RTA Etc,

[SamG269]

Today I went to one of my sisters church. Very small church. Two JBL speakers hanging on the front wall for FOH. I turned to her and asked right when we got in... "Let me guess, you guys have horrible feedback issues?" And she said "Yes all the time.'

The funny thing was they did have an eq unit for the mains(with a grill on it and everything). But I like I told my sister, it doesnt matter if there is an eq they'll never be able to eq that to the point of no feedback from the mics that are right in front of them.

She told me to tell the pastor and I declined. Why you ask? Well...

1. I dont know how to offer help in a way that will be recieved by someone who might think his members are already doing a great job. Or if he ends up being to stubborn to say "yes we need help".

2. I dont know how to fix the problem. Hence I would like to learn how to use an RTA to fix issues like eq'ing the room.

Oh. And they are using wireless mics to mic the drum.... Why? I dont know. They feed them into a small Behringer mixer and then Im guessing that goes to their Mackie Mixer in the back. .... Anyways.

If I can have some suggestions as to how to come to the pastor with this. And also what would be needed to get an RTA and use it. I know there are multiple mic RTA's but I dont know how hard that would be to use. I would love to have one and know how to use it. But like my sisters church for example. Small set up. I wouldnt necesarily need a multi mic RTA would I? With a simple one I should be able to eq the room correctly.

Sorry for the long post. I hope I make sense.

[tdangelo]

For RTA you can get pretty good results without spending a lot. I use two apps on Android (running on a Motorola Xoom tablet, but they also work fine on my htc Evo phone).

They are "Speedy Spectrum" and "Audio Tool." I think my total investment was $3 ea. I am sure there are plenty available for iPhone/iPad.

Back in the day a dedicated RTA would cost me $4500-6000 USD plus >$1000 for a calibrated mic.

Interestingly enough I ran sweeps in our ProTools room comparing the Xoom internal mic to actual and above 80-100Hz the Xoom was right on the money.

Technology ... you gotta love it!

[Tim Padrick]

Anything you would use needs IMHO to have at least 1/12 octave resolution, though 1/24 would be better. FFT for iPhone and iPod are very good, and only $25. There's a measurement mic available if you want to get fancy.

[waynehoskins]

I have the Audiotools suite for the iPhone, and it's excellent. $20 for the whole basic suite, but it has RTA, SPL meter, delayfinder, generator, and more, and there are advanced modules you can buy if you need them. It's pretty good, and it's always with me.

Next step for me would be Smaart, for "real" measurements -- but I imagine for most things the phone is close enough. I just used my phone tonight to flatten out my nearfield monitors for a show and measure approximate coverage in the room.

[Brad Weber]

You are very correct that an equalizer is greatly a 'band aid' in such applications rather than a solution.

An RTA can be useful, however it is also rather limited in what it can do. I still use an RTA to record noise levels but I no longer use one for system tuning. If you have a one-third octave equalizer and a one-third octave RTA then it may help show in what band feedback is occurring but that is about the extent of what it can do. I will typically use a more discrete frequency FFT analysis or more often a two channel system like Smaart and SysTune along with simply listening.

Keep in mind that system tuning or voicing can go well beyond equalization. For example, what a slight change in how or where the speakers are mounted or aimed provide better results than extensive equalization?

My approach in similar situation has been to try to turn things around and rather than lecturing them, try to get them to 'teach' me. You might possibly soften a discussion on the wireless mics if you said something like that you have not seen anyone else do that and could they help you learn by explaining why and how they do it? Sometimes you get surprised and actually do learn something but even if that is not the case it can be a way to open a dialog about it.

[Tim Padrick]

@ Wayne: If that's the Studio Six Digital tools that you have, you should check out FFT (unless you are indeed going to get Smaart).

[SamG269]

Thanks for the responses guys. So how tech savvy does one need to be to use one? Say for instince, say I buy an app for my iphone. U just open the app. Place the phone in different locations in the sanctuary and apply boost's and cuts to the frequencies that are not flat? And for multi mic setups for bigger venues, whats available? And are they more difficult?

Originally Posted by Brad Weber

My approach in similar situation has been to try to turn things around and rather than lecturing them, try to get them to 'teach' me. You might possibly soften a discussion on the wireless mics if you said something like that you have not seen anyone else do that and could they help you learn by explaining why and how they do it? Sometimes you get surprised and actually do learn something but even if that is not the case it can be a way to open a dialog about it.

Thanks for the tip. Never thought about "confronting" that way. Ill have to use that in a lot more situations now. lol.

You also mentioned that maybe its not so much the eq of the system in particular but placement of the speakers. In this situation its obvious that the problem is that the pastor literally stands in front of the speakers. But the problem is that they are 3 way JBL's. The big 5 foot ones. So flying them would not be possible. If they did ask me for help I'd tell them to seel the ones they have and buy flyable speakers with a sub. Small space. Small sub.

[Brad Weber]

Originally Posted by SamG269

Thanks for the tip. Never thought about "confronting" that way. Ill have to use that in a lot more situations now.

It can actually be very enlightening to watch people try to explain why they do something the way they do. Sometimes it turns out there is some very good reason that they have developed some approach for that specific application and you learn something. Sometimes they have no idea of why they do it or it turns out they are operating based on rather egregious misunderstandings. But the most fun is when someone starts to explain it and you watch the realization dawn on them as they go along that they never really thought about it and that there isn't any specific reason for what they do other than that it is they way they've always done it or were told to do it. That sometimes get them to start thinking about things and even expanding that to other aspects of the systems and its operation. And to me just giving give the answers or offering an opinion on how to do something is not nearly as effective as getting someone to start thinking about why they do things the way they do and looking for potential improvements on their own.

That's also the idea behind SynAudCon which has always been based on the concept that if two people meet and exchange dollars then each walks away with a dollar and has gained nothing while if two people meet meet and exchange ideas then each walks away with two ideas and both benefit from the exchange.

[SamG269]

So where do I look for the apps? I like the $3 dollar one.... haha.

[Tim Padrick]

Originally Posted by SamG269

So where do I look for the apps? I like the $3 dollar one.... haha.

If the app is for Apple hardware, your only choice is the Apple app store (unless your device is jailbroken).

[TimothyPaul]

I would first approach the Pastor with a positive approach. In general, if you tell people they are doing something wrong, they will get defensive.

It would much better to tell him. "Wow, you have an awesome PA system, the presentation during service really helps move me to the Lord. If you want I have some tools and knowledge that may help tweak the system so you can get more out of it."

Then take some good trust worthy well recorded CD's (not MP3's) and listen to them on a known good system (Steely Dan - Aja for example) and learn what they sound like. Then take them into the facility and compare the sound.

When we EQ to RTA, there are two problems. One, because of live sound, we often end up EQ'ing for feedback versus sound quality. Second, we have often get caught up in theory and lose site of reality. - Balance everything out.

One of the most critical things I do, is make sure I leave a fallback. For example, if you are going to EQ the Pastor's mic, make sure you remember (take a picture of the EQ on the board with your Iphone) so you can revert back to you old settings if something goes wrong. I am currently re EQ'ing a sub woofer setup, so I brought in an another EQ. I am leaving the old one in place so worse case scenario, I just plug the outputs from the PA back into the old EQ.

I use the Iphone apps mentioned earlier and they are great but you can also use some of those old Rane devices. They are cheap nowadays, work great and you can leave them in the rack. RA 27's work great.

Again, make sure you have a point of reference. If you use an Iphone app, take a snapshot of the reference CD sound in that good facility to compare.

Lots more thoughts for you - I check back later.

TP