PA feedback problem

N

neoblasted

New member
Hi,

We play in a small room, rock music, we have a Drum, Bass, singer and guitarist. The Problem is the singer doesnt sing loud enough, and the PA we are using is not loud enough.

This is a cheap PA (300 watts Peak)
To make her hear herself I have to raise the volume at MAX on the PA, and I also have to increase the gain of the mic preamp, which cause a lot of feedback. So I was wondering, If I buy , lets say a 250-500 watts RMS PA, will it reduce the chances of feedback if I lower the GAIN, since the mic will be less sensitive ?

By the way we tried several position for the PA and same problem.


Thanks
 
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Feedback is not caused by the size, or watts of the PA, it is simply a frequency making a loop from the speaker to the mic,rinse and repeat. you can correct it to some degree by moving the speakers so they are not facing the mic, or move them further away, find the freq that is causing the problem and notching it out a bit. and turn everything down so you can have more control over the vocal. until you remove the feedback a bigger PA will only make it worse. :D
 
Loudest sound at the mic wins, period. Gain is gain whether you get it from the preamp or the power amp. Your plan won't work.

Options are: sing louder, sing closer to the mic, change speaker/mic placement, eq the monitor mix, play more quietly, use drum shields, add acoustic treatment to the stage area, IEMs.

Main speakers should be pointed at the audience and not at the microphones, each monitor speaker should be in the null of the relevant mic, aimed at the singer's head.
 
bouldersoundguy said:
Loudest sound at the mic wins, period. Gain is gain whether you get it from the preamp or the power amp. Your plan won't work.

Options are: sing louder, sing closer to the mic, change speaker/mic placement, eq the monitor mix, play more quietly, use drum shields, add acoustic treatment to the stage area, IEMs.

Main speakers should be pointed at the audience and not at the microphones, each monitor speaker should be in the null of the relevant mic, aimed at the singer's head.
Click to expand...

I was waiting on you to chime in Boulder:D And OP he is correct!;)
 
Cardiod mic pointed away from the speaker and preferably not pointing tight at the drums and/or amps. Vocalist eating the microphone. Don't cup the mic. EQ the mic! Pull out all of the low frequencies that will almost always be more instrument bleed than meaningful vocal. Focus that mix on the upper mids where intelligility lives and use less of the PA's headroom amplifying the bass and drums.

I've had times where it seemed like the monitor was reflecting off of my face or something so that it wouldn't feedback until I stepped up to sing. Singing across the mic rather than straight on in helps that some.

In really difficult situations you could try wiring one speaker out of phase (easy with banana plugs) so that they null at the microphone. That can make it sound funny, and might just change the frequency that feeds back, but it might help.
 
Ah, the usual 'stuck between rock and a hard place'. The best drummers hit hard (IMO anyway). But then you have to hear over that. So guitar players turn up, bass player turns up and then more guitar. Suddenly the vocals from even one with balls out volume are not audible in a rehearsal environment because of the feedback.

What is the exact model of the PA you are using? Are you only using it for vocals? If only for vocals or you have means from the unit to send a headphone output with only the vocals, you may save the singers voice by having her in headphones during rehearsal so she doesn't strain and destroy her voice.

If you need her to be loud in the room while rehearsing, well that can be tough. A separate headphone amp with multiple outs for those of you that need to hear her may be an option. Simple feeding it the vocal signal and those that need to hear her have that option to crank her up. But then there can be the 'now I can't hear myself' thing... That really depends on what is fed to what mixer/PA and what it has for options.

From decades of playing in bands, I have dealt with this over and over. Glad I am done with that now... Though I miss the gigs.
 
If this is about a rehearsal space the problem is most likely the small room and bad acoustics, though of course drums/amps volume is also part of the problem. Headphones/IEMs may be the only real solution.

I should have expanded a bit on "loudest sound at the mic wins" because it's not obvious to some that if the instrument bleed into the vocal mic is bad enough then when you turn the mic up in the monitors you get even more instruments. You're not just having to hear over the band's natural sound, you're actually amplifying the instruments in the monitors when you try to turn the vocal up. In that situation avoiding aiming the mic at the band can help if it's an option, but when the room is small there's really no place to aim the mic that isn't a source of bleed.
 
bouldersoundguy said:
If this is about a rehearsal space the problem is most likely the small room and bad acoustics, though of course drums/amps volume is also part of the problem. Headphones/IEMs may be the only real solution.

I should have expanded a bit on "loudest sound at the mic wins" because it's not obvious to some that if the instrument bleed into the vocal mic is bad enough then when you turn the mic up in the monitors you get even more instruments. You're not just having to hear over the band's natural sound, you're actually amplifying the instruments in the monitors when you try to turn the vocal up. In that situation avoiding aiming the mic at the band can help if it's an option, but when the room is small there's really no place to aim the mic that isn't a source of bleed.
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I just gathered that it was a rehearsal space issue as nothing was mentioned about recording anything. Plus the whole PA thing. :)

Sushi! :)
 
jimmys69 said:
I just gathered that it was a rehearsal space issue as nothing was mentioned about recording anything. Plus the whole PA thing. :)

Sushi! :)
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My first impression was live performance.

Mm, sushi. Tell you what, you're the connoisseur so I'll drive to your choice anywhere in Denver metro.
 
It is a hard lesson to learn and many never do and ever struggle but the fact is the loudness your singer can make before feedback is the BASE LINE sound level of the band! ALL else has to cowtow to that level.

This assumes of course that you want the audience to actually hear the lyrics? I have heard innumerable bands where they clearly don't!

Dave.
 
It was kind of skimmed past, but some decent acoustic treatment in the room could go a long way also. Just to have less of everything bouncing around and ending up in the vocal mic.
 
If the band has problems during rehearsal it will have the same problems live. I used to do a lot of live sound and the amount of times I could not get the vocals in the mix because of a quiet singer and loud band was countless. Friends of the singer running up saying, "I can't here the singer" and when you solo the vocal mic in the headphones all thats there are the drums and guitars and a whispering vocal. I have had the same thing when recording a live show where we get the recording back to the studio and the vocal track is full of messy bleed with hardly any vocal, and don't get me started about backing vocals that are sung 3 feet from the mic.

The mic hears whats there, practice with less volume you will need to do this at a gig.

Alan.
 
neoblasted said:
Hi, the PA is only for the singer. and it is a really cheap PA. Total PAâ„¢ - All-In-One Bluetooth Loudspeaker - ION Audio - Dedicated to Delivering Sound Experiences
So I guess even if I get a better and more loud speaker, say 1000 watts Peaks, I will still have the feedback problem ? My only option would be then to install a second amp acting like a monitor on the floor pointing the singer, and then other PA pointing to the rest of the band ?
Click to expand...

I thought so. Yes you could try to add a monitor speaker directed toward your singer but that depends on the room you are in as to if that will even make a difference. Adding more power to a PA system will not give it the ability to feedback less.

What is the size of your rehearsal space?
 
???! Giving the singer foldback will make them sing even quieter! We used to use a small speaker behind the MOC (in the PA caravan, country fairs) to stop him blasting the mic.

Push comes to it, you could try the old dodge of a pair of 58s taped nose to tail and out of phase but it won't sound nice.

Dave.
 
Gain before feedback is fixed until you change the physical setup. Extra power just means the feedback happens at a different position on the fader. You can experiment with different monitor positions. Cardioid mics give best gain before feedback when the the monitor is in the null. Hyper Cardioids need different wedge positions or feedback very easily, but once you get speakers in the mic null, the narrower capture area gives a bit more volume IF your vocalist is controlled and understands how to work the mic. Make sure how you place people on stage removes very loud sources from behind her.

Perhaps it would help her to have hotspot type monitors on her mic stand? In our band we use only our monitor system for rehearsals, because they are the constant. What goes through the PA we can't hear at the gigs so in a small room just pointless. I found that my monitors had to be so loud, to get over e drums and guitar that my ears hurt. I moved to IEMs. On stage volume is loud for the rest and it spills.

If you have a cheap/low power but nice sounding PA, how are the band going to hear the singer at the gigs? In rehearsal you can use it like monitors, but at a real gig, you can't do that. You are going to have to have a serious rethink and maybe spend money. Speakers for audience and speakers for the band. Somebody good to work them, and the best comment was the one that says about how the audience won't hear it either. Your pa and monitors MUST be capable of working at the bands lowest functional volume. If your music involves thick drum sticks and real guitar feedback, then your PA must be sized accordingly. PA system turned up too loud also sound horrible. Money, sadly, may be your only solution.
 
Lot's of good advice above but a couple of other thoughts.

First, I've found that a Sennheiser E835 is actually better at feedback rejection than an SM58. If you can borrow one to try, worth a shot.

Playing with the aiming of your speakers can often help more than you'd guess.

Finally, most bands put their output(s) through a 31 band GEQ and "ring out" the system, i.e. reducing the EQ on 3 or 4 bands most prone to feedback. Obviously you can't cut too much without affecting your sound but you can usually buy 6dB or so.
 
Thanks for all the good tips guys, I will rent a louder PA just to compare with, and get a EQ to ring out the room. The nasty feedback always seem to be in the 2.2 Khz and 5 Khz.
also we are not ready for gigs, what we want is having fun without that annoying feedback, we've been having this problem for one 1 year now, sometime we are lucky I am able to pinpoint the best EQ settings (3 bands settings) but sometime, everything I try just doesn't work. (Its like it depend of the weather outside) hahahah.

Thanks again
 
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