Question about EQ and Phase

[homerecor]

My friend explained to me that analog equalizers work by manipulating the phase of each frequency. For example, to lower 1000Hz, the filtered signal is split into two parts, phase reversed on one side, and then blended back together by a certain percentage to cause cancellation. He says this can cause phase issues with the overall mix.

He then went on to say that digital equalizers don't use the phase technique. They can simply boost or attenuate any frequency point mathematically.

So what is wrong with putting a digital EQ in my signal path to help tune my nearfields?

 

[Rodger Hartlett]

and what sort of digital equalizer would that be? a passive shelf equalizer should not have phase issues. your nearfields would be pretuned anyway . what don't you work on the room or change the poweramp.

 

[homerecor]

Yes, my monitors are okay. It is my room that sucks pond scum. I rent here so, I cannot go nailing or gluing panels to the walls. However, I am buying a new home this Summer/Fall and believe me; I will tune whatever new room I end up with.

I have a new Behringer DEQ2496. I heard they are fairly clean. (Well, as budget gear goes, anyway.) I got it for the RTA feature, but why couldn't I just leave it in the signal chain using a resulting curve from the analyzer?

 

[boingoman]

He then went on to say that digital equalizers don't use the phase technique. They can simply boost or attenuate any frequency point mathematically.?

Your friend is mistaken on a couple of things.

First, though the methods may be different, digital EQs introduce phase shift as well. A poor digital design will have worse phase characteristics than a good analog one. And at the top of the heap, the differences are pretty miniscule.

A poor or even good eq design, analog or digital, can exhibit phase shift (sometimes lots) even with all controls flat.

Second, if your eq is in your monitoring chain only, any phase anomalies will be in your monitoring only, not put into your mix.

So what is wrong with putting a digital EQ in my signal path to help tune my nearfields?

The same thing as putting any eq in there. When you start tuning your system to fit the room, you get another step farther from what your mix actually sounds like.

Also, an eq cannot compensate for some room anomalies, such as cancellation. If 250hz cancels in your room at the listening position, no amount of eq will bring it back, and you won't ever hear what is going on there. This could lead you to bad mix decisions, and if you saw this on an RTA, it could lead you to the conclusion that your monitors have a dip at 250, which would be incorrect.

 

[TexRoadkill]

Gotta agree with Boingo. Phase distortion isn't the issue here. It's the fact that EQing monitors only gives you a small sweet spot and won't truly balance the sound in the room.

You can still put up treatment without attaching to the walls. It's actually better to have it off the wall a few inches. Just build some stands to hold up the panels.

 

[distortedrumble]

Gotta agree with Boingo. Phase distortion isn't the issue here. It's the fact that EQing monitors only gives you a small sweet spot and won't truly balance the sound in the room.

You can still put up treatment without attaching to the walls. It's actually better to have it off the wall a few inches. Just build some stands to hold up the panels.

lets also not forget that your "tuning" will sound the best on your system....sometimes having a somewhat dry all around sound is good because most people have the treble and bass jacked up on their systems. if you have the treble and bass already pumped, they cant turn it up as loud as they would a professional cd.

thats a quick pass through but there are so many arguements weaved in and out of there.