Question for live sound folks

[jamsmith]

What are your experiences using autocorrecting EQ for mains? Please indicate what size audiences/rooms you are working?

[tINY]

The only auto EQ I ever used was the feedback eliminator types.

These work suprisingly well.




-tINY

[JimmyM]

I can't say I have used them personally, but I do plenty of gigs where they use them, and from what I can see, they're great. Never heard a soundman say a bad thing about them.

[johndykstra]

I've used DBX's Driverack PA extensively and absolutely love it!!! It's great as a starting point, but I still want a tactile graphic in the chain for quick moves. I mix every weekend in a club that has one installed, cap. is 250 or so. Using one on a mobile would work, but being that the auto eq functions through pink noise, you have to be allowed to make some noise. Cafes and such can be problematic. However, even if you don't use the "auto eq", there is still a feedback notch filter than has pretty narrow notches,imo. Built in limiters and VERY comprehensive x-over in this price range. Worth every penny!

[jamsmith]

Bump!

[AudioFields]

it totally depends on the rig and budget....if its a big rig, then you shouldnt need anything more than the processing (Lake, BSS, Etc). Smaller rigs could always use a DBX unit. The cheaper driverack works fairly well.

[dbbubba]

They can save your A$$ in some situations, but I have always found that a balanced and well set-up system can get a surprisingly large amount of gain before feedback.

I have barely ever felt the call to use a feedback suppression unit.
The rig I take out for half of the year is a 9kw Crown powered Renkus Heinz ground stacked rig.
It has a dBx 266 DriveRack in place of the tired old Renkus X-overs, but we did talk with Renkus and together we researched the parameters, so the 266 is pretty close.

Although my friend that I work with LOVE'S to mess with the 266 we have never turned on the feedback eliminator section.

We have a system curve set up with the 266's 31 band EQ and an Ashley 31 band at F.O.H. for extra tweaking. I am not wild about having TWO EQs, but the 266's EQ is really shaping the rig for an optimal room while the Ashley is there to tweak the awful rooms. That being said, I did the same gig and venues with only the 266 and the parametric in a Yamaha 01v.

Going back to your original question...
As far as over-all system EQ goes... you should be able to get a curve that has the rig sounding good in "good" sounding room and then tweak from there.
In general, all I ever have to correct is low freq. problems.

When using a line-array rig like our Nexo S Series all of the issues that arise when using a ground-stacked or conventional system go away.

Truthfully, the trick to gain before feedback is in positioning of the speaker boxes and EQ.

In the past I mixed a LOUD band where I had a vocalist WAYYYY out front in a mix when he was working the room on a wireless mic (SM58.)
This was up in the 114 db plus SPL range, too.
The guy was a good vocalist and smart enough to work the mic correctly.

[tINY]

The problem with auto equalizers (where is Ethan Winer when you need him?) is that they can only do so much. They also will only "correct" for the position the mic is in...

Where they would be really useful is setting the delays and phase on the different amplifier channels using some transient analysis. That is often hard to set by ear in big venues.




-tINY

[nickynicknick]

Originally Posted by jamsmith

What are your experiences using autocorrecting EQ for mains? Please indicate what size audiences/rooms you are working?

Never ever auto correct...not even sure what that is....I do not like feedback supression either....here's the thing....your best friend is a well balanced and properly set up rig....there are no real quick fixes... you have to learn how to get a rig in a particular room working for you...learn how to process a rig.....learn how and when to eq a room...and learn how to mix a band in any given situation.....re size of rooms/audiences......from the smallest club you can think of to a stadium and everything in between.

Using programs like Smart are necessary and great to get your rig set up....but always remember that your ears are your greatest asset. Use them for eq.

Nick

[tINY]

Originally Posted by nickynicknick

Never ever auto correct...not even sure what that is....I do not like feedback supression either....

You've obviously never had to run FOH and monitors on a band with sloppy technique who like the stage LOUD....




-tINY

[jamsmith]

Hmm. Maybe I should have been more forthcoming. I am very interested in the development of software to do some of the "chores" of mastering. During a discussion on auto mastering, I mentioned that the pro-audio world has tool that automate some tasks. This ME insists that all those products are junk and no one ever uses them. I know this to be the contrary, but I wanted to see where people are with it these days. As far as using your ear to set eq, I can see that in a pinch, but a pink noise generator and an RTA have been around for years and they can pin point problems immediately. I prefer to use the EQ for exactly what it stands for Equalization. The problem is that by the time you are tuning your PA it too late to call Ethan. That handy 31 band (real men use Parametrics!) can help tame the room well enough to get the show going. I then use my ears on the channel strip eqs to get the sound I want.

Now I wasn't even talking about feedback exterminators. I have seen those boxes work miracles. What amazes me is how rare I saw people use notch filters to tame feedback before these boxes came and and set them for you. A notch filter is WAY better then a graphic for the job

One trick I learned from a guy who came to my club to mix Foghat. Since the club was small and the band was loud on stage, the primary job that night for the PA was the vocals. The FOH guy took the lead vocal mic back to the sound board and adjusted my mains EQ for that particular mic.

Then to get max out of our monitors, they pulled everything out on the graphic from 200 and down completely.

[JimmyM]

Ya, usually people want their monitors really bright. Makes it much easier to hear without a volume that kills your ears and ruins the FOH sound.

I can see why a studio guy would say that. He's in a fixed environment without a lot of need to worry about feedback and poor sound from the room. An automated EQ gets you a lot closer to the mark in different rooms a lot quicker than tweaking a rack of graphics. Obviously you have to tweak them a little, but it's a timesaver and takes much of the guesswork out of it. Could we live without them? I should certainly hope so, but they're a nice convenience if you do a lot of one-nighters.

[jasonraboin]

I think what you are talking about is the Audyssey room correction system. It was developed for studio use but could be used live.

VST host for room correction

I use SpectraFoo and love it. It lets me look at the information and decide myself what to correct and what to leave in. Generally when I'm tuning, the room is empty. If the system automatically tunes the PA to an empty room, I will not be happy with the results when the room is full of people. I generally mix in 1000-5000 cap. venues that change a lot when full.

[XJR]

I've got the DBX Driverack but it's seldom used. In a fixed install it might be useful but to use it in different rooms every night means blasting pink noise through the PA while it decides whats wrong. It can only correct the EQ in the position it's input mic was in as well, it won't help with problems further around the venue. Plus the sound of a room changes as it fills up, especially in winter.

I've found that you can normally achieve better effect by careful placement of the stacks, use tilts on the mid \ highs to avoid the ceiling and adjust the power of each side of the bins to match the room rather than same gain per side. Most of the EQ is done per mic \ instrument on the channel strips, mainly subtractive and during the whole band soundchecking rather than solo'ed in isolation.
The above is in smallish venues, 200 to 500, PA is HK Actor DX with AH GL2400. Monitors are HK Darts with DBX 31 band graphics in line.

[odeon]

he FOH guy took the lead vocal mic back to the sound board and adjusted my mains EQ for that particular mic.

i learned this technique back in the eighties.
it always surprises me when younger engineers do not know how to tune a rig with the vocal mic.
as for the auto eq thing: i met a few younger soundguys that would set up their laptop and a measuring mic before even listening to the system. after getting everyone in the room scared by using high spl levels of noise they tuned the system flat. BUT: do you really always want a flat system? needless to say that the overall sound quality of their mixes were just bad.
the problem i see here is that the younger techs just don`t learn how to tune a system by ear anymore.same is for filtering sources right. like everyone is having a navigation system in their car now and noone knows how to read a roadmap.

[johndykstra]

Why do "purists" always hate tools that save time? Granted if I've got a rack of true 1/3 octave eq's, a killer x-over, and limiters for my mains sure I probably wouldn't use a driverack either. But a reality for a lot of small beer soaked punk clubs with mid grade mains hung by chains fed from QSC amps, and 231 eq's, the drive rack is a life saver. Especially since a typical house guy night around here means $100 and free beer, you can't get alot of solid #2 or 3 guys to back you up, so you train the nearist bass player with a drinking problem you can find. I guess what I'm getting at here is yeah, if I was a FOH guy at say the 9:30 club or the Metro, I'd diss auto eq's too. But I'm a weekend warrior with a sub amp I gotta Fonzie every once in a while, and I'm gonna take all the help I can get. No disrespect.

[oldgreensock]

If you have set up your rig corectly there should be no need for any eq other then at the channel strip. Your ears are better then ANY RTA.
Put in an awesome recording that you know (Paul Simon Graceland for me) and bypass or flatten your EQ and get it to rock using just crossover and amp gain settings. Then wait for the room to fill up and adjust acordingly.
Try Re-thinking anything that you "always" do EQ wise. If you find yourself saying "I always cut 200 by ten db" ask yourself if its out of habit or necesity.
Also if you make an EQ change and it doesn't fix or help then for the love of god put it back where it was and try something else. I have seen so many engineers make an eq cut with no result, then make another ect. untill the graph looks like pirates teeth, and its much worse off then where it started.
One last rant. If you consistantly have feedback issues at the FOH and your sustem is set up correctly YOU ARE MIXING TOO LOUD!!!!!!!!!!!!!!!!!!!!! It is amazing how many audience members you can gain by simply turning it down a couple of Db.

EAW KF760 line array (ten per side + subs) to PA on a stick.

[jamsmith]

Originally Posted by oldgreensock

If you have set up your rig corectly there should be no need for any eq other then at the channel strip. Your ears are better then ANY RTA.
Put in an awesome recording that you know (Paul Simon Graceland for me) and bypass or flatten your EQ and get it to rock using just crossover and amp gain settings. Then wait for the room to fill up and adjust acordingly.
Try Re-thinking anything that you "always" do EQ wise. If you find yourself saying "I always cut 200 by ten db" ask yourself if its out of habit or necesity.
Also if you make an EQ change and it doesn't fix or help then for the love of god put it back where it was and try something else. I have seen so many engineers make an eq cut with no result, then make another ect. untill the graph looks like pirates teeth, and its much worse off then where it started.
One last rant. If you consistantly have feedback issues at the FOH and your sustem is set up correctly YOU ARE MIXING TOO LOUD!!!!!!!!!!!!!!!!!!!!! It is amazing how many audience members you can gain by simply turning it down a couple of Db.

EAW KF760 line array (ten per side = subs) to PA on a stick.

You must mix outdoors all the time or you are blessed with being in good rooms. There is no way to "have set up your rig corectly" when it comes to an enclosed space unless you carry a truckload of acoustic treatment material. EQ is has nothing to do with how your rig is set up, well it shouldn't be, but that is another story. Some rooms just have horrendous acoustics. EQ is the method to deal with room anamolies, that is why is called equalization. You can have the smoothest most beautifully tailored PA in the world, if you put it in a crappy room it will sound like shit.

As to you ears being better than any RTA, what are you smoking? You can hear .1 db differences across all 31 frequency bands? The RTA and pink noise is not to make the room flat. The purpose is to start flat by accounting for room acoustics. In fact the better auto EQs have "virtually" 2 EQs. One is automatic and flattens out the room. The other is manual and allow you set the curve you want to hear.

To make this clear. The tuning the room is not making the system flat. Its making the room flat so the system can operate in the response you want it to an not have the coloration of the room effecting those decision. Of course this is not a perfect system and to do it really right would probably require multiple reference points, separate EQ for various array, and some mondo computing power. But at least we are on the way.

Even if you have a great ear, a bad night, and ear infection, a poor spot to set up the mixer, and a variety of the factor make tools like this great have when needed.

[tINY]

Your ears are different than an RTA.

An RTA will accurately measure the power level of each band with no regard for distortion, phase, or transient behavior.

...and it truns out that your brain will adjust to uneven frequency response over the course of about 5-10 minutes (it keeps track of the relative respose based on the acoustic space).



-tINY

[jasonraboin]

[QUOTE=odeon;1852793]i learned this technique back in the eighties.
it always surprises me when younger engineers do not know how to tune a rig with the vocal mic.


I cannot imagine why you would want to eq the rig with a vocal mic, unless you are the singer and your voice is the only thing going in the PA. How does the sound of MY voice through one particular microphone matter?
If I start with a "flat", phase coherent PA where playback sounds similar in headphones and in the room, I find that I need very little channel eq. to make it sound great.
You learned this technique back in the 80's because that's where technology was back then. You did not have powerful DSP available to you, nor did you have accurate ways to measure what was happening in the room that we have today.
That's not to say that you can't make a rig sound great with just a vocal mic, but it is not the way I would choose to do it.

[jamsmith]

[quote=jasonraboin;1854107]

Originally Posted by odeon

i learned this technique back in the eighties.
it always surprises me when younger engineers do not know how to tune a rig with the vocal mic.


I cannot imagine why you would want to eq the rig with a vocal mic, unless you are the singer and your voice is the only thing going in the PA. How does the sound of MY voice through one particular microphone matter?
If I start with a "flat", phase coherent PA where playback sounds similar in headphones and in the room, I find that I need very little channel eq. to make it sound great.
You learned this technique back in the 80's because that's where technology was back then. You did not have powerful DSP available to you, nor did you have accurate ways to measure what was happening in the room that we have today.
That's not to say that you can't make a rig sound great with just a vocal mic, but it is not the way I would choose to do it.

In a small club with a loud band, pretty much all that is going through the PA is vocals!

[nickynicknick]

Originally Posted by tINY

You've obviously never had to run FOH and monitors on a band with sloppy technique who like the stage LOUD....




-tINY

yes I certainly have and do...can't see how feedback supression is going to help. You'll get much better results by eqing for the given situation on stage. For example...I find in that situation that anything at 80 hz and below on stage is usless, so lose it completely and a lot of the time pulling 630 Hz can help vox cut on stage... as well keep everything except vocals out of the wedges (in a small club) if you can.....this is a very general for instance.....feedback supression sucks the life out of your monitor rig and makes it inefficient IMHO of course.

Nick

[nickynicknick]

To all the young guys shitting on the old guys......we are sharing stuff that you should listen to. You asked a specific question and you got a couple of very experienced answers. Let me reiterate.


1. Learn to use your ears.

2. Don't use Auto Eq

3. Learn to eq a room with your voice and a 58 (the only two things that will remain the same from room to room)

Don't get me wrong, your processor is an extremely important element in your PA set up....however this thread is about your ability as a FOH/Monitor engineer. Good luck boys.

Nick

[jamsmith]

I asked the question in the first place. I am am 47 and started doing audio in 1976. I not only know how to EQ a room with or without an RTA, I know how to build the EQ in the first place. I embrace new technologies especially, if means I can stop worrying about the system and put all my concentration into the mix. That is the same reason we spend to much time tuning the rooms in our studios.

As to feedback suppression, I have know idea what it is you used. Feed back is a fact of nature. If you set a system flat and increase the gain, you will reach a point where feedback occurs. If you have a resonance peak in the room that matches the one in your speaker, that will howl first. If you are fortunate to have enough volume, then you have nothing to worry about. If you need more gain, you will get feedback. A proper feedback supressor is a notch filter - a negative bell curve with a Q of about .05. This is surgical and will have very little effect on the system compared with the much wider Q of a graphic eq. The whole purpose of a feedback suppressions system is free up your graphic for shaping the sound.

================

For the record, unless you have the ability to hear and identify the frequency centers within dynamic program material the bumps and dips in the rooms response, you need an RTA with pink noise. This doesn't mean you need to make the RTA flat or a smiley face of what ever. It gives a quick and accurate picture of the room. You use this to make informed decisions. If you have that accurate an ear, you need to be charging $500 an hour doing mastering.

[nickynicknick]

Originally Posted by jamsmith

I asked the question in the first place. I am am 47 and started doing audio in 1976. I not only know how to EQ a room with or without an RTA, I know how to build the EQ in the first place. I embrace new technologies especially, if means I can stop worrying about the system and put all my concentration into the mix. That is the same reason we spend to much time tuning the rooms in our studios.

As to feedback suppression, I have know idea what it is you used. Feed back is a fact of nature. If you set a system flat and increase the gain, you will reach a point where feedback occurs. If you have a resonance peak in the room that matches the one in your speaker, that will howl first. If you are fortunate to have enough volume, then you have nothing to worry about. If you need more gain, you will get feedback. A proper feedback supressor is a notch filter - a negative bell curve with a Q of about .05. This is surgical and will have very little effect on the system compared with the much wider Q of a graphic eq. The whole purpose of a feedback suppressions system is free up your graphic for shaping the sound.

================

For the record, unless you have the ability to hear and identify the frequency centers within dynamic program material the bumps and dips in the rooms response, you need an RTA with pink noise. This doesn't mean you need to make the RTA flat or a smiley face of what ever. It gives a quick and accurate picture of the room. You use this to make informed decisions. If you have that accurate an ear, you need to be charging $500 an hour doing mastering.

You, my friend, are wrong on all counts. Very unfortunate that some young guys may listen to your advise. BTW this is not new technology by any stretch. Why would you ask a question if you think you already know the answer (which you don't). It was a very good question actually and you got a couple of very good answers from people with real experience. You obviously do not know how to eq a room if you feel that an RTA will do a better job period. There is no point in arguing with you further, but I would like to say that anyone who wants some good info on this topic shouldn't listen to Jamsmith. I'm not saying that to be mean...I'm just sayin'....and...yes my ears are that good...and...there are lots of people with better ears than mine.

Nick

[Jim vanBergen]

Without getting involved in the pissing contest, I'll throw in my $0.02 worth of perspective and try to leave it at that.

I've been doing this professionally for 20 years. I have mixed FOH or monitors for several resume' pages worth of bands, from jazz acts to jam bands to classic rock to modern music of all types, including hip-hop and rap. I have mixed stadium shows of 100k people from time to time, and am the head of audio for an annual outdoor festival whose audience is standardly 25,000-50,000 people. I am accustomed to working in arenas that seat 6k-10k people and theatres like Radio City or the theatre at Madison Square Garden that seat 4-5k, as well as intimate clubs that only house hundreds or a few thousand. I am VERY fortunate to have never had to do the club work with lousy gear for $100/night, and since 1995 I have turned down too many fulltime touring jobs in an effort to stay close to home where I get to do a lot of recording and broadcast work, which gives me great pleasure as an engineer.

1) I have, so far in my career, found auto-correcting EQ to be worthless, because it does not compensate for all the parts of a sound system; Nor does it understand the interaction of system elements, plus the artists, stage volume, and audience. I don't like feedback supressors because they can over-correct and even notch out a note that is not feedback. I dislike 1/3 octave EQs because they cause phase shift. I concur with the statement that the BEST thing you can have is a well-designed, well-aligned system that works together... and if you're not the FOH mixer, then you provide that person with the stereo EQs of their choice to 'tune' the system to their liking once it is aligned to work together as systems must be, working as a single system of many parts such as front fills, mains, subs, and outer fills, plus any delay stacks or area fills, as a working whole. Once the system parts are aligned, I can sometimes leave the EQ punched out, historically much to the humor, shock or chagrin of other engineers who then hear a well-aligned system that is even and equally efficient across the spectrum.

2) I am in the process of trying out a new device called ConEq, or CONEQ, which is an automatic equalizer. So far I have been impressed with what this can do for nearfield studio monitors. This process may change my mind & attitude on the above statement for live sound. I have done some promising tests but I'm going to leave it at that for now.

3) For live sound reinforcement, I think that SIM3, Smaart, and similar dual FFT measurement devices are the BEST way to see what components are doing in a room or environment, and once a system is aligned, to see & adapt (correct, if you want to be that bold) how the system changes during a show with an audience. Making these adjustments well takes a huge amount of experience and knowledge of physics and electrical engineering as well as acoustics.

4) Currently, I fail to see how an automatic mastering software could take into consideration that which a proper mastering engineer does "beyond EQ and compression" - which is to look at a project as a whole, and consider what, if anything, needs to be done to unify the project from a series of songs into a cohesive whole, and by which, makes himself an invaluable part of the creative process of creating an album or disc. Perhaps you know something that will change my mind, and I wish you luck in your endeavor. It is an exciting concept, and maybe you are on to something.

My respect to all on this thread- again, I'm not here for the pissing contest, just to try and add a different experience and perspective to the conversation.

Hope this helps!

Regards,

Jim van Bergen

[nickynicknick]

Originally Posted by Jim vanBergen

Without getting involved in the pissing contest, I'll throw in my $0.02 worth of perspective and try to leave it at that.

I've been doing this professionally for 20 years. I have mixed FOH or monitors for several resume' pages worth of bands, from jazz acts to jam bands to classic rock to modern music of all types, including hip-hop and rap. I have mixed stadium shows of 100k people from time to time, and am the head of audio for an annual outdoor festival whose audience is standardly 25,000-50,000 people. I am accustomed to working in arenas
My respect to all on this thread- again, I'm not here for the pissing contest, just to try and add a different experience and perspective to the conversation.

Hope this helps!

Regards,

Jim van Bergen

Nicely put Jim. That was a fairly big piss though! Good job!

[tINY]

Originally Posted by nickynicknick

...if you think you already know the answer (which you don't). ...You obviously do not know how ...There is no point in arguing with you further...shouldn't listen to ...yes my ears are that good...

F'in Canadians...

Sure, you can do a lot of things better yourself or by design. I can't remember the last time I had a bunch of time to waste ringing out the monitors on a small gig where I had to run FOH and 3-4 foldbacks.

Properly used, the FBX is a nice, time saving tool. You can dump the notches occasionally or only lock in the 2-4 that show up before the band starts.

That leaves more time to point the guitar amp somewhere other than right into the lead vocal mic, repatch arround the bad snake channel, or figure out which comp/gate in the clubs rack is cross-patched and making things sound weird.

Must be nice to live in a world where you don't have a bunch of other things to get fixed in a 15 minute sound check.....



-tINY

[nickynicknick]

Originally Posted by tINY

F'in Canadians...

Sure, you can do a lot of things better yourself or by design. I can't remember the last time I had a bunch of time to waste ringing out the monitors on a small gig where I had to run FOH and 3-4 foldbacks.

Properly used, the FBX is a nice, time saving tool. You can dump the notches occasionally or only lock in the 2-4 that show up before the band starts.

That leaves more time to point the guitar amp somewhere other than right into the lead vocal mic, repatch arround the bad snake channel, or figure out which comp/gate in the clubs rack is cross-patched and making things sound weird.

Must be nice to live in a world where you don't have a bunch of other things to get fixed in a 15 minute sound check.....



-tINY

I hear you Tiny...I've done (and still do) many many shows under the same circumstances...I've always felt that FB supression made it worse....mostly because it takes out frequencies that I don't want it to, thereby taking away the efficiency of the monitor rig...the 15 minute changeover is difficult and I've learned to really prioritize during that time...(In small clubs)#1 is taking everything out of the monitors that isn't a vocal...the loudest thing in everyones monitor is there own voice...this takes about 5 minutes.....then 5 minutes of line check....then 5 minutes of scrambling to find where the F-ing Bass DI is in the patch and making sure the mics on stage are where I want them...then away you go let the band ask you for xtra stuff after the first song....most of the time they won't esp if they can hear the vocals clear.....and yes I love my country.... and yours too....seen lots of both.

Nick

[jamsmith]

Originally Posted by nickynicknick

You, my friend, are wrong on all counts. Very unfortunate that some young guys may listen to your advise. BTW this is not new technology by any stretch. Why would you ask a question if you think you already know the answer (which you don't). It was a very good question actually and you got a couple of very good answers from people with real experience. You obviously do not know how to eq a room if you feel that an RTA will do a better job period. There is no point in arguing with you further, but I would like to say that anyone who wants some good info on this topic shouldn't listen to Jamsmith. I'm not saying that to be mean...I'm just sayin'....and...yes my ears are that good...and...there are lots of people with better ears than mine.

Nick

Yeah really, what the **** where those electronics engineers thinking when the invented the RTA? I mean seriously, how could you possibly think companies like Klark-Technik could make products professionals use? And why indeed would those amatures at companies like Showco and Clair brothers have then anyhow? I mean who has any respect at all for those clown touring the arena across America?

But don't listen to me. I've only been doing this shit for 30 years. I never handled a board larger than a PM-4000.

And by the way, you don't use a RTA to EQ a room, you use an RTA to see the acoustic anamolies. Perhaps if you had a clue what professional equipment was used for you wouldn't be so perplexed. And learn to read. The question was directed toward other professionals who actually use autocorrection tools to discuss their experiences with these tools, not to amatures with their 58s to put in their 2 cents.