ORTF + Mid?

[Dave Brown]

Hi All,

I'm experimenting with better ways to capture acoustic guitar and
voice, tracked simultaneously. I've tried various placements of LDC to
capture voice and 2 SDCs to capture a stereo image of guitar. But I'm
never happy with the sound of a close-miked acoustic guitar, nor the
pseudo-stereo image I can generate.

So now I'm trying a different approach. I'm placing the LDC to capture
a reasonable mono mix of the voice AND guitar, and using my two SDCs
in an ORTF config, mostly to capture room ambience in stereo.

I wonder if there are any pitfalls I should watch out for? Any offhand
thoughts about mike placement?

I need to do a bunch of experimentation still, but where I am right
now is (me seated): the LDC about 3' away and 3' from the floor, and
the ORTF pair about 5' away and 4' from the floor. The imaging sounds
OK, but still working on getting the right tonal balance on the
guitar. A never ending quest!

FWIW, the LDC is a CAD M9, and the SDCs are KM-184s. I'm recording in
a room about 15' x 14' x 10', hardwood floor with a heavy rug under
the recording position, pretty much bare walls except some tube trap
panels to deal with flutter echo. And a queen bed bass trap. :-)

Also, I'm using a pretty cheesy $8 stereo bar, and it's hard to get
the 7" AND 110 deg angle on the mikes -- I get more like 10". Any
recommendations for a better ORTF bar that doesn't cost more than an
arm?

As always, thanks very much for any advice, and for the ongoing great
info I get here.

Regards,

dB

[Peter Larsen]

Dave Brown wrote:

> I'm experimenting with better ways to capture acoustic guitar
> and voice, tracked simultaneously.

1 stereo pair, 5 feet away.

> I've tried various placements of LDC to capture voice and
> 2 SDCs to capture a stereo image of guitar. But I'm
> never happy with the sound of a close-miked acoustic guitar,

Generally you can NOT EVER expect a balanced sound from anything if you
are closer to it that its size. So close up = 3 feet away.

> So now I'm trying a different approach.

Overdub. You can not sing correctly while you play an instrument, just
one reason is that you have to sit to play the guitar well.

> I'm placing the LDC to capture a reasonable mono mix of
> the voice AND guitar, and using my two SDCs
> in an ORTF config, mostly to capture room ambience in stereo.

ORTF is defined by the inter capsule distance being 110 degrees, it is
thus not usable close to the source, closer to the source you need to
angle the mics less apart. XY is generally a better wording, XY need not
be one-point.

> I wonder if there are any pitfalls I should watch out for?

Stop being a purist the wrong way around. Record the guitar with a
stereo pair 3 feet away and with a stereo pair 6+ feet away, did that
once in my living room, worked fine. Then record the vox with a suitable
mic about 3 feet away and if possible keep the distant stereo pair for
similar ambience. You do end up with 7 tracks tho' ... I haven't
actually tried it, but Kristal might be the software that can do the job
at a cost you like.

> FWIW, the LDC is a CAD M9, and the SDCs are KM-184s.

I don't know what a CAD M9 is, and I can live happily without knowing
it, the mic that matches a pair of KM184's is a KM184. By overdubbing
that gets to be an option. The point of having the distant pair on both
parts of the recording is not only to get room ambience, but also to add
whatever reverb as may be deemed beneficial to those tracks ....

> Also, I'm using a pretty cheesy $8 stereo bar, and it's hard to get
> the 7" AND 110 deg angle on the mikes -- I get more like 10". Any
> recommendations for a better ORTF bar that doesn't cost more than an
> arm?

FORGET about that silly angle spec used once upon a time by a guy in
france that could not get his stereo pair close enough to the orchestra.
If that angle works, then you are in my im-modest opinion quite likely
to be too far away.

Turn you ears on and listen to what happens with the stereo perspective
when you change that angle. The stereo bar you use is excellent, do
however be aware that having the intermic distance smaller = reducing
the angle, you can use both ways to adjust the stereo image, an
adjustable stereo bar may thus be a very pleasant additition to your
toolkit.

See my site for a pic of an XY pair in the context of an actual location
recording, notice the moderate intermic angle used to get a good stereo
spread of the fairly wide stage.

Back in 1983 (I think) there was an excellent paper in the JAES, called
"The Stereophonic Zoom", you may want to search for on the AES site, it
may be possible to order it, I keep forgetting the name of the author,
but someone out there may recall it.

> dB


Kind regards

Peter Larsen

--
*******************************************
* My site is at: http://www.muyiovatki.dk *
*******************************************

[Paul Stamler]

Dave Brown > wrote in message
om...

> So now I'm trying a different approach. I'm placing the LDC to capture
> a reasonable mono mix of the voice AND guitar, and using my two SDCs
> in an ORTF config, mostly to capture room ambience in stereo.
>
> I wonder if there are any pitfalls I should watch out for? Any offhand
> thoughts about mike placement?
>
> I need to do a bunch of experimentation still, but where I am right
> now is (me seated): the LDC about 3' away and 3' from the floor, and
> the ORTF pair about 5' away and 4' from the floor. The imaging sounds
> OK, but still working on getting the right tonal balance on the
> guitar. A never ending quest!

You may want to move the LDC closer, perhaps to 2'. Your room sounds
difficult, and you'll probably be better off with a higher ratio of
direct-to-ambient sound in your main microphone.

> FWIW, the LDC is a CAD M9, and the SDCs are KM-184s. I'm recording in
> a room about 15' x 14' x 10', hardwood floor with a heavy rug under
> the recording position, pretty much bare walls except some tube trap
> panels to deal with flutter echo. And a queen bed bass trap. :-)

I'd invest in some sound-treatment ASAP. Foam if you can afford it, pink
fiberglass in frames if you can't. (See F. Alton Everest's books for
designs.) Wear gloves and a mask when you handle that stuff.

> Also, I'm using a pretty cheesy $8 stereo bar, and it's hard to get
> the 7" AND 110 deg angle on the mikes -- I get more like 10". Any
> recommendations for a better ORTF bar that doesn't cost more than an
> arm?

I use the AKG one which is made by somebody else, the one with two swinging
arms attached to a short central bar. Beyer sold it too. Shure's heavy
cylinder does a good job too.

Peace,
Paul

[Chris Hermann]

> Overdub. You can not sing correctly while you play an instrument, just
> one reason is that you have to sit to play the guitar well.
>
> Stop being a purist the wrong way around.
In my experience it is sometimes not possible to get a good separate
performance from singer/songwriters who are used to playing and singing
at the same time.
We almost always decided that the feel of the playing was more important
than a better sound.

[Mike Rivers]

In article > writes:

> You may want to move the LDC closer

Oh, no, not you too, Paul.

Help stamp out the use of the abbreviation "LDC."

"Microphone" will do fine, and the make and model of the microphone is
even better.


--
I'm really Mike Rivers )
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

[Chris Hornbeck]

On Tue, 09 Mar 2004 10:25:08 +0100, Peter Larsen
> wrote:

>Back in 1983 (I think) there was an excellent paper in the JAES, called
>"The Stereophonic Zoom", you may want to search for on the AES site, it
>may be possible to order it, I keep forgetting the name of the author,
>but someone out there may recall it.

Michael Williams. Available on a paper from Rycote or from
Sounds of Scotland.

Chris Hornbeck

"Second star to the right,
Then straight on 'til morning."

[Dave Brown]

Chris Hermann > wrote in message >...

> > Overdub. You can not sing correctly while you play an instrument, just
> > one reason is that you have to sit to play the guitar well.
> >
> > Stop being a purist the wrong way around.

> In my experience it is sometimes not possible to get a good separate
> performance from singer/songwriters who are used to playing and singing
> at the same time.
> We almost always decided that the feel of the playing was more important
> than a better sound.

Exactly. I should have specified, but I'm playing complicated
fingerstyle blues/country/jazz arrangements where the vocals and
guitar play off each other. Impossible to get an appropriate
performance by tracking the guitar by itself.

I agree that it's better for the voice to stand, and that's what I do
on some tunes.

dB

[Garthrr]

someone said:

>You can not sing correctly while you play an instrument,

Oh yeah? Tell that to Aretha Franklin.

<<just one reason is that you have to sit to play the guitar well.>>

Where do you get this stuff? What about Robben Ford, Jimi Hendrix, Pat Metheny,
Bela Fleck (banjo, I know), John Scofield, Eric Clapton etc, etc, etc. Sheesh!

Garth~


"I think the fact that music can come up a wire is a miracle."
Ed Cherney

[Dave Brown]

"Paul Stamler" > wrote in message >...

Thanks for the helpful comments, Paul (and everyone).

> You may want to move the LDC closer, perhaps to 2'. Your room sounds
> difficult, and you'll probably be better off with a higher ratio of
> direct-to-ambient sound in your main microphone.

I'll try that. I don't want to get too close, because I figure at some
point the guitar sound will suffer.

> I'd invest in some sound-treatment ASAP.

I'm ordering some Sonex Fabritec panels for the room. These are 1.5"
thick foam panels with fabric covering (so they look decent). They're
not very effective below 250 Hz, but for what I'm recording I don't
think it matters. Any thoughts on how much coverage I'll need? Right
now I'm budgeting to cover about 12% of the wall surface area (eight
2' x 4' panels), nothing on the ceiling, and I can put more rugs on
the floor if need be.

> I use the AKG one which is made by somebody else, the one with two swinging
> arms attached to a short central bar. Beyer sold it too. Shure's heavy
> cylinder does a good job too.

I'll look into those, thanks. AEA sells some beauties, but they're
almost as expensive as my mid-line mikes!

Dave

[Paul Stamler]

Dave Brown > wrote in message
om...

> I'm ordering some Sonex Fabritec panels for the room. These are 1.5"
> thick foam panels with fabric covering (so they look decent). They're
> not very effective below 250 Hz, but for what I'm recording I don't
> think it matters.

Keep in mind that the low note on a guitar is 84Hz, lower if you do
non-standard tunings.

> Any thoughts on how much coverage I'll need? Right
> now I'm budgeting to cover about 12% of the wall surface area (eight
> 2' x 4' panels), nothing on the ceiling, and I can put more rugs on
> the floor if need be.

Check out some of F. Alton Everest's books on how to calculate reverb times.
Something he cautions against is the use of too many absorbents that absorb
high frequencies but not lows; good way to get a dull, muddy or boomy room.

Peace,
Paul

[Scott Dorsey]

Dave Brown > wrote:
>"Paul Stamler" > wrote in message >...
>
>Thanks for the helpful comments, Paul (and everyone).
>
>> You may want to move the LDC closer, perhaps to 2'. Your room sounds
>> difficult, and you'll probably be better off with a higher ratio of
>> direct-to-ambient sound in your main microphone.
>
>I'll try that. I don't want to get too close, because I figure at some
>point the guitar sound will suffer.

Figure-8 pattern. Vocal in the lobe of the mike, guitar in the null. If
you do it carefully, you can get a very clean vocal sound with no audible
guitar leakage.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Dave Brown]

"Paul Stamler" > wrote in message >...

> Keep in mind that the low note on a guitar is 84Hz, lower if you do
> non-standard tunings.

Yeah, down to ~70 Hz for a low D. I was thinking that an acoustic
guitar can't put that much LF energy into the room (like an electric
or bass guitar cabinet would), so LF absorption would not be as
necessary. Am I misguided?

I do have a couple of 16" full-round tube traps that a buddy gave me
when his girlfriend moved in :-). I'll put these in the room and see
if they make a difference.

> Check out some of F. Alton Everest's books on how to calculate reverb times.
> Something he cautions against is the use of too many absorbents that absorb
> high frequencies but not lows; good way to get a dull, muddy or boomy room.

Will check it out. Thanks again, Paul.

Dave

[Paul Stamler]

Dave Brown > wrote in message
om...
> "Paul Stamler" > wrote in message
>...
>
> > Keep in mind that the low note on a guitar is 84Hz, lower if you do
> > non-standard tunings.
>
> Yeah, down to ~70 Hz for a low D. I was thinking that an acoustic
> guitar can't put that much LF energy into the room (like an electric
> or bass guitar cabinet would), so LF absorption would not be as
> necessary. Am I misguided?

Kinda, yeah. It's not a question of quantity; it's a question of balance,
and standing waves. Small rooms have the unfortunate tendency to have a few
bass frequencies where they provide lots of support to the instrument, with
gaps between them where they don't, so you get bass-frequency "wolf notes",
with otherwise thin sound. Some absorption down there will at least help
even things out (as I recall, you had two dimensions that were in a 3/4
ratio, a potential problem -- or is my memory failing?)

Also, the problem of a dull and boomy room (when you have absorption in the
mids and highs but not in the bass) applies to any instrument, or voice.
It's made worse when you do distant miking. You may find the tube traps very
useful.

Peace,
Paul

[Dave Brown]

(Scott Dorsey) wrote in message >...

> >I'll try that. I don't want to get too close, because I figure at some
> >point the guitar sound will suffer.
>
> Figure-8 pattern. Vocal in the lobe of the mike, guitar in the null. If
> you do it carefully, you can get a very clean vocal sound with no audible
> guitar leakage.
> --scott

Figure-8 because the lobe tends to be tighter than a cardioid?

[Scott Dorsey]

Dave Brown > wrote:
(Scott Dorsey) wrote in message >...
>
>> >I'll try that. I don't want to get too close, because I figure at some
>> >point the guitar sound will suffer.
>>
>> Figure-8 pattern. Vocal in the lobe of the mike, guitar in the null. If
>> you do it carefully, you can get a very clean vocal sound with no audible
>> guitar leakage.
>
>Figure-8 because the lobe tends to be tighter than a cardioid?

Absolutely. A good figure-8 will have a very, very tight null and it
will extend for an entire plane around the microphone. A cardioid will
have much less of an audible null and it's only useable directly behind
he mike.
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."

[Hal Laurent]

"Dave Brown" > wrote in message
om...
> (Scott Dorsey) wrote in message
>...
>
> > Figure-8 pattern. Vocal in the lobe of the mike, guitar in the null.
If
> > you do it carefully, you can get a very clean vocal sound with no
audible
> > guitar leakage.
> > --scott
>
> Figure-8 because the lobe tends to be tighter than a cardioid?

That, and it's darn near impossible to put the vocal in the null of a
cardioid
guitar mike when the singer is playing the guitar.

Figure-8 patterns are your friend.

Hal Laurent
Baltimore

[Dave Brown]

(Scott Dorsey) wrote in message >...

> >Figure-8 because the lobe tends to be tighter than a cardioid?
>
> Absolutely. A good figure-8 will have a very, very tight null and it
> will extend for an entire plane around the microphone. A cardioid will
> have much less of an audible null and it's only useable directly behind
> he mike.

So, I'm still getting my head around the use of a figure-8 pattern.
Since there are two lobes, on either side of the mike, I assume I'll
position the mike so one lobe faces the singer's mouth (duh), the
opposite lobe points across the room (and hence I need to worry about
noise-producing equipment and unwanted room ambience on this side). So
that leaves a null that is like a cylinder with a center line through
the middle of the 2 lobes -- do I have this right?

OK, on to my choices for multipattern mikes -- all I have are
cardioids at present. At the low end, the AT4050 comes to mind. Are
there any other mikes in the $1000-and-below range that you can
suggest I take a listen to? Or with multipatterns, do you only start
getting something good closer to $2K?

Thanks,
Dave

[Carey Carlan]

(Dave Brown) wrote in
om:

> So, I'm still getting my head around the use of a figure-8 pattern.
> Since there are two lobes, on either side of the mike

There is ONE lobe in a toroid shape (like a doughnut) around the mic.
Assuming a side address mic, it circles top to bottom like a halo.
Anything above, below, left, or right (anywhere but front and back) is in
or near the null.

[Hal Laurent]

"Dave Brown" > wrote in message
om...
> (Scott Dorsey) wrote in message
>...
>
> > >Figure-8 because the lobe tends to be tighter than a cardioid?
> >
> > Absolutely. A good figure-8 will have a very, very tight null and it
> > will extend for an entire plane around the microphone. A cardioid will
> > have much less of an audible null and it's only useable directly behind
> > he mike.
>
> So, I'm still getting my head around the use of a figure-8 pattern.
> Since there are two lobes, on either side of the mike, I assume I'll
> position the mike so one lobe faces the singer's mouth (duh), the
> opposite lobe points across the room (and hence I need to worry about
> noise-producing equipment and unwanted room ambience on this side). So
> that leaves a null that is like a cylinder with a center line through
> the middle of the 2 lobes -- do I have this right?

The deepest null is more like a plane that is perpendicular to a line
going through the front and back of the mike. If you have your
figure-8 pattern mike on a stand with the front facing forward, the
null is strongest above, below, and to either side of the mike.

> OK, on to my choices for multipattern mikes -- all I have are
> cardioids at present. At the low end, the AT4050 comes to mind. Are
> there any other mikes in the $1000-and-below range that you can
> suggest I take a listen to? Or with multipatterns, do you only start
> getting something good closer to $2K?

The Shure KSM 44 is similar to the AT 4050, although my gut feel
is that the AT 4050 is a little flatter. I should drag one of each down
to Ty Ford's place sometime for a shootout.

Hal Laurent
Baltimore

[Hal Laurent]

"Carey Carlan" > wrote in message
. 203...
> (Dave Brown) wrote in
> om:
>
> > So, I'm still getting my head around the use of a figure-8 pattern.
> > Since there are two lobes, on either side of the mike
>
> There is ONE lobe in a toroid shape (like a doughnut) around the mic.
> Assuming a side address mic, it circles top to bottom like a halo.
> Anything above, below, left, or right (anywhere but front and back) is in
> or near the null.

I believe that when Dave said "lobes", he was referring to the pickup
pattern, not to the null.

Hal Laurent
Baltimore

[Garthrr]

In article >, "Hal Laurent" >
writes:

>The Shure KSM 44 is similar to the AT 4050, although my gut feel
>is that the AT 4050 is a little flatter. I should drag one of each down
>to Ty Ford's place sometime for a shootout.

I find the KSM 44 much brighter in the (I'm guessing at frequencies here)
5-8kHz area than the AT4050. The KSM 44 has a pretty biting high end. I find it
too sibilant for many singers. I like both mics but I consider them to sound
pretty different.

Garth~


"I think the fact that music can come up a wire is a miracle."
Ed Cherney

[Dave Brown]

"Hal Laurent" > wrote in message >...

> I believe that when Dave said "lobes", he was referring to the pickup
> pattern, not to the null.

Whew, thanks, Hal! I was going through some mental gymnastics trying
to figure out how a figure-8 mic could have a doughnut-shaped pickup
pattern.

Think I'll stay away from the Shure if it's at all prone to nasality
-- this white guy singing blues is particularly sensitive to that!