz...

:huge:

..dane

[Jethro The Switzerland of Audio Find all posts View Profile Close Jethro]

Thanks Craig and Dane. Just what the Dr. ordered :)

[Sean_W_Smith Find all posts View Profile Close Sean_W_Smith]

Also if you have an audessy equipped receiver then audessy will adjust the distance which is almost the same as phase automatically. evidence from a large sampling of users points to the fact that its very good at getting this right. At my house Seaton setup was 22.0 feet and audessy said 21.5 feet.

Sean