Help with EQ'ing FOH
Dubravac
Posts: 7
Hello, i'm new to this forum and first let me say that i'm really learning alot from some of the previous threads, especially on gain structure. I play in a 6 piece band ... we have EV QRX series speakers (115/75 tops and 118S subs) ... tops go to one QSC amp and the subs to another. We were recently considering purchasing either a new 223XL X-over and 1231 EQ or go with the Driverack PA. As we're still learning how to do sound properly, we're leaning towards the 223XL and the 1231 EQ, but i'm open to your suggestions lol.
My question is, how do you guys go about EQ'ing the FOH ?? Obviously this is all post gaining and after ringing out the monitors. Is there a good method anyone uses to getting the best sound from FOH by adjusting the EQ ??
I really appreciate your help and expertise, thank you !!
My question is, how do you guys go about EQ'ing the FOH ?? Obviously this is all post gaining and after ringing out the monitors. Is there a good method anyone uses to getting the best sound from FOH by adjusting the EQ ??
I really appreciate your help and expertise, thank you !!
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Comments
"Graphic EQ's are not the best tool for any off these, but are usefull.
Generally speaking, never boost any frequencies, only cuts. Your best bet is to set up in the room and turn on all mics and squeal (ring) out the system. If you are not familiar with the process,
one trick is turn the system up until feedback starts and reduce the volume until it stops. Then, increase each eq fader (one at a time) until it starts to ring.
Make a note of the +db gain, then return to -0-. Do this through all faders. Any filters that fedback with 3db or less, reduce those to -6db and leave them. Any that were +4 to 6db, reduce to -2 or 3 db.
Increase the gain knob on the EQ by +3db and check the mics for volume. Continue if neccessary."
The part highlighted in blue ... if you reduce those frequencies that feedback to -6db, you've basically cut that entire frequency out no ? As i look at the dbx 1231, the lowest you can go is -6db. I thought cutting out a frequency completely was wrong.
Thanks again !!
Yes...we do it with the driverack. Those other pieces will only muddie the issue. Take charge of your sound... get a DR..
Gadget
The 1231 is 6 or 15db range selectable. The 6db is for very precise work. You would use the 15db setting. (Another reason to get a DR is the feedback filters are 1/5, 1/10, 1/20, & 1/80 octive, while a 31-band is 1/3 octive.)
The "BLUE" thing. Remember, you are JUST BELOW the feedback volume. The increase is to find which freq will feed back if you increase the volume. For example, if you go through all bands and 500 & 12K each feedback when you boosted their fader to +6db, but no others caused feedback at that level, when you reduce 500 & 12K to -6db you will gain 6db of system volume before feedback.
Buy the Driverack.
DRA
You know, i really do want to get a driverack ... i was really reading into the driverack pa+ for my band, but i'm in all honesty intimidated by using it. I don't consider myself an expert at doing sound so i do get a bit intimidated by using it. It's strange to me ... some people are so dead set for the driverack and some so not for it so i'm at a crossroads at what to do. I like the Auto EQ feature, but the more i read on it, the harder it looks to achieve good equalization with it. I don't know, maybe i'll just keep reading on about it and decide if i wish to buy one or not.
By the way, how would i set it up ? The speakers and amps i have are not in the wizard ??
I have EV QRX 112 tops, 118S Subs ... and amps are QSC PLX3402 and QSC RMX2450.
Read up there.
DRA
PS - I never had one until I got one either.
:shock: WHAT... HEAVENS NO!!! :shock:
That's the method for ringing out the mains not system eq!
System EQ and ringing out the system are TWO COMPLETELY different things. System tuning is the process of getting the system so that it has equal energy for all frequencies within the frequency range of the speakers...
Ringing out the system is a way to determine gain before feedback in a room...
I would NEVER ring out a system to tune it, and using the driverack and getting the system tuned properly and flat will have the gain before feedback good enough that I have not had to RING out a system in a decade or so...
The thing is that the people that are dead set against it are usually those that don't understand it, or it's tool set... or that are after a different product, usually with a much steeper price tag... like Lake, or XTA..
If you can follow directions the driverack will elicit huge improvements in your system... the fact that your speakers are not in the driverack is no problem what so ever... we can easily get you the HPF/LPF and slopes... in fact we have done so thousands of times! the ONLY thing a preset is.. is a starting point. In fact the FAQ section her I have provided all the info you need to do everything for yourself... and the START HERE thread in the READ ME FIRST BEFORE POSTING section tells you step by step how to set up your system and tune it and set the gain structure properly...The auto eq has been de-mystified and the new DRPA+ has a nearly foolproof room eq that WILL make your system sound better than without it...and you'll have better gain before feedback, better clarity, more intelligibility, less rumble and better crossover region clarity and less interaction...
you really won't believe the difference...do you know anybody @ a GC or music store that would let you try one? but be warned.. once you have tried it they won't be able to pry it from your dead burned fingers
In your step by step guide, it shows how to setup the driverack, then you do gain structure ... however, in the driverack wizard, in auto-leveling, it asks at what point your amp gain is at. How are you too set that point if you haven't done your gain structure yet ?? Would it be ok to do your amp gains using the method you have, then go and setup the driverack ??
Just 2 more questions ...
1. In graphic eq setup, what is 'dual mono' and 'stereo linked' ??
2. What are filters in the AFS used for ? Can you put one of every input on the mixer you have ?? So lets say you have 3 vocals, guitar, bass, keyboard, drums (3 mics) ... you can have 9 filters ?
This is my setup to give you an idea ...
Speakers ... EV QRX 115/75 tops ... EV QRX 188S subs ...
Amps ... QSC PLX3402 (subs) ... QSC RMX2450 (tops) ... left and right from tops to one amp, left and right from subs to the other amp ...
We play in 2-way Mono ... venues we typically play aren't parge places and we really have no need to pan anything, so we go Mono which serves us well.
I really appreciate your help and your expertise ... i'm really learning alot here and it's great !!
Much Appreciated !!
The DRPA+ is good enough... and if you had dug a little deeper you would see that on axis 4-6 feet out aimed at the speaker will work as well.. this incorporates what is called the proximity effect where the sound directly from the speaker makes any reflected/returned sound FAR below the direct sound from the speaker.
One of the reasons they built the DRPA+ was that there was so much confusion when doing a tops/subs, or tri-amp system for instance..if you simply cranked the amps and set the crossover the tops might overpower the subs or the subs might overpower the tops and then the auto eq would need to try and restore the balance using the gains of it's individual GEQ bands, and you might see an entire band of frequencies (like everything between 20 and 180 hz) TOTALLY cut or boosted ..(there are other things that can cause this but lets stick to the setup first...) So the sequence is... select stereo/mono ... select speaker tops... select speaker subs... mono/stereo... select top amp... set the clock position on the amps to ______this position... same with the sub amps...
Next we have the auto level, where we set up the balance of the system...simply follow the prompts on the DRPA+ screen...
All of the above was done manually with the first generation of driverack... so the new PA+ helps you do it the right way if you don't know what your doing...
Then you auto eq and set the system up flat and create a flat preset in the memory...
Dual mono allows you to do a number of things...(note that in dual mono you will be required to do each side of the PA separately....as in auto eq ) say you have a room that is seriously different on one side than the other.. you can eq each side separately...you can also run mono FOH and a monitor mix on one driverack, and in this way auto eq each input as a separate entity...stereo is just that... one pass with the autoeq for both sides...
No...tha'ts not the way it works...
Remember in the first part of this post when we talked about setting the system up for flat response? This gives us the best gain before feedback, and insures that all frequencies are equally represented so that you don't have to over eq your individual channels to get things out in the mix...
So when it comes to the FBX it has 12 filters...these can be either fixed or roaming... so we set up the system, monitors and all... we get everything set up as best we can and this includes the setup we did, and includes getting all mics up and running and set up as we would like them in the mains and the monitors... NOW we pull the main faders on the mixer and engage the FBX...as we raise the main faders PAST the point where we set the system up... we are changing the response of the speakers as we exceed the point we set them (the louder you get the more the response curve of the speakers changes) so we want 6 fixed filters which we are setting now... as we raise the mains faders the system gets louder and louder...(yes there is enough sound in ambient noise to excite the system...) the mics start to "hear" the speakers... the frequencies that the system hears first will start regenerating...(feeding back) and the FBX will "catch" them and notch them out with as narrow a filters as can do the job...then as we go louder, the next frequency starts to regenerate and is caught by the second filter... meanwhile the FBX is monitoring the first feedback frequency and making updates to it as well as frequency#2... and so on till we get all 6 filters filled or you exit the process.. I seldom get more than 2-3 filters to set before I am nearly maxed out .
remember the 6 roaming filters? they are there to catch anything that happens during the show... like idiot singers hanging from the light bar in front of the speakers and screaming his lungs out...
Here you can place one monitor mix, and the mains on the 2 channels of the driverack.. and you WILL NOT BELIEVE the way the monitors will sound with the driverack on them...and they will get LOUD... MUCH louder than before... if done properly...
G
1. I still don't understand the process of setting up with the wizard. How are you supposed to set the clock positions for your power amp gains, when you have not done gain structure yet ? Do you just put something in randomly then adjust it later .... and how are you to select your tops and subs when they are not in the wizard ... i have EV QRX series speakers ... and also my power amplifiers are not in the wizard list as well.
2. I'm trying to find the Auto EQ section you mentioned where you place the rta mic 4-5 feet away on an axis ... do you have the link to that by chance ??
You're the man Gadget ... thanks again for all your help.
As far as I'm concerned putting the presets in the wizard is a crutch...all they do in a tops/subs config is set an HPF/LPF and a safe HPF for the subs...If your speakers are not in the list enter "custom" and move on... further, the clock position on the amps is also dubious info...for this exercise we prefer to use the gain structure method for setting the amps input sensitivity as detailed here:
viewtopic.php?f=61&t=959
In the setup section..where we use the gain structure method to set the amps sensitivity to determine the clip point...
You know, I have seemingly written that a thousand times I guess I didn't get it into the FAQ's? :roll: the thing is, get the mic close, but not too close so it hears the whole speakers components, but close enough to make any reflected energy so far below that of the direct field that it has no affect...I have remedied that with a blurb in the Auto eq FAQ's...
Gadget