phase shifters aren't what you need.
Phase shifting won't get rid of feedback in a PA necesarily, unless the
feedback is at one very narrow frequency.
You can get feedback destroyers from Behringer for about the cost of a
couple microphones.
The Shark 110 is a decent single line automatic feedback suppresser. There
is also the behringer 1124 rack unit which has auto feedback suppressing
functions. Basically the unit detects the frequencies at which the mikes
are feeding back and uses very tight notch filtering to get rid of the
anoying feedback. It can eliminate multiple frequencies if necesary. It
can also learn and auto detect which means if you have someone moving around
in the near field of the speakers it will get rid of feedback as it appears
and then take out the notch filter when there is no longer feedback. The
notch filtering allows the over all tonal quality to remain the same as if
there were no filtering taking place. Most sound techs just utilize a 30
band EQ and use LED's to detect feedback and drop that particular frequency
down until the feedback goes away. This is tedious and can effect the tonal
quality of the sound quite a bit compared with notch filters.
The shark also has gaiting and compression built in....very useful for
unattended microphones that sometimes get a mind of their own and start
howling for no apparent reason. The gaiting will keep them quiet until
something loud enough gets them going.
73
Colin, V A6BKX
----- Original Message -----
From: "Brett Winches" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, April 03, 2008 7:31 AM
Subject: Re: Microphone question
> I just bought 4 SUM for use at our church and indeed they are great
> units. We run them through an EQ on the mix board and the idea was to
> have as close to identical units thereby reducing the knob twiddle
> effect for various board ops. We also have three Senheiser but I do not
> know the model numbers there. I used one in a PA last weekend and am
> impressed but we sure need some phase shifters to decrease feedback in
> that situation. Hard on the ears!
>
> =20
>
>
> =20
>
> Thank you!
> Brett Winchester KD7JN
> [log in to unmask]
> ICBVI -- Reading Services
> P O BOX 83720
> 341 W WASHINGTON STREET=20
>
> BOISE IDAHO 83720-0012
> 208-334-3220-104
> 208-639-8386 DID
> 208-334-2963 fax
>
>
> =20
>
> =20
>
>
> -----Original Message-----
> From: For blind ham radio operators
> [mailto:[log in to unmask]] On Behalf Of Colin McDonald
> Sent: Thursday, April 03, 2008 3:16 AM
> To: [log in to unmask]
> Subject: Re: Microphone question
>
> any studio mike will sound pretty decent on SSB.
> Most studio mikes, even the cheap ones will give you an audio frequency
> range of at least 50HZ to 16KHZ.
> Since your typical 2.7K maximum band width on ssb will be quite a bit
> narrower then that, you can be sure that the mike will give a good flat
> response within the bandwidth that the radio puts out.
> Audio technica, V-tech, AKG, CAD, Nady, shure, among several others all
> sell quality studio mikes for around 30 to 60 bucks.
> If you want a really high quality mike for vocal audio, the shure
> beta-58 is about the best on the market right now under $500.
> It's around the same price as the Heil Gold line, in the $150 to $199
> range.
> The idea is to have as flat a response out of the microphone as
> possible, and then contour the response with a graphic Equalizer.
> Some of the cheaper mikes will have bumps at 1K or 2K to increase
> intelegability on a PA, but the better ones will be flat.
> I use a shure sm 158 from time to time on the ts2000 straight in and get
> good results.
>
> Look around for an old style desk lamp that has a double action boom on
> it.
> They often have a shelf clamp on one end, and you can modify the other
> end to hold a mike clip.
> You should be able to locate a goose neck with a clamp on one end for
> studio control room or DJ use.
> Sometimes you have to get a few different parts and build the thing to
> suit your needs.
>
> 73
> Colin, V A6BKX
> ----- Original Message -----
> From: "John Miller" <[log in to unmask]>
> To: <[log in to unmask]>
> Sent: Wednesday, April 02, 2008 5:09 PM
> Subject: Microphone question
>
>
> > Hi all, I'm sure someone in here has to be using a broadcast mic, or
> heil
> > gold line, mic, either with their ham radio station, or for music, or
> maybe
> > broadcast radio. I just picked one up, that MC-60 really got on my
> nerves,
> I
> > could not get it like I wanted with out bypassing the base completely,
> so
> > W2IHY suggested a professional mic that's very inexpensive and sounds
> great.
> > Looks like it's a lot more expensive than it is too, I mean, I paid
> $30
> > including shipping for the thing and the audio reports are incredible.
> > Reviews on www.eham.net are as well. Anyway, I'm looking for a decent,
> not
> > too expensive boom mount. Something I can clamp to my desk and it will
> put
> > the mic right in front of me. I've looked and I'm not sure what's what
> but
> > this little desk stand I have really stinks and I'd like something
> that I
> > can bring in front of me a little closer when I sit back and relax in
> my
> > chair. Does anyone know of anything like that I might look in to? I'm
> sure
> > there is such a thing but I've never looked before and some things
> sound
> > close but I'm not sure and can't spend money to find out it's not even
> close
> > as it sounds. Thanks.
> > John Miller N1UMJ
> > AIM and yahoo messenger: N1UMJ Skype: n1umjjohn
> > home page:
> > http://home.comcast.net/~n1umj/wsb/html/view.cgi-home.html-.html
> > myspace: http://www.myspace.com/n1umj
> >
> >
> >
> > --=20
> > No virus found in this incoming message.
> > Checked by AVG.
> > Version: 7.5.519 / Virus Database: 269.22.4/1355 - Release Date:
> 4/1/2008
> 5:37 PM
> >
> >
>
>
>
> --
> No virus found in this incoming message.
> Checked by AVG.
> Version: 7.5.519 / Virus Database: 269.22.4/1355 - Release Date: 4/1/2008
5:37 PM
>
>
|
