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Monolithent
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And to answer your question about what to adjust in the event of feedback.
Adjust the EQ for the Monitor itself. If the freq is out of line and you tweak the monitor, the only one who knows is the artist behind it and not the paying audience.

I run my monitors off the aux outputs. They go from the aux TRS connection to a 31 band mono EQ to the monitor. That way I still have the 4 band on the SL for shaping the sound after I ring out if necessary. Just be careful with it. Once you have each monitor rung out only lower volumes on that channel. Never boost. Again...gain before feedback.

As far as a recommendation for a 31 band. Pretty much any pro grade unit will work fine. I'm actually, based on recent personal success with it, putting Samson D-3500 parametrics in that part of the signal chain in place of the Graphic EQs. Due to low cost good performance in my opinion and 15 fully parametric notches per channel. That and the SL should be plenty for nearly any monitor application. If you have deep pockets the DriveRacks are better now than the first editions and have a ton of processing capability. Ashly Protea series are excellent as well. Depends on needs and budget. I have a first edition Driverack PA on my Mains with a D-3500 in stereo before it and my system has a beautiful sound.
http://support.presonus.com

Tallest guy in the Mod Squad with all his hair still on his head.

No I'm not a freaking pilot!! The Air Force won't let me have a suit with a zipper...or sometimes shoestrings.

My advice and suggestions should never be considered advice or suggestions. These are mostly insane ramblings of a poor aircraft mechanic who can, strangely enough, still hear.

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kibo
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Joined: 28/07/2010 23:08:13
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hi guys,

i asked the question because my church bought a new PA system. inspite of me telling them not to buy the stuff that thtey bought they still pushed thru. the system goes like this:

Allen and Heath mixwizard 16
Behringer FBQ 3102 Eq with feedback suppressor
Yorkville AP1020 amps
Yorkville CC2285 i think...

we were cutting almost all of the mid and high frequency just to get rid of the feedback. we use a gooseneck condenser mic for the pulpit. we couldnt get enough volume out of it. its so bad a system! we could get by using the sm 58s though. it didnt have a lot of problems.

we were using EV FR12 before with EV amps. i suggested to them not to buy if it wouldnt be better than what we had. but they pushed thru. its hard if you talk to church leaders who doesnt also understand anything about what they are doing with regards to sound. and they tend to be cheap on this area.

we had a major renovation at church and all they wanted was just to buy new stuff even if the old ones are better.

anyway, just sharing my heart out with my frustration. we the praise team are living the consequence of their decision. this is partly why i bought all my stuff for us to use for special activities.

anyway, we had a lot of headroom when we used the EV stuff. it had only 15 band EV eq if im not mistaken. but it sounded better with the same mics.

i dont expect you guys to try to solve it for me but i would love to get some advice. that is also why i want to learn how to use these spectrum analyzers..

thanks,

kibo

This message was edited 1 time. Last update was at 02/08/2010 07:34:12

Studiolive 1642, Tube Pre, QSC K12s, Imac 21.5 8GB 3.06 Ghz, MacbookPro 13" i5, Blue Spark Condenser Mic
Monolithent
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Just by looking at it you've got a very good board. I am assuming a single 31 band EQ on the mains. Good amps and speakers. A condenser mic and a praise band.

First off get the system sounding good to the one most critical ear in the place first with the mics off. Play some gospel music through it and make it sound as good as you can with the board and available equipment.

Then fire up your mics and bring the levels up slowly till they start to howl at a low level from feedback. Try to keep them howling and find the freq on the EQ and lower it till it stops then raise the mic level again and repeat until you're at a comfortable mic level. You can use the EQ on the A&H but I would recommend it only as a last resort to eliminate feedback.

Some other things to consider. The phase of your system. Get something to check it. Speakers out of phase with each other and other pieces of equipment can cause feedback problems. The location and aiming of speakers (even ones in guitar amp cabs if they're miked) in reference to open mics can induce problems. System noise floor can also cause problems. If there is a 60hz hum in your system it can get into your mics and generate feedback on that freq. A low set gate or downward expander on your open mics can help out substantially.

You can do a lot just by adjusting where things are located and aimed. Think about the levels your band is running on their gear. Think about where the pulpit is in relation to the mains. Can you move it around? Does the bass player need to have a full cab onstage or can you just run him through a DI to the board. Where does the lead guitar have his amp sitting? Is it flat on the ground, is he sitting on it, is it hitting his butt or his ears? Get those things aimed where they need to be...in the ears of those who need to hear them...it will get the stage volume lower and less noise onstage is less chance for feedback.

Studying the Systune stuff now. Should have something for you shortly. We definitely need to get that system leveled out or you will be fighting feedback all the time.

This message was edited 1 time. Last update was at 01/08/2010 21:45:28

http://support.presonus.com

Tallest guy in the Mod Squad with all his hair still on his head.

No I'm not a freaking pilot!! The Air Force won't let me have a suit with a zipper...or sometimes shoestrings.

My advice and suggestions should never be considered advice or suggestions. These are mostly insane ramblings of a poor aircraft mechanic who can, strangely enough, still hear.

StudioLive 16.4.2, AudioBox 1818VSL, AudioBox 44VSL, Faderport, Digimax FS,, M-Audio Firewire 410
--MultiBoot System--
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kibo
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lowtech,

eversince we had the new stuff on we havent used for the band yet. even with the old system when the praise band play we only use it for the vocals.

have you ever tried to be very frustrated in what your doing? we tried the whole day and nothing seems to work. maybe the placement of the speakers is one thing and all our space too has no good acoustics. echo everywhere. i suggested to them to buy parametric eq instead of the ordinary 31 band.

when we tried it, it was just the pulpit mic. no band and it was so difficult. we tried sm58s and it was a bit better but still not acceptable.

thanks so much for taking time to help me out here.

im planning to buy the driverack px coz the mic is included anyway then i believe there is a parametric thing on that. (im buying these stuff to tune my system and at the same time to tune the churchs')

thanks again,

kibo

This message was edited 1 time. Last update was at 01/08/2010 22:42:40

Studiolive 1642, Tube Pre, QSC K12s, Imac 21.5 8GB 3.06 Ghz, MacbookPro 13" i5, Blue Spark Condenser Mic
Monolithent
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Just shot you a PM. It should help. Systune is very similar to Smaart with the only differences I see being from add-ons in one or the other.

I read through a single line setup somewhere around page 19 of the manual its more of an RTA as opposed to how you'd do an FFT. I'm still reading, but the first PM should get you started and we can add on as necessary.

This message was edited 1 time. Last update was at 02/08/2010 19:03:10

http://support.presonus.com

Tallest guy in the Mod Squad with all his hair still on his head.

No I'm not a freaking pilot!! The Air Force won't let me have a suit with a zipper...or sometimes shoestrings.

My advice and suggestions should never be considered advice or suggestions. These are mostly insane ramblings of a poor aircraft mechanic who can, strangely enough, still hear.

StudioLive 16.4.2, AudioBox 1818VSL, AudioBox 44VSL, Faderport, Digimax FS,, M-Audio Firewire 410
--MultiBoot System--
Win Vista 64/XP Pro/7 x86/7 x64 - Mac OSX Snow Leopard/Lion
Gigabyte motherboard--SYBA TI Firewire XIO2200A--i7 2600k Quad Core--16 GB DDR III--Custom 2U Rackmount--4 TB Raid (all internal SATA II)--19" Samsung HDMI LCD on pivoting VESA 1U Mount
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Jerryd
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Joined: 28/07/2010 16:01:24
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Kibo -- Systune should be fine. All Dual FFT analyzers basically do the same thing -- which is measuring the frequency response of your system. So, I think you will be fine. I was introduced to Smaart and that it the only program I know. Maybe I will download systune and fool with it just to see how it compares to SMAART but if you got the program for free -- then that is cool.

Don't get hung up in the best measurement mic. I have several DBX models & they are all fine so get what you can afford. In the mean time -- you can start evaluating your gear. For example: Go through ALL of your cables and make sure they are wired correctly. I use a polarity checker called a Galaxy Cricket BUT it costs money so you can use a cheap "Multi-Meter" ($10.00) and use it to confirm cables wired correctly. The standard for mic cables: PIN 1 = Shield, PIN 2 = HOT, PIN 3 = Cold. So find PIN 1 on both ends and check it to see if you get a connection and repeat for ever pin and every cable. It is going to take a while. Don't assume the factory got it right for you. I have a $2,000 mixer that came straight from the factory to me with the main output polarity INVERTED! So -- I know cables can be wrong.

What happens when you go thru this process is an eye opener AND you will really get to learn your system forwards and backwards. You will be able to diagnose on the fly pretty easily if something comes up.

Good job Kibo! Hey one more thing - With your K12's -- you may be better off going with something else other than the DR PX. The reason I say that is you are only going to have 3 parametrics available to you to smooth out your response. You will gain two more if you have subs. Three is OK BUT usually it will take a few more to get it within + or - 3dB. You still need a crossover though right? The PX doesn't have time alignment either. The DRPA does (10ms). What would do an incredible job would be the DR 260. You would have 9 Pre XO parametrics available and 4 Post XO. That is 13 if you use the full range tops. You get four more for your subs if needed and if you had bi-amped tops -- you gain another 4. The DR 260 has a brick wall limiter the other two DR's do not. The tool set in the 260 is so far beyond the PA and the PX. BUT again, it costs more. I know the PX come with a measurement mic in a package deal so I know that is appealing. The 260 doesn't cost much more than the PA+ and is waay better. I know where you can get a 260 for under $700 brand new. it comes with the GUI software and you can actually run it on your laptop as well.

This message was edited 1 time. Last update was at 04/08/2010 03:54:51

kibo
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hi jerryd,

about the polarity of the cables, i have a behringer cable tester? would that be ok to test the polarity? i have a digital multitester too. i made most of my cables and just tested them with the cable tester.


so if im working with the churchs' amp, i would have to trust that the speaker polarity is ok right? if not, how will i test it with a multitester? just simply reading a positive value and figure the red and black leads? i know with the k12s i dont have to do that right? can you tell me how your phase tester works if you dont mind?

just curious why i need to have a crossover with my k12s? if i use one of the Ksubs or kwsubs in the future would i still need time delay? maybe it depends where i place my subs right?

i havent read much about the DR260 but i think it is very nice! does it come with an RTA? im thinking now that in the long run DR260 will be very useful if i want to grow my system. i have to do a lot of explaining to my wife.... hahaha! hard to justify these things. ive just started this march doing this stuff and it has been fast with the SL and K12s.

im in toronto and prices there in the US are better. anyway, i will PM you about the DR260.

thanks a lot again for your help. really appreciate it!

kibo

This message was edited 1 time. Last update was at 03/08/2010 02:29:09

Studiolive 1642, Tube Pre, QSC K12s, Imac 21.5 8GB 3.06 Ghz, MacbookPro 13" i5, Blue Spark Condenser Mic
agn
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Joined: 03/08/2010 16:51:32
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A cheap RTA mic is just that, and will not give you the accuracy you need. Don't waste your money on a cheap mic.

AFA Sound system setup for dummies, Smaart and other programs have tutorials, and many local pro audio suppliers have classes on it. System analysis and tuning is a very specific duty. If it is not done correctly you can do some serious damage to your system.
Jerryd
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kibo wrote:hi jerryd,

about the polarity of the cables, i have a behringer cable tester? would that be ok to test the polarity? i have a digital multitester too. i made most of my cables and just tested them with the cable tester.


so if im working with the churchs' amp, i would have to trust that the speaker polarity is ok right? if not, how will i test it with a multitester? just simply reading a positive value and figure the red and black leads? i know with the k12s i dont have to do that right? can you tell me how your phase tester works if you dont mind?

just curious why i need to have a crossover with my k12s? if i use one of the Ksubs or kwsubs in the future would i still need time delay? maybe it depends where i place my subs right?

i havent read much about the DR260 but i think it is very nice! does it come with an RTA? im thinking now that in the long run DR260 will be very useful if i want to grow my system. i have to do a lot of explaining to my wife.... hahaha! hard to justify these things. ive just started this march doing this stuff and it has been fast with the SL and K12s.
kibo


Hey Kibo, That would work fine. If the continuity of the cable is good (+2 lights up green & when switch is moved to pin 3 mode -- you get a RED light), then the polarity will be good. Follow the instructions manual with your tester to make sure you know what it all means. I am sure you already do. Do the check with EVERY XLR cable you have.

About the Church Polarity thing: No not really. The fact that it is in a church means you really should check it. There has probably been numerous novices tweaking with that system doing this and doing that....etc. Church systems are the worst & the current sound guy may not like anyone messing with it. (sounds like all sound guys)

Like I said before -- you would THINK coming from a reputable company that everything would be in check right? If I had the K12's and the KSub -- I would be all over them searching for possible issues. Why? Because the stuff most likely wasn't assembled here in the US (Like that would make a difference) BUT my point is -- There are so many places where the polarity can get inverted that you want to have a system that functions the way it is supposed to. When the drummer stomps his kick drum -- there needs to be a POSITIVE OUTWARD motion of the speakers when it finally gets thru the signal path & then on out to your ears.

In Bob McCarthy's book on Sound system optimization there is a whole chapter dedicated to Examination & then another on Verification. He doesn't trust anything until he confirms it. So you are going to go thru the gear using your eyes for inspection, your tester for cable continuity, use your multi-tester for speaker cable testing. Use a 9 volt battery on your speaker leads to make sure the cone moves outward with a postive impulse on it. If you can't get into your K12's (Don't VOID the warranty) use a connected speaker cable to the k12 with one end where you can get a 9 volt on it and make sure the cone moves outward with a postive impulse. Don't ever use a 9 volt on a horn. It may torch it. Horns are a different discussion & that is where a polarity checker is handy.

Do a search on "The Cricket" by Galaxy Audio. They are about $100 and do all kinds of things. You have a send unit and a receive unit. One sends the signal into the system & the other one measures it. You can check microphones with it too and YES microphones can be wired backwards. Trust nothing when it comes to optimizing your system.

Do you need a crossover? Well with the K12's and the KSubs -- Nope. So if you wanted to get a stand alone parametric like LowTech was saying and he bought -- that may be the way to go. I didn't catch you had a KSub. If you had another brand of sub that was passive I would say YES.

Honestly -- you shouldn't have to do anything with the K setup BUT if you are like me - I would want to measure it with Smaart and see where I am at.

Your top boxes (K12's) are already aligned. If you place your top directly on top of your subs -- you probably won't have to align the top with the sub. If your subs are away from the top boxes -- then aligning them would be beneficial. It would sound cleaner because the mid woofer (top box) and the sub are hitting exactly in synch with each other.

The 260 is incredible in so many ways and would be a must have for me. I could take a 260 and my smaart setup & within two hours make anyone's system sound better than a system that hasn't been optimized.

Hang in there Kibo -- you are on the right track.
Jerryd
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agn wrote:A cheap RTA mic is just that, and will not give you the accuracy you need. Don't waste your money on a cheap mic.

AFA Sound system setup for dummies, Smaart and other programs have tutorials, and many local pro audio suppliers have classes on it. System analysis and tuning is a very specific duty. If it is not done correctly you can do some serious damage to your system.


Just how accurate is accurate agn? If we all had a couple of thousand dollars and all of the other top of the line gear then I might consider a pair of Earthworks SR 30's BUT it will NEVER be necessary for live sound applications here. The Audix TR-40($180) is the next step up from the $100 mics. Is that good enough?

Read this thread from the DBX Forum on measurement mics. Harry Brill, Jr. a Rational Acoustics instructor talks about it and he has been doing this EXTENSIVELY for the last 25 years. Here is what he has to say about $100 mics:

http://www.dbxpro.com/Forum/viewtopic.php?f=28&t=1894

AGN -- When you post -- PLEASE explain your reasoning. Don't throw out a "Oh Huh!" You seem to know a lot about sound & I am always eager to learn. When I say something on here that begins to make a member cringe -- I don't want them to feel bad or inferior or whatever........ and if they ask me "Dr. J, can you explain that to me better or can you give me an example or where did you get that information", I would be happy to do that.

I have read countless posts from you on the other forum and it is time for you to re-evaluate your approach.

A $100 measurement mic WILL get you closer than no measurement mic at all. That is really what we are trying to figure out here. What would be the next move in this crazy expensive world of audio gear and how can I make it sound better for less. It doesn't make sense to spend $800 on a mic when you can get a speaker management device like a DR 260 for $700 and a measurement mic for $100. You will have gained much more because you have more tools to work with.

The only way I can see a guy wrecking his system with Smaart is by running Pink Noise at full military power which doesn't need to be done. I suppose the gain structure needs to be set first as well BUT come on -- with a little encouragement and help -- most guys CAN get this down.

Your posts always have the "Oh Huh" in there and the doom and gloom factor. With all your knowledge -- try to be more of a teacher. There is a lot to this sound thing than just turning knobs and using your ears.

Can you do that?
kibo
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hi jerry,

If i buy the Cricket would it be just a one time use for me with regards to the system. once i check it and all is good and thats it? i believe it is not one of those device like the smaart that can see phase problems right? sorry just a newbie question.

ive been learning a lot in a few days than the months that ive been starting. it seems to be overwhelming but im very excited in learning new things. thanks to you and lowtech and of course the guys here in the forum.

i dont have subs yet. im just trying to take things at a time. like i said its hard to justify things that you buy for your hobby when you are married.

if you were to decide which things are more important? can you put it in sequence? tnx.

Subs, Driverack 260 w/ RTA mic, Cricket, Systune full version(do i really need it?)

thanks a lot!

kibo

This message was edited 1 time. Last update was at 03/08/2010 19:13:11

Studiolive 1642, Tube Pre, QSC K12s, Imac 21.5 8GB 3.06 Ghz, MacbookPro 13" i5, Blue Spark Condenser Mic
Jerryd
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Ok Kibo -- let's start over from the beginning so we can see what is the most important thing next in the line of gear. What ALL do you have?

To answer your question on the polarity checker: Yes it is kind of a one time thing BUT you will find yourself using it constantly. Cords need repaired quite often and when your under a time constraint -- will help you quickly.

I have two monitors up front and center that are daisy chained together. These are for the singer only. The other night at a gig the singer stepped in between the two monitors and ripped the speaker cable right out of the speakon connector. I had to re-wire the thing on one of their breaks and for the most part -- in the dark. I thought I had it right just by visually looking at it. Just to make sure -- I ran the Cricket thru the entire signal path all the way to the monitor getting a Positive impulse reading. I knew it was correct.

It is an invaluable tool for sure. SMAART can and does evaluate Phase. It is a bit complicated to explain it here but if you get to that point -- I can show you how to check that. The cricket can do all of it pretty easy.

I can check a system at a gig for polarity without the sound guy even knowing what I am up to. When you get better at this -- you can actually hear the phase issues in the system. It will have a weird alien type of sound & be distant instead of in your face.
kibo
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hi jerry,

i only have SL1624 and 2 QSC K12s.

6 sm 58's
1 senheisser vocal(im at work acnt remember)
1 Sennheiser e 602 II for kick
2 Sennheiser e 604 for snare and toms
1 pair behringer C-2 condenser mics for overheads
3 behringer DI
1 presonus tube pre DI for bass

cabinets at church are yorkvilles. small amps cant remember the models. we use yorkville monitor speakers at church (8inch with horn,passive) with EV 100watts amps i think, that we use to use for FOH at church.

im really trying to hold my impulse to buy all the stuff that i want... please let me know wchich one would be important.

by the way our church holds maybe 400-450 people.

thanks,

kibo




This message was edited 2 times. Last update was at 04/08/2010 04:36:53

Studiolive 1642, Tube Pre, QSC K12s, Imac 21.5 8GB 3.06 Ghz, MacbookPro 13" i5, Blue Spark Condenser Mic
Monolithent
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Hey Kibo,

For the phase tester, call around to some of the local system rental companies in your area. In Montreal there has to be at least one or two.
See if they will let you rent or borrow one for a couple days. That way you're not out a ton of money for someting you may not need again for a while.
http://support.presonus.com

Tallest guy in the Mod Squad with all his hair still on his head.

No I'm not a freaking pilot!! The Air Force won't let me have a suit with a zipper...or sometimes shoestrings.

My advice and suggestions should never be considered advice or suggestions. These are mostly insane ramblings of a poor aircraft mechanic who can, strangely enough, still hear.

StudioLive 16.4.2, AudioBox 1818VSL, AudioBox 44VSL, Faderport, Digimax FS,, M-Audio Firewire 410
--MultiBoot System--
Win Vista 64/XP Pro/7 x86/7 x64 - Mac OSX Snow Leopard/Lion
Gigabyte motherboard--SYBA TI Firewire XIO2200A--i7 2600k Quad Core--16 GB DDR III--Custom 2U Rackmount--4 TB Raid (all internal SATA II)--19" Samsung HDMI LCD on pivoting VESA 1U Mount
Studio One v1 Pro x64
Studio One v1 Artist
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kibo
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lowtech,

ok im going to try to do that. im in toronto.

let you know soon on wgats new!

kibo
Studiolive 1642, Tube Pre, QSC K12s, Imac 21.5 8GB 3.06 Ghz, MacbookPro 13" i5, Blue Spark Condenser Mic
 
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