Looking for Basic System EQ Suggestions

[Rickisan]

Err... umm... very basic. : )

Looking at how to best EQ the small system pictured below. Not pictured are two Wedgehorn 8's. It is a Mackie 808s and an Behringer FBQ3102. The Mackie has dual amps and ability to accept the Behringer EQ in to the signal path....

I've read here for many hours and now would like to make this meager group of stuff sound as best as possible until more sophisticated gear can be acquired.

Intended use is mostly vocal and light guitar keyboard PA sound reinforcement. Specifically Shure SM-58 mikes, electric guitar, and Roland xp-50 keyboard.

I have RTA on the smart phone, a laptop pc, and basic knowledge of what I'm trying to do but not sure where to start. Should I make a Test Tone CD with freqs at center of EQ sliders, should I buy a db meter, a calibration mike, REW software... etc... not sure what to do first. Thanks, Rick



http://hungrypoint.com/pictures/misc_pi ... bq3102.jpg

[Bill Fitzmaurice]

Get rid of the EQ, get a DEQ2496. It does all the work for you. You can use one channel for the mains, one for the monitors. BTW, what's the second mixer for?

[Rickisan]

The second mixer is simply a back-up for the bigger one. Just something we can plug our vocal mikes in to and make some noise in case the Mackie quits in the middle of a job.

I will look at selling the EQ and replace with the DEQ2496.

Thanks Much

[SeisTres]

To be honest (being the lazy person I am) I would simply use the mixer 9band eq for mains and monitors and skip the whole 31band graphic. The 9band does a well enough job of eq'ing jacks and if not running subs and crossing over, the graphic is just a PITA. My favorite system (and possibly the one that got the most use) was my four jacks and my powered behringer mixer. That's it; no extra power amps, no extra eq, no subs, no crossover.

The easiest way you can eq would be to download an rta program (if you have an iphone, try jl audio tools, it's free and is the best one i've come across), run the rta at octave resolution and then just start moving sliders until it's relatively flat. If you wanna add the 31graphic, simply follow the process i just described and use higher resolution rta (1/3octave).

Also, have bink's audio test cd handy as it has just about all you need to set up your system.

For down the down, and true measurement mic along with auto rta tool works wonders.

[Bruce Weldy]

With that system and what you want to use it for.....I'd do the following:

Plug in a mic.
Set the channel flat
Start talking into the mic (real words, not "check 1 2")
Adjust graphic on mixer until it sounds good.
Start singing into the mic
Adjust a little more until it sounds better.
Play gig.

No analyzer can tell you any better than your ears how a vocal should sound. Now, with subs and putting a lot of content through the system - that's another story. But, with your main concern being vocals - tailor the sound to best compliment them. The other instruments will be fine if you nail the vocals.

[Bill Fitzmaurice]

No analyzer can tell you any better than your ears how a vocal should sound.

True, but it's a lot easier if you start off with flat in-room response. I use my 2496 to get that in about ten seconds, as opposed to fifteen to thirty minutes doing a manual RTA and then adjusting, and readjusting, and readjusting the EQ until it's right. Then I adjust the individual channel EQs and the on-board EQ to get it sounding the way I want it, which usually doesn't take much after the system is flat in-room.

[Rickisan]

Thanks for all the helpful replies. I will start with some basic testing...

Run the binks cd and try some RTA with the JL app on the iPhone.

For raw approximate testing I can run the test cd through the laptop straight in to the mixer and then use the JL RTA on the phone to get a rough idea of where to cut and boost on the 9 band eq.

Does this sound like a place to start? I would love to get real techinical with db and voltage levels etc... but this will all come in time... along with more sophisticated equipment.

Thanks again for pointing me in the right direction!

[Grant Bunter]

If I didn't have RTA, I'd just "mirror image" the SPL charts as much as I could with the onboard 9 band and write that down as a baseline to start at with every gig.

As far as measuring voltage goes, if the head has it, use a 1/4" jack without a lead on it (or an speakon plug with the end cover off) and a multimeter to measure.

Based on Mackie's 808s specs, maximum output for 2 cabs in parallel would be 42volts

[Rickisan]

Using the 1/4" jack to measure voltage. What signal should be going in to the channel input? If any? Thanks

[Grant Bunter]

Pick a number on the lower end of the scale for the cab, say 80Hz.
If you broke in your drivers with a tone generator, use that again, set to 80Hz.

Plug that into a channel, set the gain on that channel so the Mackie is just below clipping on the channel and the main output, then measure.
Do not have any cabs connected to an output...

[Rickisan]

I finally got this going... running a 80hz tone out of Audacity. Out of PC through the headphone output to an RCA adapter to a 1/4" in to a line input on channel 5 of the Mackie.

I put everything flat 9 band EQ and all 3 bands on the individual channel. No
EFX, no 75hz high pass filter, no compressor etc.

Maxed Master Volume, maxed the two input volumes on the channel. All leds lit in to the red. Reading 88.4V AC on the left channel and virtually the same voltage on the right channel.

When the Mackie Compressor button is engaged the voltage drops to approx 42 V.

I guess my question now it how do I know when the amp is clipping. : ) I think I know enough to say it surely isn't putting out 90V. So testing refinement is in order? Rickisan

[Grant Bunter]

I finally got this going... running a 80hz tone out of Audacity. Out of PC through the headphone output to an RCA adapter to a 1/4" in to a line input on channel 5 of the Mackie.

I put everything flat 9 band EQ and all 3 bands on the individual channel. No
EFX, no 75hz high pass filter, no compressor etc.

Maxed Master Volume, maxed the two input volumes on the channel. All leds lit in to the red. Reading 88.4V AC on the left channel and virtually the same voltage on the right channel.

When the Mackie Compressor button is engaged the voltage drops to approx 42 V.

I guess my question now it how do I know when the amp is clipping. : ) I think I know enough to say it surely isn't putting out 90V. So testing refinement is in order? Rickisan

Cool!
You're getting closer.
Adjust like this.
With the compressor off:
If the channel strip has a clip light (red LED) adjust gains until the clip light barely flickers.
Like maybe once or twice through an entire song as an example.
Then adjust master(s) so they barely flicker in the reds
Same same.
Check your voltage then.
Tweak accordingly until you get your max output.

Then drop the tone to say 40Hz, see if anything changes.

If not, from this day on, that's how you set up your Mackie.
Regardless, it helps heaps with a mix to have the channel strip barely tickling a clip light.
Less distortion.

As a side note:
When you turn on the compressor, does the masters LED's stop going into the red?