Jack Lite 12 with Piezos… EQ Tips

[nola50]

We will have this pair indoors at their first event.

The amp is a Crown XLS 1500 from a QSC TouchMix 16.

Methods, ideas, comments all welcome!

[Bruce Weldy]

EQ the main outputs of the TouchMix first. It will make the adjustments on the individual channels easier. Are you running subs? Putting instruments in the mix or just vocals?

[Seth]

Hey nola50, happy to help. Please, a little more about your expectations, the venue size, shape, stage orientation, and what source and/or instruments you intend to amplify. Are you calling out BINGO numbers, Karaoke, DJ, or is it a 7 piece band with DI's and a fully mic'd drum rig?

[Grant Bunter]

Hi Nola,
You haven't mentioned any processing.
If using a processor, I would either do a rough tune in the processor EQ, or do as Bruce suggested and use the Touchmix EQ.

To get somewhere near "flat" ie take the bumps and lumps out of the J12 response chart and using the mirror image technique, I would suggest dropping EQ from 250Hz to 600Hz by about 2.5dB, increasing 5 and 6K by 2.5dB, and dropping 7 to 12K by 5dB. That gets you into a ballpark where you know anomalies are now from the room, not the cabs.

Adjust for the room, then tweak by ear.

This method will work regardless of content being played through the cabs...

[nola50]

Room is hard sided, brick floor, probably 20 x 20 with vaulted ceiling. No subs. Keyboards, guitar, bass, electric drums.

Should I use the Room EQ function in the TM 16?

[Grant Bunter]

Room is hard sided, brick floor, probably 20 x 20 with vaulted ceiling. No subs. Keyboards, guitar, bass, electric drums.

Should I use the Room EQ function in the TM 16?

I don't know that unit well enough to say for sure.
I would set EQ as I suggested before, then use Room EQ.

In my mind, if you do Room EQ straight up, it's trying to EQ your gear and the room at the same time, as doesn't know what's what, just what it measures...

[Bill Fitzmaurice]

Room is hard sided, brick floor

You have my condolences.

[nola50]

Bill... I totally understand... this is not the best place. Maybe there will be lots of people and it'll gt better!

[Bruce Weldy]

Bill... I totally understand... this is not the best place. Maybe there will be lots of people and it'll gt better!

When dealing with really reflective surfaces, there are some things you can do with speaker placement to make things better. The more direct sound the audience hears (verses reflected sound off the walls, floors, etc) the better the clarity and the lower volume you can run with the same perceived loudness.

If the audience is sitting, try to get the speakers angled down toward their ears. If you can't angle 'em, then lower 'em. Too many people raise their speakers really high thinking that they are hitting more of the audience, but just makes the sound horrible for everyone.

Also, try to never point the speaker directly at a wall across from it. If you have to, put more space between the mains and point them in - keeping the energy on the audience and off the side walls and back wall as much as possible.

If you can set up in a corner and aim toward the opposite corner - do it. That lets the reflections hit the walls at an angle and move to the back of the room and hopefully stay there and not bounce back at you.

Doing these things will let you create a sweet spot toward the front and middle of the room. It won't be as loud for those in the back - but at a higher volume, it's gonna' sound like crap to them anyway.

[Seth]

Room is hard sided, brick floor, probably 20 x 20 with vaulted ceiling. No subs. Keyboards, guitar, bass, electric drums.

Should I use the Room EQ function in the TM 16?

Since you're in Louisiana, I'm going to assume 20x20 is feet. Basically the size and shape of a standard 2 car garage? People in the space will absolutely help in keeping the reflections down. Without people in the space, a large rug would help too. If it's not a public commercial space, even blankets, towels, laundry, etc. strewn about will help in getting the system tuned until you can get some bodies in there. But, it's not entirely necessary. Most venues have their own unique challenges to overcome. Just gotta do the best you can with what you've got to work with. Vaulted ceiling will be working in your favor. By the standards of what people are used to seeing, it's a little unconventional... but, I would try vertically arraying the cabs, one atop the other, in one corner aimed diagonally across the space, bottom cab just above head height.

I'm not familiar with the functionality in the amplifier you're using. If it has DSP with EQ, I'd do your base system EQ in the amp and use the mixer EQ to fine tune for different venues. If the amp doesn't have EQ functionality, there's nothing wrong with just using the output EQ in the mixer. I have only put my hands on a Touchmix 16 one time and all I did was simple mixing. I didn't do any channel setup and never got the chance to really delve into all of it's functionality. I assume it's at least on par with the functionality of Behringer's XR12/16/18 or any of the PreSonus offerings. It should be possible to use a measurement microphone and be able to see the system response RTA directly with the mixer. Alternately, you can get an inexpensive "calibrated microphone" that you can use with your phone/tablet and free apps.

Without any sort of measurement device, you can do what Grant said and achieve a quick rough-in EQ by using the Jack 12 response chart and dial in a mirror image, bringing the peaks down and the lulls up in an effort to equalize the response. You'd still need to do a bit of it by ear due to any artifacts the room imparts. You can get some very decent results with this method. Then fine tune each instrument channel EQ to taste.


If you choose to take the route of using a measurement device, I've had good luck running pink noise through the system and adjusting the EQ until the RTA looks somewhat like this;

Since you're not running subs you're not going to want to follow that response below 60, maybe 70Hz. Matter of fact, if you have the ability, you may want to apply a 65ish Hz high-pass filter on the mains.

You're also going to want to put a high-pass filter on the individual keyboard channel, somewhere in the neighborhood of 150-200ish Hz.

Keyboards, guitar, bass, electric drums.

Are all of these DI'd, without instrument amps?

[Bruce Weldy]

Since you're in Louisiana, I'm going to assume 20x20 is feet.

Do not assume that......it could be 20 Po' Boys x 20 Po' Boys.

[Seth]

You're right. Good point. Could just as well be 20 alligators or 20 crawfish.

[nola50]

They are DI'ed from their amps. I use it to record and feed my wireless IEM. No one else uses IEMs.

[Seth]

They are DI'ed from their amps. I use it to record and feed my wireless IEM. No one else uses IEMs.

So, keyboard has it's own amp, guitar has it's own amp, bass has it's own amp, and electric drums has it's own amp... and they're all DI'd for recording and monitoring, but not run through the main PA? Or are they all run through the PA too? Is the primary amplification of each instrument to the audience the PA or the individual amps?

[nola50]

Only vocals go through PA. Old school guys..