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Live sound reinforcment placement of microphone andspeaker..

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Anonymous
June 2, 2005 1:43:24 PM

Archived from groups: rec.audio.pro (More info?)

Hello. I have a question about the placement and routing of speaker,
versus microphone cables in live sound reinforcement situations. I've
done; quite a bit of recording in live club situations but not where I
am doing the sound. I usually route mic cables from behind the band for
instruements and split out from their vocal mics.

I'm going to provide both the PA and possibly record in a small club
situation. The stage depth (no stage really, to one side of the room)
is very small. Because of how small it is, when I have recorded bands
there it ends up in quite a cable mess. It's almost impossible to keep
microphone cables from being in close proximity to some of the speaker
cables, especially if any stage monitors are used.

Most bands there don't use stage monitors but because this will be
multiple bands, and I think a few of them will use accoustic guitars, I
may need the monitor for the accoustic guitars. Any suggestions for
routing the speaker cables? Especially as regards microphone cable
routing.

Mike http://www.mmeproductions.com
Anonymous
June 2, 2005 10:46:19 PM

Archived from groups: rec.audio.pro (More info?)

Yea the accoustical feedback there is another mess but I assume I will
just have to deal with it .Roll off the lows on the acoustic guitars or
whatever. I think maybe two artists will have acoustic guitars. I will
DI them but I know the body of the guitar can start to resonate from
the monitor output etc.

An interesting thing happened when i was recording a jazz trio live. I
wasnt doing anything with the PA. Was DI'ing and upright bass the guy
had running into a small Ampeg amp via what I think was more of a small
mic transducer on the bridge as opposed to some kind of Piezo or
magnetic coil type pickup. The guy was feeding back via his amp. He
insisted it was the DI causing the feedback. I assured him it wasn't
but took it out of the loop and put a mic on it. He continued to
feedaback. Looking at it in software later it was dead on at 205 hz.
They were playing in front of a wall with a hard smooth surface and
several good sized windows as well. I'm assuming it was a reflection
at that distance coming out to 205 hz wavelength, something around five
feet from the wall, as opposed to a room resonance, but I might be
wrong.


Mike http://www.mmeproductions.com
Anonymous
June 2, 2005 11:04:37 PM

Archived from groups: rec.audio.pro (More info?)

In article <1117730604.716820.93280@g44g2000cwa.googlegroups.com> mmeprod@mmeproductions.com writes:

> I'm going to provide both the PA and possibly record in a small club
> situation. The stage depth (no stage really, to one side of the room)
> is very small. Because of how small it is, when I have recorded bands
> there it ends up in quite a cable mess. It's almost impossible to keep
> microphone cables from being in close proximity to some of the speaker
> cables, especially if any stage monitors are used.

Running mic cables adjacent to speaker cables is rarely a problem,
assuming you have decent shielded cable, no broken shields, properly
wired connectors, and balanced mic inputs. (all of which is pretty
much normal for a well maintained system)

Just make sure people don't trip over the cables and pull your mic
stands over.


--
I'm really Mike Rivers (mrivers@d-and-d.com)
However, until the spam goes away or Hell freezes over,
lots of IP addresses are blocked from this system. If
you e-mail me and it bounces, use your secret decoder ring
and reach me here: double-m-eleven-double-zero at yahoo
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Anonymous
June 3, 2005 1:24:45 AM

Archived from groups: rec.audio.pro (More info?)

Mike Rivers wrote:
> Running mic cables adjacent to speaker cables is rarely a problem,
> assuming you have decent shielded cable, no broken shields, properly
> wired connectors, and balanced mic inputs. (all of which is pretty
> much normal for a well maintained system)

If you're feeling paranoid, you can try to avoid running the speaker
cables close to and in parallel with the mike cables -- separating them
helps (remember the inverse square law?) and the closer to a 90 degree
crossing you can get the less signal can get coupled from one wire to
another.

But your problem on a small stage is more likely to be acoustic feedback
than electrical feedback.
Anonymous
June 3, 2005 6:14:03 AM

Archived from groups: rec.audio.pro (More info?)

"transmogrifa" <mmeprod@mmeproductions.com> wrote in message...

> Most bands there don't use stage monitors but because this will be
> multiple bands, and I think a few of them will use accoustic guitars, I
> may need the monitor for the accoustic guitars. Any suggestions for
> routing the speaker cables? Especially as regards microphone cable
> routing.


If there's a monitor in the house, everyone will want access to it.
Use it (them) as a dividing line... run what's needed of the seaker
and monitor cabling on the outside of the wedge(s).

DM
Anonymous
June 3, 2005 6:40:18 AM

Archived from groups: rec.audio.pro (More info?)

"transmogrifa" <mmeprod@mmeproductions.com> wrote in message news:1117763179.224279.114540@z14g2000cwz.googlegroups.com...
> Yea the accoustical feedback there is another mess but I assume I will
> just have to deal with it .Roll off the lows on the acoustic guitars or
> whatever. I think maybe two artists will have acoustic guitars. I will
> DI them but I know the body of the guitar can start to resonate from
> the monitor output etc.
>
> An interesting thing happened when i was recording a jazz trio live. I
> wasnt doing anything with the PA. Was DI'ing and upright bass the guy
> had running into a small Ampeg amp via what I think was more of a small
> mic transducer on the bridge as opposed to some kind of Piezo or
> magnetic coil type pickup. The guy was feeding back via his amp. He
> insisted it was the DI causing the feedback. I assured him it wasn't
> but took it out of the loop and put a mic on it. He continued to
> feedaback. Looking at it in software later it was dead on at 205 hz.
> They were playing in front of a wall with a hard smooth surface and
> several good sized windows as well. I'm assuming it was a reflection
> at that distance coming out to 205 hz wavelength, something around five
> feet from the wall, as opposed to a room resonance, but I might be
> wrong.

I'd gladly wager that the player, especially jazz types, simply wanted you to
either mic his cabinet or his instrument. I prefer starting with a DI myself,
but your average jazz 'purist' is dead-set against it (and not without reason).
It likely had nothing at all to do with the feedback... I really don't see how it
possibly could, as long as you had a clean line split to his amp. Possibly
the room was influencing the situation, but I really sorta' doubt that too,
unless he was 30 feet from his rig and/or cranked waaay too far up.

I see a boatload of players that are so used to certain settings with thier
amps, and so familiar with the sympathetic frequencies between the rig
and the instrument, that they can simply pick up their bass and move it
a couple of inches one way or the other and lose the feedback.

--
David Morgan (MAMS)
http://www.m-a-m-s.com
Morgan Audio Media Service
Dallas, Texas (214) 662-9901
_______________________________________
http://www.artisan-recordingstudio.com
Anonymous
June 3, 2005 8:37:22 AM

Archived from groups: rec.audio.pro (More info?)

On 6/2/05 10:40 PM, in article mqPne.20128$tv3.1356@trnddc06, "David Morgan
(MAMS)" <mams@NOSPAm-a-m-s.com> wrote:

> I'd gladly wager that the player, especially jazz types, simply wanted you to
> either mic his cabinet or his instrument. I prefer starting with a DI myself,
> but your average jazz 'purist' is dead-set against it (and not without
> reason).

What reason? That their pickups dopn;t sound a thing like a bass? Not my
fault, especially when there ARE those out there that send a signal down the
wire that is GORGEOUS so it IS possible and not rocket scieince...
Rarely a reason not to DI... And you should mic the amp too.
But your 'some guys hate DI" was the cause of a recent mess. 10-piece jazz
band... Had a double bass and the guy refused a DI (band members knew him
and said to preserve sanity, humor him as he'll just unplug it when you walk
away) so we miced the bass itself and the amp... went with that first set.
We REALLY hated the idea though cause this guy had come in late at the end
of sound check with his bass and... (who could have thought)... A STOCK
1970's SUNN Colesium Bass head-and-matching-cabinet (2 18's?). I hadn't seen
the like since High School and NEVER with an acoustic bass. This ill wind
indeed really blew. At the cab he sounded like he was in another room behind
a wall. Useless. Loud. Amazing.
And the mic on the bass just picked up drums and percussion reflection off
the face. (like we didin;t guess... We were desperate to try and get
SOMETHING)
First set break he left stage and we managed a surreptitious tap off one of
two Mystery RCA Jacks on the back that actually fed clean signal from the
amp front end. Gave it to the PA guy as well.
Rest of the night things were MUCH better out front and on the track.
!