dev builds
themes manual
device status forums
mailing lists
IRC bugs
dev guide

Rockbox mail archive

Subject: Re: Slightly OT: Channel phase

Re: Slightly OT: Channel phase

From: BlueChip <>
Date: Sat, 04 Jun 2005 17:44:08 +0100

>>>Take a 1.5 AA cell and two connecting leads; connect the + and - of the
>>>cell to the loudspeaker terminals; you'll hear a small "pop" and the
>>>bass driver will move slightly, either forward or backward. The drivers
>>>of both speakers should move in the same direction when the polarities
>>>are matched.
>This is the procedure I've use many times, to check speakers. I usually
>find a 9V battery works better though.

9V !!!???

Quick check:

9Volts into 4Ohms -> 2.2Amps
2.2Amps _at_ 9Volts -> 20Watts

That'll be "20Watts RMS" or "26Watts peak-to-peak" or "about 1'300Watts PMPO"

So 9V would kill most desk-top speakers, but work well with stage kit.

>>>Ithink only relative phase between the two speakers matters, i.e. if you
>>>reverse polarity in both speakers that shouldn't mater.

Depends on your speakers.

If you just have a cheap cone with two wires - meh.
If you have isodynamic speakers or a cross over or one of many other things
- it WILL matter.
I know hifi purists who are convinced they spent good money on SPEAKER
CABLE that has a right and a wrong way around.


Received on 2005-06-04

Page template was last modified "Tue Sep 7 00:00:02 2021" The Rockbox Crew -- Privacy Policy