Jump to content
Why become a member? ×

Help Needed - PA advice please?


FuNkShUi
 Share

Recommended Posts

Ok, so somehow ive ended up being in charge of setting up our bands PA now.
Think i got lumped with it because im the one that ends up trying to improve levels in the mix etc.
So, in all honesty, i know the basics of setting up a PA. But nothing more.
In a practice, we all kind of face inwards to each other, and i have no problem getting the PA up to playing volume without any issues.
When we gig however, im struggling to get the same clarity and volume without feedback.
There are 4 vocals, a keyboard and a sax going into the mix
Now, im guessing the reason for feedback is because we are all facing the same way, and as a result the mics are facing the speakers causing feedback?
I end up trying to rectify this by turning the individual mic levels down, cutting the treble, and turning Master volume up, as far as possible without the feedback kicking in again.
Im well aware, this is probably not the way to go about this, so is there anything you could advise, to help?
Dont know if it makes a difference but we have a Yamaha EMX312SC PA, and Peavey infinity speakers
Thanks in advance for any advice/tips

Link to comment
Share on other sites

The PA speakers should be out in front of the band not behind the band - that way the mics will not be pointing towards the speakers. Usually, for convenience, the speakers are placed at each side of the stage in front of the band and the mics are placed behind the speakers. This placement will help reduce feeback but you will still get feedback if the volume is high enough.

With the speakers in this position you may find that the singers cannot hear themselves clearly enough. You can experiment with reducing the backline sound levels, adjust the speaker placement etc.

In big live sound setups this is where "stage monitoring" comes into play. A separate monitor speaker is placed in front of each signer (though still behind the mic) pointing directly to the singer and fed a mix that contains his/her vocals.

If it's just vocals that need this monitoring treatment you can try using this type of very small, mic-stand mounted monitor -

http://www.behringer.com/EN/Products/B205D.aspx

These are very small but very effective when used correctly (i.e. mounted on the signers mic stand and pointing directly at the singer).

Link to comment
Share on other sites

Great.
I assumed it was probably tht they should be in front, with no monitors though i was worried about the singer not being able to hear himself.
We are currently saving for a monitor, so this looks ideal. Thanks!!
Any settings on the EQ that would help a little bit?

Link to comment
Share on other sites

I'm no expert...far from it, but...

Yup - definitely speakers behind the mics.

In an emergency (drummer forgot to put the monitors in his car...!) I've used a line out from the EMX into a guitar combo as a monitor. Sounds a bit Heath robinson, but better than nothing. At least vox could hear something.

You might find that you can get more volume, before feedback, if you don't use the compressors on the inputs, or at least keep them turned well down.

For EQ, I start with everything on the inputs at 12 o'clock and the graphic flat, then get the desired EQ on the individual channels by cutting what I don't want, rather than boosting the rest.
Once the individual channels are set up (EQ & relative volume. I keep the channel gains as low as possible) I go louder than we need on the master. If I get feedback, cut the individual sliders right down on the graphic, one at a time, to find the offending band/s. Then up it again on the graphic until it's almost feeding back, but not quite, then bring the master volume down to where it'll be when we're playing.

If I've done this and the vocals aren't loud enough (not often a problem in the places I play) then tough. The backline has to turn down to suit. If the vocals can't be heard, or the audience is in pain due to feedback, you might as well not bother turning up, IMO.

Hope that makes sense. I'm no expert (far from it. Just the one who, like you, seems to have landed the role of soundman because I actually care about what we sound like) but it works for me...although we usually only have 2 x vox, and sometimes a bit of kick, going through the PA, so my situation is a bit more straightforward than yours.

Link to comment
Share on other sites

With regards to feedback I'd add, on the Yamaha EMX312SC don't use vocal compression more than absolutely necessary (and probably not at all), likewise reverb. It also has a small graphic eq, and you might be able to nudge the offending frequency down a little bit on that. (A good graphic eq would be an excellent investment when you get your monitor). Also make sure the singer is using a good quality mic; SM58s are ubiquitous for good reason.

Link to comment
Share on other sites

The process described above, of finding the individual frequencies that are feeding back, is often called 'ringing out' the monitors, as you'll hear a 'ringing' when you're close to feedback levels.
Although individual monitors, with their own mix, is close to ideal, one needs several monitors and several 'aux' channels, which you won't find on a smaller desk. A reasonable 'starter' compromise is to use 'side' monitoring, where the monitors are not directly in front of the singer, but placed at each side of the stage, slightly ahead of the mics, and pointing inwards, toward the band or along the line of mics. This enables the whole band to hear the vocals, with the downside of not being perfectly adapted to each singer.
Hope this helps...

Link to comment
Share on other sites

  • 2 weeks later...

Hiya,

Take *all* of 1kHz out of the graphic and you'll probably lose a lot of that feedback on your 58s...if there is any low rumble, take all of the 250Hz out as well (the vocals and sax don't need it, you can always boost the LF on the keys channel if it needs more low end retaining)...if the rig sounds too 'thinned out' with this extreme EQ, gradually bring a little of whichever frequency back in.

I don't know those particular Peavey cabs but would imagine they sound pretty scooped - in addition to what I suggested for the graphic you might want to drop the treble EQ and bass EQ on each channel by a small amount.

I know it might feel like you're cutting everything but doing this on the channels in moderation could be a good move especially if you don't have loads of experience with the graphic.

Remember you can always use one cab, the mixer and one 58 to spend a little time at home or rehearsal getting to understand what frequencies have what impact on your sound with that specific gear - this time will be well spent! I guess the feedback you're getting is mostly HF as your instincts were to cut the treble, so get someone to speak in the mic and listen especially to how 2kHz, 4kHz, 8kHz on the graphic affects the top end when either boosted (at low volume...very slowly and in moderation, careful not to hurt anyone's ears!) or cut.

Hope this helps!

Tom

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...