Sound Advice - tips for fighting feedback in your live sound rig
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- Опубліковано 11 лип 2010
- a quick and easy visualization of what feedback is and how to get rid of it from your PA system. This is not an all-inclusive tutorial, but it will help you understand the basics of what to look for and how to troubleshoot your rig and improve your sound!
This video (was uploaded 10 years ago) has the best way to explain about feedback problems. I love the funny pictures and the hilarious way to teach the amateur like me! Thanks Jonas!
This is a fantastic tutorial. I used this to explain to someone how to fix their problems and they now get it perfectly. Thanks for creating this. VERY USEFUL.
Fantastic explanation, Jonas. Your tutorial was obviously intended for those of us who don't call ourselves "sound engineers". It is very helpful to me. Thank you!
Great presentation: very informative, concise, and yet pretty thorough! Thank you for taking the time to prepare this video. I didn't realize that the cardiod field expanded/condensed in direct proportion to the gain. Also, the tips to fighting feedback were insightful. I can't wait to implement the info at our church. Thanks a lot, Jonas!
SUPERB presentation - All meat, no fat - a GREAT roundup of core concepts!
(Bonus points for being so young and delivering such polish - that was a corporate board-room quality presentation)
Thanks!
Thanks dude. I'm using nylon string guitar,harmonizer,zoom A3 w feedback suppressor. I was aimims speakers at mic. This and the room created mega problems at practice. Now I know what to do..... THANX
I can tell you spent a lot of time putting this together. Very well done. Thanks!
Dude, great vid, even 9 years later. Apprently having good content, good sound quality and some jokes sparkled throughout goes a long way
Wow! There was more info packed into this vid than any other vid about this stuff that I have watched in the last 6 months! It was so clear that I didn't need to rewind to "get it."
Thank you, thank you, thank you! :)
Dude you helped me sooo much. Me and my band can practice a little more peacefully now. Thanks
I really like this video, thank you so much for the help! I do wish the feedback sound effect was turned down by half though!!
Thank you very much! This video was extremely helpful! I am a mobile dj for small bars, so naturally my speakers are close to my booth. I have been getting unwanted feedback from the mic and speakers and I didn't know what to do. This cleared up everything for me. I'm glad i don't have to go out and buy new mics or speakers now, or some gigantic mix board, just to fight feedback. THANK YOU THANK THANK YOU 1000 THANK YOUS!
Great Tutorial! Thank you Jonas!
Thank you so much! Excellent video! Now I have a better understanding of how to go about fighting feedback.
Nicely done. Made it simple so I could understand it.
You sound so young like you could be 17 and you have the best video on the topic lol thanks a lot !
I am so happy that you cleared up my confusion about: unpleasant or pleasant. ;)
I thank you very much it is so help full .not only for me but also for all our staffs .
Daniel from Ethiopian national theater.
Very nice presentation. I've never really had feedback issues. I mute unused mics and cut the lows on the vocals. I love the panic as someone drops ALL the faders on the desk when they hear feedback though.
Good!! Thank's, this is a nice tutorial with pro knowledge.
Thanks for taking the time to explain through your presentation. I found it extremely helpful. :)
I looked and didn't see anymore vids from you like this one. I'm shocked! You are a fantastic instructor! You should really make more, more, more! Please:)
Your info is very good. Too bad so many people complain instead of appreciate what your offering. I for one appreciate you posting this.
Cheers
Nice video, the first half was very helpful to what I was looking for.
That's great info! Most hardware EQ's have a fairly wide Q (width), and they do effect more than just the fundamental 4 notes... sometimes dramatically so. Thanks!
Jonas
Excellent really useful. Cheers from Bonnie Scotland.
Very good explanation. Thank you
Wow, thanks! I thought he was poorly cast as Spiderman, but I appreciate the compliment! I'm glad you benefitted from the video. Good luck and God bless!
Well presented ! Like the animation.
It's my pleasure... you're quite welcome. I'm glad it helped!
Jonas
Hey Jonas. Great video man! I loved how simple and informative you made it. Thanks for sharing your knowledge hear dude. :)
Lol, can this guy make all the videos about live sound on UA-cam please, like give him a monopoly on it, he deserves it for this superb video, I learned a great deal and I've been gigging in tight spaces all my life, always battled with feedback even now after like 15 years of doing it. The video taught me a lot and I'm going to try theses things at my next gig. Because tonight I had this massive runaway rumble during one of the songs , I'm not sure weather is was the microphone or the guitar but it was so bad a actually had to stop the song and turn the mixer down, luckily it was towards the end of the song and I pretty much got away with it with a sympathetic o you fu×ed it up clap, lol.
O ye, I forgot to say, I was standing right at the back of the room as well with my back against the wall, that didn't occur to me something I learnedin your video, because I'm an idiot, who can't be arsed practicing with his full pa at home, but i should realy, but you cant make nosie as my house, so have to learn on the job, which in this instance isn't a very good place to learn because you're under pressure 😀
Thanks a lot for sharing the invaluable information.
Great informative video! Thank you
Great video.
This is one of the best video i have ever seen in my life. You d bomb!
"Feedback, It's very unpleasant" - Yes, it is! Thank you for demonstrating that! My neighbours really appreciate it. You could present the example at lower volume; a warning, perhaps!? I'm surprised you weren't more judicious considering the work you put in. A good video all the same
Nice video. Thanks for the info!
thanks a lot.... I've actually got a couple cued up and haven't gotten around to narrating and uploading them yet. I'm out of school for the summer, and they're now on my "to-do" list. Thanks again!
jonas
Very helpful thanks!
Great video man! Very helpful and visual.
wow, i actually learned something... very good presentation!
This was really helpful :)
very nice understanding video!
well explained, thank you
Great explanation...Thanks
thank you, my church will definitely benefit from the gained knowledge.
There is no mention, but I think a short delay will works also. By using the short delay is synonymous with extending the distance between the microphone and the monitor speaker.
You really should never do that
A nice clear video, thanks Jonas. I am retired and as a former pro guitarist thyis business was always done for us so in effect apart from one or two things its fresh info. Well Done.
Phil Cose but you always run into total idiots getting paid in beer...
@Jonas Anderson You did fine with your computer mic. You just didn't have to play the feedback sample so loud to make a point.
Great stuff!
great video.
Thanks for this video. But can you make one video in the actual of removing feedback? please... thanks in advance.
Just as important, if not more so to reducing feedback is mic technique. Keeping the mic very close to the source allows you to keep the input gain down which will reduce the chance of getting feedback. I had a retirement home client that was experiencing feedback in their dining hall. It didn't help that the speakers were in the ceiling. I trained the staff to hold the cardioid mic level with the ground and almost touching their mouth. I turned the gain down on the mixer and the problem disappeared.
Thank you for your help.
Fundamental knowledge is always really appreciated.
Could we also have the power-point file to scan it through?
thank you for the info.
Thank you for this!!!!
FYI: most analog 1/3 octave EQs have octave-wide filters centered every 1/3 octave. So, you're not cutting or boosting only 4 notes, you're cutting/boosting up to 12 notes. If you cut a graphic at 1k, it will affect down to 500 Hz and up to 2k. Some digital EQs allow you to set how wide the filter is, but most start with a default of an octave wide. Depends on the hardware/software.
Thanks, good tutorial. Last week I experimented with my Bose S1 Pro which I use with a Shure SM58. I found that IF I TURNED THE BASS WAY UP, THE FEEDBACK GOT SIGNIFICANTLY WORSE. Most people on stage only have access to Treble, Mid and Bass; (the S1 Pro only has bass and treble) so I guess they have to fiddle around and find out which frequencies are making feedback worse.
thank you, man! It was of great help for me :]
Good, vid. A simple math method to spot the most likely feedback freqs: divide the speed of sound by the distance between the mic and the nearest monitor. Most often, in a open space, it's around 1.8khz.
1.8 kHz would indicate a very short distance according to your formula, about 0.6 feet (speed of sound is 1100 feet per second, divided by 0.6 feet gives 1800 Hz). I'm just trying to understand how the formula works. A monitor that is 10 feet away would resonate at 110 Hz (1100/10 = 110)? But in an open space, the distance is somehow shorter (less than one foot)? I wasn't able to find this formula elsewhere. Thanks.
Nicely done! Your explanation was simple yet effective, especially for a neophyte like me. Thanks. BTW - I thought it was Tobey Maguire speaking.
I love my gates and compressors- especially with mics on instruments.
Hey Mahcsm, in my experience, once you find the feedback, using a sweepable EQ from your board (if it has one) or an outboard EQ is the most effective way of getting rid of it. The XTI's are wonderful amps, but real-time feedback isn't really one of their strong points. I hope this helps! Jonas
1. Pre-amp gain does not change the "size" of the polar pattern. This is a common mis- representation.
2. GEQ is for tone shaping. PEQ is for "surgical" adjustments.
3. FBX units are not a cure-all and when you understand how they work you won't need them.
4. Never, NEVER use compression in monitors.
The best way to decrease the chance of feedback is to use learn how to position, aim and process your PA speaker system. Anything else will be in the realm of surgical dressing for what should have been preventable wounds.
Thanx......this is very usefull for me.....
thanks good job
Here's some feedback you can't fight:
Thanks for the video!
for some musicians to put there mike stand at a distance maybe 80 cm or 120cm would be much better than put it on the wedge try to show them the gain in term of quality,for me it`is more a question of EGO than earing,try also toput only one wedge with 2 12" bass speakers it`2 times more efficient than 2 wedges where is really a hasard if you find the right angle and distance.and if you do that don`forget that our brain listen sounds after our left ear,wich means you have to work in stereo and put a delay(sorry it`s something like 3 or 5 milliseconds ,i don`T remember.........iknow when you are the leader of a band you think you are riddicoulus wiith nonly one wedge.explain to the other musicians thath`s better for every body excpt if they play on differrent placres on stage.And the last thing ask to the keyboard player if he absolutely need to have 2 di boxes to send the same sound on lft and right! GOOD NEXT SHOWS!
You already mentioned it's not an all-inclusive tutorial, but I think people who are watching this can be helped a lot with a practical approach. So I have decided to give this a try - at least in the way I should do it. Please comment!
In the right order:
1. When you set up the sound system in a new room with unknown acoustics, first "beep out" the feedback frequencies. Put a reference microphone on a stand on the stage, and crank it up carefully over the PA until you can hear some feedback. Search the frequency and suppress it. Now push it further and you will probably notice another frequency will give you feedback. Repeat until you're done. (B.tw. the reference mic is not some fancy microphone, just use one you need for vocals and put it on the spot they're going to use it)
2. Do the same with EQ-ing your monitors.
3. Let (for example) a vocalist sing and try to figure out at what main frequency his or her voice acts. When you have a parametric EQ: boost the mid heavily and go sweeping until you hear where the most amplification is. Compare the voice with and without amplifying it to give it a natural sound. You might turn the gain a bit down now - don't exegerate.
Now, take the rest out. It will prevent "bleeding" and thus feedback. Bleeding happens when a microphone picks up sound from other sources which are in the direct vicinity. You can not prevent it, but you can reduce it - also by good placing of the mics to other sources and eventually shifting the phase.
Be careful though not to take too much out, because you will end up listening to a singer singing in a tin can....
Of course you can do this with everything you mic, not just vocals.
That's about it for now :). Have a good gig!
Next time, please raise the volume of your voice. I turned up the volume to hear you better, then BAM feedback effect.
Tanner Hoke That's *exactly* what I just did.
along with everyone else. I think he's just a live sound engineer and not an audio engineer.
You sound like an audience member after feedback.
Or not play yet feedback
My philosophy is the same as yours... I shoot for 0 db on the LED's and go from there. It is OK for the meters to jump past that - in the sense that if it spikes once or twice, it's unlikely to cause any permanent damage to your gear. I still try to avoid it, better safe than sorry. Live sound is an unpredictable field, it helps to know the rules and then be ready to break them if the situation calls for it (especially with human vocalists... the most unpredictable!). Hope this helps!
Jonas you're very good at replying to comments , I used to habe a friend called Jonas , he was a nice guy. Also my cousins surname is Anderson, my uncle tels me it is of Swedish origin. So ye, love your name too, was Jonas I'm the bible or something, lol, don't get me started on that, I've been listening to the audio book version, did like 3 books, got bored. 😅
Excellent video man, very informative.
Just as a side note, compressors don't make quiet sounds loud, they only do that in the sense that you are using makeup gain. And after you have set the levels of the compressor, I don't think you would ring out a room with your band still playing.
Compressors can be troublesome with feedback, but more than likely would be when you have to go back to it and adjust the settings after you have rung out the room.
Still though, great video.
Thank you.
Great video! Can you explain how each slider is 4 notes on a piano? An 88 key piano starts at roughly 26 Hz and goes up to 4.2 KHz. So to EQ a piano with a 31 band EQ would you only use 25 Hz up to 4KHz? This would give you 23 (or 22) bands you could use for the piano. 88 divide by 22 = 4. Thank you!
I agree. It's the least effective thing a person can do... like turning the car off after accidentally grinding the gears. Muting the unused mics is a great way to reduce the overall noise floor, and most vocalists don't have voices that go down to 80-100hz, so dropping the lows is another great way to manage your live mics. thanks for watching!
Thank you
Thank you lol I have a small jam room in my basement and I could never hear the vocals because if I turned them up bam feedback! I turned down the eq and like magic it worked! see I'm not a sound man lol
HT MainSwitch well, that, combined with a bad room (short ceiling, small room...)...:) at my house, tall ceilings are in my favor
the video was done with the built in mic on my computer. those mics are typically not known for high fidelity :) I hope it didn't take too much away from the content of the information.
thanks it helped understand alot but my problrm is not while speaking its as soon as i turn the pa system on or the channels for my condenser mics, we used it before not a problem now bigger room and diffrent cables and as soon as i turn it on its an instant loud mid tone the gain has to be turned way low but then i run into very little pick up any sugestions..
Mate, if I'm looking for a video about how to correct feedback, I probably know what it is, good video though, thanks for your efforts!
I'm sorry about my first sarcastic comment, your video is actually very informative, and you clearly have a good insight into how live sound works. 👍
This is the best video I've seen for ages. Wel done man, you did a belter of a video.
there are a couple of in-line things called "feedback eliminators" made by Behringer or Sabine. I would recommend trying one and see if it works for your situation. I haven't used any feedback busting software yet. In a single mic situation, spend a little time with a feedback eliminator. Also, don't discount mic placement (closer to the mouth or throat) and speaker placement (try to point them away or at an angle). You might also want to check out the mic pattern. I have a mic vid that may help
thank you.
are the speakers movable?
I think one main thing he missed, is very important in basic PA setup, is speaker placement. and I see people mess this up all the time.
there should be a shear line, where the speakers fire away into the crowd, and the microphone should never be in front of them. People want to stick the speakers at the back of the stage for aesthetics, but they wind up firing direct into the mic. make sure your mic doesn't pass the invisible line directly between the speakers.
Wireless mics give you fits. A performer does a hair flip and the wireless mic is 2" from the monitor followed by a high pitched feedback squeal. A performer runs around the stage with a wireless then goes out into the audience in front of the FOH speakers and you get squeal. The sound person gets the blame but in truth it was caused by the performer. You set a gate in the mic and the performer gets mad because they can't scream into the PA. The performer decided to whisper and nothing comes out because the noise gate is closed. Lol. You can teach all you want but the real learning comes with experience.
It’s not the mic doing it for me. Trying to find out why I’m getting feed back. The mike doesn’t give me feed back. I wonder if the speakers is to close together. I’m getting it when my PC goes into the mixer only. And only at high volumes
i like how your name and your intro would be like "my name is jonas" from weezer
thanks!
thaks and good done video
I loved the video, but what is it that you did exactly to help you with the feedback. I am in the same boat... I do everything I can with Speaker Placement and I love my setup,, would hate to add unnecessary equipment. Did you get an EQ, Feedback Suppressor?? My CrownXTIs have DSP/EQ, but hard to use in real time to eliminate feedback...
Thx
that's what I always thought, but....my good friend got a job running sound with the biggest p.a. company in our hometown. He had been working for months before I came to check him out and when I looked at the board the peak lights were blinking all over the place!! When I asked about that he told me that's fine as long as there are not on constantly. Honestly, I think it depends on the board and you just have to read the manual because my Mackie board says it's a no-no.
Brian Warner stupid question: when you have a serious problem, what do you do?? HTH can you tell what channel it's on if half the board's goimg nuts??? Doh! lol.
How to identify which frequencies are causing the feedback?
The video is a great packed lesson against feedback. Apart from the definition of feedback (I find it a bit simplistic and questionable)
For me it is interesting your video because I work WITH feedback.
Some sound guys try to really max the gain level right at the edge of clipping , You can get away with this depending on you gear's over all capacity however I alway give myself a little gap just before clipping by allowing the meter to ride slightly into the yellow zone. If I hear any distortion in the speakers then I will back down on the gain. and try going up at the fader instead 0db is the safest though.
thanks man
Great info! Thank you! I'm experiencing feedback issues with my New DPA 4099g mic, I'm going straight to my AER amp using a mic cable to the mic channel, I also was hoping to use my Fishman EQ pedal using a mic to 1/4" cable (stereo type) and also the same going out to the regular guitar input on my amp, which in this case gives me more options with EQ, but for some reason I'm not getting any signal using these cables, I have a feeling that I maybe using the wrong type of cables. My EQ pedal is also phantom powered and can be used as a DI. Any help would be greatly appreciated. Thank you! Mehdi
Toquelibre curious about something, you didn't buy speaker cable, did you? It's fatter than unbalanced guitar cables. Unbalanced cables (for guitars/bass) has one stripe on the plug. Balances cables, used for keyboards and electronic drums, have two stripes. I seem to recall grabbing the speaker cable for guitars. THAT made a HORRIBLE sound as you describe. This is why you turn your trim (the knob at the top) down before you do anything! Don't do that at the faders, the sliders at the bottom, because the signal runs from the top of the mixer down, time your feedback loop will get notably louder.
Hey Jonas its Chris Morita hows it going? Great vids you posted take care.
Really nice vid and perfect lecture. :-)
I may commit that churches are really strong school and exam for this kind of issues. I totally agree with your hints but except one (naturally) ^^
In my humble opinion Gates are illusive and trappy helpers against feedback, at least under multi-mic conditions. As long as the gate(s) is/are closed, all is fine.
Open mic (at least opened gate) by speaker, singer, instrument or anything else, if forcing feedback, will raise the overall volume at the venue to volumes that will open the other gates too! So... once opened, all that channels will provide additional level to the feedback loop. This is true not only for the same frequencies as the already upcoming feedback freq, but for all others too. Caused by (at least) the same ground noise (whatever characteristics) every open mic spends into the chain.
Even critical when each of that mics has been safe under feedback level, but the sum may step over the feedback threshold! For years i've seen astonished FOH engineers in such situations, where a single feedback comes slightly up, and with each tens of a seconds it's getting more and more worse due to the further opening of gated mics on the same stage.
So - even in old churches (like we have in g'old europe *haha*) - doing faders by hand in critical sections (talk, interview, panel and board discussion, theater play or whatever) is still the best feedback control by lowering all mics by hand that are not needed at the moment. Just doing -8 dB or less per channel will save ears. Even if feedback occurs on one channel it can't raise the faders on channels closeby. :-D
Many greets from Germany! :-)
To clarify this: The post above just and only relates to the term "using gates against feedback". - in reality i'm great fan of gates and (smart driven) compressors. Gates keep the mix clean and straight! **thumbsup**
Timo Heinrich do they have mutes on the channels? You can shut those mics off you don't need, or just any effects while they're talking, too, on the returns.
When I set a vocalist's mic should I try to shoot for 0db on the LED Meter on the mixer ? I have an issue with another sound man he say that I do not use enough gain he says that it is ok for the meters to jump up above 0db or unity is this true ?
Thank you for this video...question for you. I'm new to working the soundboard and we've experience the low sweeling (woooowooo) type feedback, not the high pitched one like in this video. What's the cause of this type of feedback?
Still Feedback, but in the lower E.Q. Range - around 250Hz, 125Hz or 40Hz.
amazing tutorial. thank you
Ha ha haaa! Such a great feedback tutorial!