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Subject: Re: Slightly OT: Channel phase

Re: Slightly OT: Channel phase

From: Pedro Vasconcelos <>
Date: 2005-06-04

On Sat, 04 Jun 2005 10:48:44 +0200
Johan Vromans <> wrote:

> This leads to the following questions:
> 1. Is is true that phase matters?

yes, it afects stereo image and bass depth.

> 2. Is there a way to reverse the phase of one channel of an MP3 file
> so you can determine the correct phase by listening to the sound
> while playing the original and reversed versions?
> 3. Or maybe there's an easier way to find out the phase of a set of
> speakers?

Althought I cannot take resposability for the following procedure, I
have used it and think it should be safe: 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. I
think only relative phase between the two speakers matters, i.e. if you
reverse polarity in both speakers that shouldn't mater.

Again, I would stress that I won't be held responsable if you damage
your speakers trying this...

Received on Sat Jun 4 16:35:43 2005

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