From: cullen@ac.dal.ca
Newsgroups: rec.audio.pro
Subject: Re: Monitor System Peaks
Date: 16 Dec 92 01:28:17 -0400
Organization: Dalhousie University, Halifax, Nova Scotia, Canada

Galen Watts writes:
>>BTW: anybody got a good way to figure out the peaks in a monitor system
>>(with out a spectrum anylizer:):)
>>Jack Van Breen (standard disclaimer, these are my own ...)
 
> Yes, we do it all the time with a readily available acoustic measuring system:
> Our Ears.
> You need to FLATTEN the eq, turn it up until it squeals at ONE frequency, then
> pull down the band on the eq.  The first time is trial and error, so maybe you
> shouldn't do it at a gig.  If the band you pull down doesn't affect the squeal,
> try the one above or the one below.

The cheater's way is to get it near the "regeneration point"* and start
slowly boosting each band untill it rings and then pulling it down, the 
earlier rings going down farther than the later ones. Note that this is a 
quick and very dirty way to do monitors, and either way, if you induce really
high levels, you run the risk of damage before the band even gets onstage.
Most Embarrasing ;8-() (* for fans of Davis and Davis 8-)

> Until you get to the point where you can tell what band by the sound, it's 
> going to be hunt and dip, but once you know where your monitors have peaks,
> you know which ones to dip first.

Commonly referred to as pitch or ear training in music circles. I actually 
had a sax player tell me that the monitors were ringing just a bit at
B below middle C, and boy, was he surprised that I got rid of it instantly.
Also, as an aside, musicians never believe me when I tell them that
really good engineers have really good pitch, but you gotta, not in terms
of note but in frequency, and you have to get the harmonics, as well as 
the fundamental.
 
> One thing that really bugs me is monitor engineers who use the 31 band eq's
> for tone shaping, like when they grab 500-2400 Hz and pull it all down so the
> "curve" on the sliders looks good.  31 band eq's were meant to NOTCH out peaks,
> not as a Bass-Mid-Treble device.  
> You cannot boost and you cannot cut more than 6dB without changing the response
> of the EQ outside of the band your adjusting.

Well, sometimes you do what you have to do. If you have a howl at 6.3kHz, 
from really bad reflections, and a mic with _PRESENCE PEAK_(ARRGH), sometimes
you have to do the big scoop to save the gig, obviously at the expense of the
monitors. 

I think that the "Nice Curve" approach that I often see is people who have l
earned/been taught to mix on a system that has constant directivity horns, 
and no eq in the crossover, so that you have to do it on the graph. They 
have learned that the eq _should_ look like that, and then come onto a 
system with horn eq, or no constant directivity, and do the same thing, 
and get a really forward presence (read unbelievably fucking bright), and 
think that thats a great sound. Then they come to our bar, with the Bose 
802 system (BOSESHIT (TM)), no horns, just 64 four-and-one-quarter inch 
drivers, and just loose it. HAHAHA! Then, halfway through soundcheck, they 
ask how the curve _should_ look. So I flatten the curve, and fix 125, 200, 
400, 630, 800, and 1k, (Bose problem points), and say "that should be fine".
And it is! HAHAHA! 

But, seriously, I have seen a disturbing trend of dual operators locally, 
the band soundman, who mixes, and the PA tech, who fixes the graph over 
his shoulder. Even in Arena gigs. This is crazy! Why does anyone 
bother to pay a soundman for a tour if he has to be Babysat?
						Mur
						Cullen@ac.dal.ca
						Cullen@ug.cs.dal.ca
I will be off-line from Dec 19 to Dec 27.
Newsgroups: rec.audio.pro