I have a question about EQ'ing for mains

[slap-a-da-bass]

Some background...

I play in a 5 piece 80's/90's pop/rock band. Most of our gigs are small outdoor/beer garden stuff or smaller indoor bars. Usually no more than 150 people in either case, and I would consider us to play at lower volume than most bands.

I just recently bought a pair of QSC KW181 subs. Since getting the new subs, I've been asking myself if I should get the K12 or KW122 tops. So, with that in mind I've been comparing other tops I own, RCF art 312a's & the EV elx112p. When I compare these two speakers to what I think a specific recording should sound like, the EV's sound a touch nasally, with some high end sparkle missing. The RCF sounds crisper, but is lacking some mids when used with a sub, specifically what frequency's I couldn't tell you, which is where my problem comes in.

So my question. Is there a general EQ curve you like to follow for live sound? A little more low end? roll some highs off? I find when I listen to many local bands in similar venue's, I think the mix sounds muddy/dark, & not nearly enough highs or air under it. Last night I went to a Jazz festival, & I thought the instruments sounded really good, but the vocals sounded a little dull. Also it wasn't noticed in the vocal during the songs, but the speaking was awful. Lots of problems with S & P's, and again muddy and not enough clarity to completely understand what they were saying.

What area of the EQ should I be focusing on for a live mix? maybe 60hz-5K? 7.5K? or is most of the tone shaping much lower than 5K? I've used a friends RTA & I find it makes adjustments with a swing of +/- 10db. & when I compare the corrected tone with bypassed EQ, it sounds like the change could be an improvement, but it sounds drastic. Also noticed at louder volumes the high end gets harsh & fatiguing to listen too, again this is with recorded music.

Can I get some opinions?

 

[Hactar]

When I'm EQ'ing a live system, I'll start out by listening to recorded content, and making "broad" EQ adjustments, i.e. putting in gentle dips for boomy/harsh, etc. These adjustments are broad and can involve any frequency.
Then I'll ring out the system.
After that, during the show, there may be adjustments that need to be made, perhaps rolling off highs, etc.

I suppose in answer to one of your many questions, "What area of EQ should I be focusing on for a live mix?" my answer would be "All of it."
Doesn't seem very helpful, I know, but that's just how things are

However, generally it is not necessary to put complex curves in the bands above 6k unless there is a specific feedback-prone frequency up there.

 

[Big_Daws]

how i eq a system is to ring it out, stick a mic in the middle of your room (if you have an RTA mic then use it, in a pinch just use the most sensitive mic you have, not ideal but can work out well) then from there just pull out the frequencies that are giving you the problems.

then i will generally play track through (with the EQ on the board flat) it to see what the PA sounds like. even then i will do most of my eq'ing on the console rather than touching the 31 band. whats the point in adjusting what you have adjusted.

i sometimes (most) will use my iphone app (JL AUDIO and its free) to help me pick frequencies i can't find. even though most people will say not to use an iphone for this and for the most part i agree, i find this a most helpful guide.

 

[Barisaxman]

Probably the biggest thing you can do is get to know how your rig sounds in as neutral an acoustic space as possible (for most people outdoors in an area with as little reflection as possible). It's basically impossible to create a "general eq" for any system without hearing it. If the above is not possilbe, get in the venue early and listen to the system with program material that you are familiar with. Generally most of my big changes in house EQ are to clean up the lower frequencies, specifically around the crossover point of a system using subs (80-150hz). This where a lot of the mud and boom reside. I have an EQ curve set up in my processor to flatten the system, and can usually tweak to the room after that. You can use all of the tools in the world to help, but the number one tool is your ears. You should know what you want your system to sound like and adjust accordingly. I try not to use system eq to flavor the FOH sound...rather any tweaks are to individual channels/sources to get the overall sound that I'm after. I essentially want a blank pallet to start at FOH and work each individual instrument/channel to get the sound I want.

 

[Keithwah]

A good poor man's method would be to get yourself a sample of pink noise. Rip it or download it to your jukebox/ripping software or use Audacity and burn the sample at the highest bit rate possible or.....download it in wav form for a purer audio sample. Either way...get it to something (CD, iPod, etc) in order to run it through your rig. Via your or somebody else's smart phone, download an RTA app.

Using your RTA app, star running your pink noise sample. Look at the general frequency curve from the center of the room (and hopefully mix position), use your EQ to balance the freqs DOWN to where they are all even for the most part. Use your EQ to ONLY cut from the 0db mark....don't boost frequencies. If you have a "hole" around your crossover point feel free to consider upgrading speakers. Otherwise...add freqs in small doses. You have now EQ'ed for the room you are in. BTW, make sure the mixer channel you have run the pink noise into has it's channel strip set to flat, and also your EQ needs to be st to flat. Use the parametric mids on the mixer to fight feedback issues of a given mic. Try to use as little EQ on the main system as possible, it will sound more natural that way.

While this is no where near what using my SMAART live rig with my EASE SysTune software and $4k worth of mics, it is a very simple but better than nothing idea.

You can also use the RTA app to find feedback on a mic and use its channel strip parametric mid to dial it out. Good luck!

 

[Lindsay]

... While this is no where near what using my SMAART live rig with my EASE SysTune software and $4k worth of mics, it is a very simple but better than nothing idea...

Great post.

Another cost effective idea is the AudioTools iPad app by Studio Six Digital. You can add the SMAART spectrograph module for $50 and even buy a measurement mic matched to the iPad/iPhone or an interface for a regular measurement mic from their online store. You can get the whole setup for around $270.

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[Keithwah]

Great post.

Another cost effective idea is the AudioTools iPad app by Studio Six Digital. You can add the SMAART spectrograph module for $50 and even buy a measurement mic matched to the iPad/iPhone or an interface for a regular measurement mic from their online store. You can get the whole setup for around $270.

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That would be certainly be a much better method than what I had suggested. The AudioTools app is great and I use that when I'm doing my initial acoustical consultation to see if I even can re-tune the room or if there enough issues that need acoustical panelings. I have seen the SMAART app at the Infocomm show in Vegas this year and did like it and had thought about it, but didn't really need it. But for around $270, that is a seriously pro package. It does way more than the IVIE IE-45 I bought for $2.5K about 5 years back. But yes, great idea!

I use a pair of 24" flat panels to monitor the software for my tuning work and also the software for the Digital Signal Processing on the other. And I drive SMAART and my IVIE IE-45 from a separate laptop for various tests and second looks. I do however have a nifty PC snagging app called Splashtop, that I can take and walk the room with using the SMAART or IVIE software.

I'm running around with a set-up rig that is not easily in reach for guys that don't tune sound systems for a living. But I was hoping some guys would hip up to the idea that they don't have to have sound that completely sucks and that they are some useful, while not really that accurate but far more reliable than using your own "ears". And they can spend like squat on it.

 

[Zooberwerx]

I use the RTA / Auto EQ on our DriveRack. The unit displays the adjusted GEQ profile after the fact. I've found the response curves to remain fairly consistent room-to-room, venue-to-venue. This is pretty handy as sometimes auto EQing the room is not always practical.

Riis

 

[1958Bassman]

how i eq a system is to ring it out, stick a mic in the middle of your room (if you have an RTA mic then use it, in a pinch just use the most sensitive mic you have, not ideal but can work out well) then from there just pull out the frequencies that are giving you the problems.

then i will generally play track through (with the EQ on the board flat) it to see what the PA sounds like. even then i will do most of my eq'ing on the console rather than touching the 31 band. whats the point in adjusting what you have adjusted.

i sometimes (most) will use my iphone app (JL AUDIO and its free) to help me pick frequencies i can't find. even though most people will say not to use an iphone for this and for the most part i agree, i find this a most helpful guide.

I have the same iPhone app- do you find that the RTA shows the response skewed toward bass-heavy? Did you calibrate yours?

 

[slap-a-da-bass]

I've been working with my system all week. I'm using the guitar players Behringer RTA/eq unit, and for now, and I'm working in our practice space. The RTA, auto eq runs fairly quick, maybe just a minute or two, after that, there is minimal change in the eq. My observations; After the EQ is set to the RTA adjustments, I find some of the mud that was present is gone, but to my ear there is too much top end, almost getting harsh at higher volumes, and even though the mud is gone, it sounds slightly thin to me. Looking at the EQ curve, there are bands right next to each other that very by 20db, which means eq adjustments that are +/- 10db. I felt it was drastic. I changed the max span on the auto EQ to 12db, with a max +/- to 4db. The curve is smoother, and to me sounds better, even though the RTA would want to move the eq sliders more.

Any idea why the auto eq, would have large changes in freqs?

Also, I'm making judgement on tone based on recordings that I know. Maybe live it will not sound right? As I said in the beginning, many local bands sound dark & muddy to me.

 

[Big_Daws]

I have the same iPhone app- do you find that the RTA shows the response skewed toward bass-heavy? Did you calibrate yours?

actually i find the opposite...i find that the roll off on the top and bottom end too sudden. but that i guess is probably the characteristic on the iphone mic, so i take that into consideration. so what i do really first is play an extremely well produced and clear audio track that i know really well, see if i notice any glaring peaks, if not i then grab out the mic, ring out the room find he feedback peaks and then i play back the track and see how it sounds flat. but very rarely do i ever completely pull any frequency right out. and yes...i did calibrate mine to reflect a little more accurately volume levels and that seemed to help a lot...

 

[Lindsay]

And I drive SMAART and my IVIE IE-45 from a separate laptop for various tests and second looks. I do however have a nifty PC snagging app called Splashtop, that I can take and walk the room with using the SMAART or IVIE software.

I'm just feeling my way in this area but it interests me and I'm keen to learn more.

I understand how to correct the frequency response of a set of speakers. I understand how tune a system from a single location i.e. the middle of the dance floor. I understand the different frequency responses I get in a room when I move the measurement mic around.

What I don't understand is what to do about those different frequency responses (assuming the subs are clustered, the mains are well positioned or you've exhausted the venue owner's tolerance for alternative speaker placement).

What kinds of adjustments do you make on the basis of the information you gather from the system mentioned above? For example, the seat-to-seat function in the IE-45.

 

[Lindsay]

I've been working with my system all week. I'm using the guitar players Behringer RTA/eq unit, and for now, and I'm working in our practice space. The RTA, auto eq runs fairly quick, maybe just a minute or two, after that, there is minimal change in the eq. My observations; After the EQ is set to the RTA adjustments, I find some of the mud that was present is gone, but to my ear there is too much top end, almost getting harsh at higher volumes, and even though the mud is gone, it sounds slightly thin to me. Looking at the EQ curve, there are bands right next to each other that very by 20db, which means eq adjustments that are +/- 10db. I felt it was drastic. I changed the max span on the auto EQ to 12db, with a max +/- to 4db. The curve is smoother, and to me sounds better, even though the RTA would want to move the eq sliders more.

Any idea why the auto eq, would have large changes in freqs?

Also, I'm making judgement on tone based on recordings that I know. Maybe live it will not sound right? As I said in the beginning, many local bands sound dark & muddy to me.

In my experience, big cuts/boosts in adjacent bands are usually around the crossover frequency. If this is the case, it is better to smooth the response from the crossover first, then tidy it up using the auto EQ.

Regarding your harsh highs - there is nothing stopping you from further adjusting the EQ to taste. Try playing a good quality recording of a song you know well through the system. The song you choose should represent the whole frequency spectrum relatively evenly.

This area gets subjective - try very gentle adjustments and remember (write down) the original settings. Just last week I looked on as a DJ completely destroyed a system I had just tuned.