Circuit for variable phase 0-180 control for active L/R xover

[georgehifi]

Ive searched but no joy.
Variable 0-180 phase control circuit to adapt to my 24db L/R 2 way active xover?

Thanks George

[richie00boy]

Look on the ESP site, but take note of the warning in the article regarding how they destroy phase consistency across the band.

I just use an inverting op-amp and a switch to choose normal or inverted, no phase abberations that way.

[georgehifi]

Originally posted by richie00boy
Look on the ESP site, but take note of the warning in the article regarding how they destroy phase consistency across the band.

I just use an inverting op-amp and a switch to choose normal or inverted, no phase abberations that way.

Found it http://sound.westhost.com/project103.htm
yeah maybe a waste of time, I measured with a db meter at the xover frequency 160hz and got a difference of -6db when reversed, naturaly I went with the louder one and it sounds much better. Is a difference of 6db usually the case if things are 180 degrees out? Meter measured 78db then 72db in a quite room (40db) at the xover of 160hz 3 meters from the speaker.

Thanks George

[richie00boy]

The amount of dB difference would vary with position, I would imagine. The main thing is that you just choose the setting that sounds best to you. For me this is usually the louder one as it seems to give better integration.

[lumanauw]

Hi, Georgehifi,

It should be something like this. In opamp handbook it is called "all pass filter". Unfortunately it's correct value of phase shift is only on 1 frequency, not a frequency band.