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previous: Mike S cAN ANYONE EXPLAIN WHAT THIS IS AND... -- 1/14/2000 9:06 PM

Re: wHAT IS VOICE COIL RUB?

1/14/2000 9:19 PM
R.G.	Re: wHAT IS VOICE COIL RUB? The voice coil is suspended in the middle of the cylindrical gap between the magnet and the pole piece. Clean reproduction requires that it never touch either the pole piece on the inside of the gap or the magnet on the outside of the gap. If the voice coil, speaker cone suspension or spider get warped so that the voice coil touches the pole piece or magnet, it literally rubs against them as it moves in and out to make sounds. The rubbing is "amplified" like a string in an acoustic guitar and is very audible, a scratchy sandy sound or a 'ghost tone' kind of distorting quiet notes. To see if you have it, pull off the grill cloth or pull the speaker out and place it on a table, magnet down and cone up. Spread your fingertips into a circle and *GENTLY* push down on the cone, then let it up. If you hear a scratching or rubbing noise, you got it. If it's essentially silent, you don't.

1/14/2000 9:19 PM

R.G.

Re: wHAT IS VOICE COIL RUB?

The voice coil is suspended in the middle of the cylindrical gap between the magnet and the pole piece. Clean reproduction requires that it never touch either the pole piece on the inside of the gap or the magnet on the outside of the gap. If the voice coil, speaker cone suspension or spider get warped so that the voice coil touches the pole piece or magnet, it literally rubs against them as it moves in and out to make sounds. The rubbing is "amplified" like a string in an acoustic guitar and is very audible, a scratchy sandy sound or a 'ghost tone' kind of distorting quiet notes.

To see if you have it, pull off the grill cloth or pull the speaker out and place it on a table, magnet down and cone up. Spread your fingertips into a circle and ***GENTLY*** push down on the cone, then let it up. If you hear a scratching or rubbing noise, you got it. If it's essentially silent, you don't.

Replies:

Troy RG: It's weird but I hand tested th... -- 1/14/2000 10:02 PM