Phase Question

[Ruphus]

Ladies and Gentlemen,

Can someone help me understand what´s up in the following case, please?

I´m having three tracks of a lead vocal which I want to merge. It´s the same thing just one time clean, one time slightly compressed and another time double compressed.

I lined them up by the waveform zoomed in, but found that they would cause a phase chaos that way which made the vocal spreading all over the sound field.

Next I shifted them a bit around in milli-measures to see how they would maintain their content best ( which seemed to be both compressed takes aligned while the clean track staying slightly ahead ).

To get it more focussed in the stereo field I then compensated with panning which resulted in a workable situation ( the mix isn´t too crowded and allows the vocal to be somewhat broader ), but I´m sure that there must be a more intelligent approach that I could try next time when having a similar case.

How should one approach to such? ( Apart of the option of partitioning and recombining them in individual frequency ranges.)

Thanx!

Ruphus

[StefanM]

Did you use a plug-in or _digital_ outboard compressor on the tracks? If so this would introduce latency that has to be corrected.
(The better DAWs like PT HD or NUENDO can do automatic latency corrections) but of course this can be done manually too.

Stefan

[Ruphus]

Hi Stefan,

Thanks for the suggestion, but if you read my post again you will see that it is not about latency.
The compressor used has been outboard, but I was shifting around anyway.

Thanks again,

Ruphus

[Ethan Winer]

Ruphus,

> It´s the same thing just one time clean, one time slightly compressed and another time double compressed. <

Do you mean you have a single performance that was processed three ways, and you're aiming to combine them to a single track? If so, I advise against that because it creates exactly the problem you described. Much better is to compress it once to have the amount of effect you want, and be done with it.

The same goes for EQ'ing the same performance multiple ways and combining. All you get is wierd peaks and nulls. This is what you perceive as a "phase" problem even though it's really just a screwed up frequency response.

--Ethan

[tINY]

What you hear is the freqency weirdnes, but it is caused by phase issues.

The problem is that phase is not constant. The outboard compressors introduce phase lag that depends on frequency and compression.

You can never get all three signals lined up again. You would need to phase compensate based on frequency and the compression level of each track at each point in time (the frequency dependancy probably changes with compression too)



-tINY

[StefanM]

Agreed: Even analogue outboard compression may introduce phase problems - but anyway parallel compression does work, or not???

Stefan

[Ruphus]

Hey guys,

Thanks a lot!
Thought I might be doing something wrong, but was just ... doing something wrong.

Great to get some feedback and learn that I shalln´t do that again.

It´s a bright female voice over a dark background ( lower department dist guitars, bass ´n drums ). Intended to thicken up the mids of the vocal without emphasizing its highs, because them being too essy. ( Carved out with FFT already, but had to leave some ess range in to keep the core.)

You are right, no matter how I shifted the tracks today the phasy phenomenon accompanied by some tuby sound remained. So, finally I decided to leave them out.

A simple EQ shall help.

Muchas gracias.

Ruphus