feedback when using condensor mics

[IA76]

Hi

 

We usually use 2 standard mics on a table on a small stage and this works fine.

 

We tried using 2 audio technica condensor mics in the same position as they are smaller and look a lot better but we get feedback when using them.

 

Why do we get feedback with the condensor mics?

 

Thanks

[johndenim]

What do you mean by "standard mic"?

If you are talking about say an SM58, the frequency response is around (IIRC) 50hz - 15 khz.

 

My Sennheiser 865 condenser is 50 hz - 20 khz.

 

Condensers are generally more prone to feedback as they are a lot more sensitive.

A bit of sensible EQing should sort out the problem.

 

See here.

[Rob_Beech]

There are lots more contributing factors.

 

Without knowing what "standard" mics and what condenser mics it's very difficult to tell what is causing it.

 

John makes a valid point that condenser mics tend to be more sensitive. But then again they should pick up more and thus the level you require should be lower.

 

Pick up pattern is important here, the people need to be speaking into the correct part of the mic else you'll not get a high enough signal, will turn the channel up, and get feedback.

 

Proximity, again without knowing what mics we can't advise where you may be going wrong. Some mics are designed to be used close up, others further a field. A lecturn mic is designed to be used at a distance (around a foot or so although their useable range is often quite manageable). An SM58 is designed to be used very close to the mouth. If you use either incorrectly you'll get abnormal results.

 

Lets have some model numbers and details of other equipment in use.

 

If people don't speak loudly enough you're fighting a losing battle. If your speakers are incorrectly positioned, you're covering walls and not ears, or you're not covering enough ears at a low volume and are having to boost the volume to get the sound to cover more people at the back at an acceptable limit, you are increasing your chances of feedback significantly.

[johndenim]

Rob as always offers excellent advice.

 

I'm thinking (if this is for speech only) that you would do better with some cheap lavs?

 

Cpc do one here for only £21.34 each.

[Rob_Beech]

or one here for £5.75. With the same connector.

 

That all said of course, I wouldn't recommend them for this scenario without knowing exactly what you were doing as in the wrong scenario it could make it much much worse.

 

The other thing to remember is that some of these require power, wired or wireless, they need to get the right power. so its often NOT a case of just putting an adaptor lead in and running it down under the table.

[johndenim]

I think we need some more input from the OP before we can move on?

[IA76]

I'm not sure of the technical terms for the mics but I'll try and explain.

 

By standard mics I mean normal handheld mics (I'm not sure if they are condensor mics as I can't see a model number on them but they are audio technica branded)

 

The mics that we get feedback with are Audio Technica gooseneck mics.

 

All mics go to a Peavey XRD 680 mixer which then goes to a 100v amp.

 

Volume levels on mixer are set at just over half.

[paulears]

Sorry - without the models, we're just guessing.

AT have a huge range of gooseneck condensers - some are omni (VERY bad for feedback reduction), some are ordinary cardioids (pretty much the same pick up pattern as a cardioid hand-held). They also have wider and narrower versions of the cardioids.

 

We really can't help without knowing what the 'problem'mic actually is.

[berry120]

If you really can't find the model number, try taking a photo and uploading it (some on here may be able to work out what they are from that.)

[IA76]

I'll sort some pictures out if I can't find the model number.