Reply
 
Thread Tools Display Modes
  #41   Report Post  
Posted to rec.audio.pro
Gary Eickmeier Gary Eickmeier is offline
external usenet poster
 
Posts: 1,449
Default Fascinating MS


"John Williamson" wrote in message
...

You could try altering the EQ on the S channel to alter the relative
levels of the HF percussion. If it moves in and out, you've got a
frequency response problem. Then you need to find out how much is the room
and how much is the microphones.


--
Tciao for Now!

John.


Actually, Scott is probably the most correct because it is a fairly tubby
room (almost echoey). So what I should do is a new series of tests outdoors
when it is quiet outside. I can easily do MS and then XY and see just where
the problem lies, in the mikes or in the room.

Gary


  #42   Report Post  
Posted to rec.audio.pro
hank alrich hank alrich is offline
external usenet poster
 
Posts: 4,736
Default Fascinating MS

Gary Eickmeier wrote:

I
am using the Audio Technica 2050 variable pattern mikes in Fig 8 pattern.
These are reasonable quality for a beginner like me and I would expect that
would work reasonably well, and maybe my MS mix isn't quite perfiect yet.


Off-axis response is important for your purposes, and smooth off-axis
response is often difficult to find, even more so with inexpensive
LDC's.

--
shut up and play your guitar * HankAlrich.Com
HankandShaidriMusic.Com
YouTube.Com/WalkinayMusic
  #43   Report Post  
Posted to rec.audio.pro
Tom McCreadie Tom McCreadie is offline
external usenet poster
 
Posts: 205
Default Fascinating MS

John Williamson wrote:

You could try altering the EQ on the S channel to alter the relative
levels of the HF percussion. If it moves in and out, you've got a
frequency response problem.

But altering the HF equalization on the S channel - or the M channel, for that
matter - will _always_ make the imaging of HF components move in or out. That's
pure physics, and such a phenomenon would also occur with perfect mics, so one
can't use such an experimental outcome to draw a conclusion on Gary's case.

His AT mics may well have an uneven off-axis response, but he was employing two
fig8 mics, so if the AT manufacturing process results mainly in a systematic-
rather than random frequency response skew in the mic patterns, there may be a
fortuitous "close-tolerance unevenness-matching" :-) between M and S mics, that
would provide a mitigating effect.

An ideal Fig8 MS with -3dB S gain equates mathematically to a Fig8 XY pair
splayed at 35.3. That would have a Sengpiel SRA of 47.7 (with the
ambiophonic region beginning beyond 54.7). The front desks subtended an angle
of 50.2 to the mic array, and the drummer lay within that angle. So it seems
unlikely that the drummer's wide positioning contributed to the perceived weird
imaging.

I can't listen with any Dolby surround set-up, but I'd first suspect the dismal
room geometry and reflections as the main culprit for any imaging anomalies
(Fig8's might actually have helped here against that the low ceiling?) Actually,
I didn't find the image shifting very distracting...and thought Gary did a
pretty credible job, considering the tools he had and the hall he had to contend
with.

But wow, those heavy mics supported by that lone, dinky stand-base
thread!...that does make me shiver. Also, those Fig8 mics may be vulnerable to
stand-borne resonances. And perhaps consider relocating the bass amp, not the
player, to a more central position?
  #44   Report Post  
Posted to rec.audio.pro
Scott Dorsey Scott Dorsey is offline
external usenet poster
 
Posts: 16,853
Default Fascinating MS

Gary Eickmeier wrote:
"Scott Dorsey" wrote in message
...
Gary Eickmeier wrote:
A possible new problem has come up with MS, namely some imaging anomalies
at
different frequencies. When I do my stereo test and even during a
performance, I have noticed that higher frequency percussive sounds will
image in the center more than at left or right. Like, the drum set is at
stage left, but there are some pings and other sounds that come from the
center.

Is this some well known principle, or fault, of MS? Ever heard of it?


It's a room problem. Move the mike.


Great responses - thanks to all. I will try some of the tests you suggest.
Could well be a mike problem, changing the M to S ratio with frequency.


You're using two identical mikes, so the response should be the same,
right? It's true that if the side mike has poor high frequency response
off-axis, or is just soft on top, that high frequency things will collapse
into the center of the soundfield. I experienced this with a 77DX
combined with an omni condenser, back when I was a student.

But I'm inclined to think you have reflection issues in your room.

Don't know what the test results might be, but all I can tell you is that I
am using the Audio Technica 2050 variable pattern mikes in Fig 8 pattern.
These are reasonable quality for a beginner like me and I would expect that
would work reasonably well, and maybe my MS mix isn't quite perfiect yet.
And BTW the same phenomenon holds true looking at the lissajous pattern, or
phase response window in Audition, so it is a recording problem and not so
much playback - but I do realize how the rear speakers can affect perceived
frontal direction as well so I will do more testing in stereo only.


Measure it and see. Set up the mike outside, start recording, then walk
a circle around the microphone jingling a set of keys and calling out where
you are. If the high frequency response varies with position, you'll be
able to tell it from just a drop in amplitude overall.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
  #45   Report Post  
Posted to rec.audio.pro
Gary Eickmeier Gary Eickmeier is offline
external usenet poster
 
Posts: 1,449
Default Fascinating MS


"Tom McCreadie" wrote in message
...
John Williamson wrote:

You could try altering the EQ on the S channel to alter the relative
levels of the HF percussion. If it moves in and out, you've got a
frequency response problem.

But altering the HF equalization on the S channel - or the M channel, for
that
matter - will _always_ make the imaging of HF components move in or out.
That's
pure physics, and such a phenomenon would also occur with perfect mics, so
one
can't use such an experimental outcome to draw a conclusion on Gary's
case.

His AT mics may well have an uneven off-axis response, but he was
employing two
fig8 mics, so if the AT manufacturing process results mainly in a
systematic-
rather than random frequency response skew in the mic patterns, there may
be a
fortuitous "close-tolerance unevenness-matching" :-) between M and S
mics, that
would provide a mitigating effect.


The drummer was actually pretty close to halfway between the M and S
patterns, so if it was off axis it was probably the same for both. But on
the stereo call out test I first noticed this, my voice would go where it
belonged but the clicks on my rosewood sticks would go toward the center
more.

An ideal Fig8 MS with -3dB S gain equates mathematically to a Fig8 XY pair
splayed at 35.3. That would have a Sengpiel SRA of 47.7 (with the
ambiophonic region beginning beyond 54.7). The front desks subtended an
angle
of 50.2 to the mic array, and the drummer lay within that angle. So it
seems
unlikely that the drummer's wide positioning contributed to the perceived
weird
imaging.


This agrees pretty much with what I am hearing in playback. The extreme
channel material is in the Dolby zone kind of beyond the left or right
walls. I am now using S as 6 dB down for that reason. This varies with each
session I suppose, depending on how perfectly I balance the channels during
recording. The indicated knob position is not accurate. I just balance the
channels on recording, then take care of the M to S ratio during post.

I can't listen with any Dolby surround set-up, but I'd first suspect the
dismal
room geometry and reflections as the main culprit for any imaging
anomalies
(Fig8's might actually have helped here against that the low ceiling?)
Actually,
I didn't find the image shifting very distracting...and thought Gary did a
pretty credible job, considering the tools he had and the hall he had to
contend
with.

But wow, those heavy mics supported by that lone, dinky stand-base
thread!...that does make me shiver. Also, those Fig8 mics may be
vulnerable to
stand-borne resonances. And perhaps consider relocating the bass amp, not
the
player, to a more central position?


Oh, believe me, some additional training will be required for him. He can't
hear his levels very well, so between tracks he turns it down, and for each
track he turns it all the way up again. I am going to have to try some
stealth training to get him to put a mark on the knob and set it by eye to a
reasonable level.

On the mike stand, you may be right. Here is a better shot of the MS
bracket:

https://s3.amazonaws.com/masters.gal...cac6a5ae4547c4

https://s3.amazonaws.com/masters.gal...0bd5296857c590

I know, I know, TinyURL but I haven't got time to mess with it.

I have been looking for a one piece MS microphone but not impressed with the
reviews on them or the prices. Maybe e-bay could help.

Gary







  #46   Report Post  
Posted to rec.audio.pro
Gary Eickmeier Gary Eickmeier is offline
external usenet poster
 
Posts: 1,449
Default Fascinating MS

I'm not sure you can hear what I am talking about in a soundcloud file, but
what the hell:

https://soundcloud.com/eickmeier-1/stereo-test-4wav

https://soundcloud.com/eickmeier-1/s...the-savoy-4wav

Gary


  #47   Report Post  
Posted to rec.audio.pro
Luxey Luxey is offline
external usenet poster
 
Posts: 617
Default Fascinating MS

недеља, 15. фебруар 2015. 07.18.11 UTC+1, Gary Eickmeier је написао/ла:
This agrees pretty much with what I am hearing in playback. The extreme
channel material is in the Dolby zone kind of beyond the left or right
walls. I am now using S as 6 dB down ...


Well, turn it up!

Also, for a check, stick your head where the mic setup is and haave someone els hit the sticks arround. What do you hear?

Again, with setup as is, and levels as they are, I suggest turning whole setup 60 degrees clockwise.
  #48   Report Post  
Posted to rec.audio.pro
Gary Eickmeier Gary Eickmeier is offline
external usenet poster
 
Posts: 1,449
Default Fascinating MS

Luxey wrote:
??????, 15. ??????? 2015. 07.18.11 UTC+1, Gary Eickmeier ??
???????/??:
This agrees pretty much with what I am hearing in playback. The
extreme channel material is in the Dolby zone kind of beyond the
left or right walls. I am now using S as 6 dB down ...


Well, turn it up!

Also, for a check, stick your head where the mic setup is and haave
someone els hit the sticks arround. What do you hear?

Again, with setup as is, and levels as they are, I suggest turning
whole setup 60 degrees clockwise.


You keep saying that - what's up with that?

I have done a few experiments outdoors - will report later when it isn't so
late.

Gary


  #49   Report Post  
Posted to rec.audio.pro
Tom McCreadie Tom McCreadie is offline
external usenet poster
 
Posts: 205
Default Fascinating MS

Gary Eickmeier wrote:

"Tom McCreadie" wrote in message
.. .


But wow, those heavy mics supported by that lone, dinky stand-base
thread!...that does make me shiver. Also, those Fig8 mics may be
vulnerable to stand-borne resonances.


On the mike stand, you may be right. Here is a better shot of the MS
bracket:

https://s3.amazonaws.com/masters.gal...cac6a5ae4547c4

https://s3.amazonaws.com/masters.gal...0bd5296857c590

I know, I know, TinyURL but I haven't got time to mess with it.


Those two links gave me an "Access denied... Message has expired"

To clarify, though, my comment wasn't on the mic holder arrangement, but rather
about the central pole (with its heavy attachments) only being connected to the
stand base by means of a single, flimsy screw thread. I'd be nervous about the
stand swaying, resonating, capsizing or snapping off.
--
Tom McCreadie
  #50   Report Post  
Posted to rec.audio.pro
Luxey Luxey is offline
external usenet poster
 
Posts: 617
Default Fascinating MS

понедељак, 16. фебруар 2015. 09.07.06 UTC+1, Gary Eickmeier је написао/ла:
You keep saying that - what's up with that?


Almost everyone told you to move the microphones, I also said so, in a form of
which way to do so.

I have done a few experiments outdoors - will report later when it isn't so
late.


What's the point of eperimenting outside? To her the setup without reflections?
Thaat may give you an idea, or a clue, but the point is, you can not set and
forget yor microphones based on some idea, you have to listen and adapt as per
given space and situation.


  #51   Report Post  
Posted to rec.audio.pro
Gary Eickmeier Gary Eickmeier is offline
external usenet poster
 
Posts: 1,449
Default Fascinating MS


"hank alrich" wrote in message
...
Luxey wrote:

?????????, 16. ??????? 2015. 09.07.06 UTC+1, Gary Eickmeier ??
???????/??:
You keep saying that - what's up with that?


Almost everyone told you to move the microphones, I also said so, in a
form of
which way to do so.

I have done a few experiments outdoors - will report later when it
isn't so
late.


What's the point of eperimenting outside? To her the setup without
reflections? Thaat may give you an idea, or a clue, but the point is, you
can not set and forget yor microphones based on some idea, you have to
listen and adapt as per given space and situation.


This is a critical point. Monitoring.


"Move the microphones" - I set up my microphones to record single point
stereo with the perspective that I want to hear on the recording. You don't
move them to a bad perspective for some sonic problem. I would think you
solve the problem. Of course if it were a recording session, you could move
the entire band to someplace that didn't have the problem, but Lux is
telling me to turn the mikes 60 degrees to the right and have the
perspective of a band in the left channel and nothing in the right. I don't
know if he is punking me or what.

Monitoring - yes, sure, you never shoot or record without monitoring the
sound, but I am recording in MS RAW, which is not real helpful for telling
how the stereo is going.

And there are some real surprising - even humorous - anomolies happening
with a pair of Fig 8 mikes after decoding to stereo that I will show and
tell about when I get time to post my results of testing outdoors.

Gary


  #52   Report Post  
Posted to rec.audio.pro
Gary Eickmeier Gary Eickmeier is offline
external usenet poster
 
Posts: 1,449
Default Fascinating MS


"Tom McCreadie" wrote in message
...
Gary Eickmeier wrote:


I know, I know, TinyURL but I haven't got time to mess with it.


Those two links gave me an "Access denied... Message has expired"

To clarify, though, my comment wasn't on the mic holder arrangement, but
rather
about the central pole (with its heavy attachments) only being connected
to the
stand base by means of a single, flimsy screw thread. I'd be nervous
about the
stand swaying, resonating, capsizing or snapping off.
--
Tom McCreadie


Hmmm - I thought I tested those links after I sent them. Sorry about that.

This is not my main mike stand, just easier to carry and put up since my
back surgery. Seems to be plenty sturdy.

Gary


  #53   Report Post  
Posted to rec.audio.pro
Scott Dorsey Scott Dorsey is offline
external usenet poster
 
Posts: 16,853
Default Fascinating MS

Gary Eickmeier wrote:

"Move the microphones" - I set up my microphones to record single point
stereo with the perspective that I want to hear on the recording. You don't
move them to a bad perspective for some sonic problem.


There are lots of places with a good perspective. One of them might be
six inches away from where you are now. Stick your finger in your ear,
listen with one ear, move your head around and see.

When you come across a standing wave problem at high frequencies or a
flutter echo, you'll hear it very easily with one ear and you might not
notice it so easily with both.

I would think you
solve the problem. Of course if it were a recording session, you could move
the entire band to someplace that didn't have the problem, but Lux is
telling me to turn the mikes 60 degrees to the right and have the
perspective of a band in the left channel and nothing in the right. I don't
know if he is punking me or what.


No, that's not what he's telling you, I don't believe.

Monitoring - yes, sure, you never shoot or record without monitoring the
sound, but I am recording in MS RAW, which is not real helpful for telling
how the stereo is going.


So, basically you have no real monitoring in the field, which is really
much of your problem. It's possible to work this way but it's a whole lot
more difficult and you have to leave a lot to chance.

And there are some real surprising - even humorous - anomolies happening
with a pair of Fig 8 mikes after decoding to stereo that I will show and
tell about when I get time to post my results of testing outdoors.


My suspicion is that what you're encountering are normal room problems.
It goes with the territory.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."
  #54   Report Post  
Posted to rec.audio.pro
Luxey Luxey is offline
external usenet poster
 
Posts: 617
Default Fascinating MS

понедељак, 16. фебруар 2015. 21.53.33 UTC+1, Gary Eickmeier је написао/ла:
is a critical point. Monitoring.

"Move the microphones" - I set up my microphones to record single point
stereo with the perspective that I want to hear on the recording.


Pardone moi, but I thought you did not like what you heard on that recording, just like I did not. If you liked it and that is what you were after, then why are we even talking about it? Listen aand enjoy!
  #55   Report Post  
Posted to rec.audio.pro
Gary Eickmeier Gary Eickmeier is offline
external usenet poster
 
Posts: 1,449
Default Fascinating MS


"Scott Dorsey" wrote in message
...

Measure it and see. Set up the mike outside, start recording, then walk
a circle around the microphone jingling a set of keys and calling out
where
you are. If the high frequency response varies with position, you'll be
able to tell it from just a drop in amplitude overall.
--scott


I took the stereo pair outside and did it in stereo in several mike patterns
but now I see you are saying to do it with just one mike and check the roll
off. But I am afraid my keys are not jingly enough to I got my sticks out
again for click tests all around.

Stay tuned, maybe on a new thread. I am getting less and less fascinated
with MS.

Gary




  #56   Report Post  
Posted to rec.audio.pro
Frank Stearns Frank Stearns is offline
external usenet poster
 
Posts: 1,134
Default Fascinating MS

"Gary Eickmeier" writes:


snips

The problem I have discovered is from the miking technique (MS) rather than
the mikes or moving the mikes or my perspective. I will demonstrate as soon
as I can upload some files, but the idea is the Fig 8 pattern that I have
been using has a channel reversal in the rear and some strange left channel
problems that are probably associated with that and the decoding process.


Yes, there are limits to MS, as I've noted before. What do you think you've
discovered?

BTW, forgot to mention earlier as a possible source of irritation when doing MS: By
no means are all figure 8 microphones created equally. Polar response -- and even
the actual output volume -- might be different between the front and rear lobes of
the same fig 8 mic! (In fact, with some of the Royer ribbons, the company warns
about a different output level between front and rear.)

Thus, it's bad enough when the response between the M and S microphones are off
(either due to different mic types or due to poor off-axis response of the S mic
even if the same model as M), but then you discover issues with an asymmetrical
response between S+ and S-!

Ouch.

About the only way I'd go back to MS would be with the Schoeps or Neumann MS rigs --
both (IRCC) well north of US$5000 by the time you got done. I can get a better sound
for well less than half that investment using omnis.

Interestingly, the advanced (or maybe it was a 3rd party custom) Schoeps MS rig at
one time included a third mic -- an omni -- to compensate for the overall
less-than-adequate LF response of the directional microphones used for the main M-S.
They even included some sort of crossover network to blend the LF omni with the mid,
if I remember correctly. That rig was very expensive.)

Frank
Mobile Audio

--
  #57   Report Post  
Posted to rec.audio.pro
None None is offline
external usenet poster
 
Posts: 782
Default Fascinating MS

"Gary Eickmeier" wrote in message
...
... the Fig 8 pattern that I have been using has a channel reversal
in the rear and some strange left channel problems that are probably
associated with that and the decoding process.


LOL! Your figure eight microphone has "channel reversal in the rear."
An astounding discovery! Did you expect otherwise?

  #58   Report Post  
Posted to rec.audio.pro
hank alrich hank alrich is offline
external usenet poster
 
Posts: 4,736
Default Fascinating MS

Gary Eickmeier wrote:

"Scott Dorsey" wrote in message
...

Measure it and see. Set up the mike outside, start recording, then walk
a circle around the microphone jingling a set of keys and calling out
where
you are. If the high frequency response varies with position, you'll be
able to tell it from just a drop in amplitude overall.
--scott


I took the stereo pair outside and did it in stereo in several mike patterns
but now I see you are saying to do it with just one mike and check the roll
off. But I am afraid my keys are not jingly enough to I got my sticks out
again for click tests all around.

Stay tuned, maybe on a new thread. I am getting less and less fascinated
with MS.

Gary


Gary, the combo of your inexpesnive kit, your lack of understanding, and
your "monitoring" makes for quite a sonic party. Your opinions of what
is what will not hold past a certain point, because frankly in some
areas they border on delusional. Please step back from them and at least
_try_ to get your head around many things that have been told you here.

MS works terrificly well when well implemented. Imagine that. Accept
that. Then stop blaming the mic configuration and start listening. If
you give Scott that same rig in the same room with the same sources you
will be startled at the result. In fact, hiring him to come consult on
even a single recording might be a wise approach to this, as so much of
what is needed is education.

--
shut up and play your guitar * HankAlrich.Com
HankandShaidriMusic.Com
YouTube.Com/WalkinayMusic
  #59   Report Post  
Posted to rec.audio.pro
hank alrich hank alrich is offline
external usenet poster
 
Posts: 4,736
Default Fascinating MS

Frank Stearns wrote:

About the only way I'd go back to MS would be with the Schoeps or Neumann
MS rigs -- both (IRCC) well north of US$5000 by the time you got done. I
can get a better sound for well less than half that investment using
omnis.


Josephson C700S.

--
shut up and play your guitar * HankAlrich.Com
HankandShaidriMusic.Com
YouTube.Com/WalkinayMusic
  #61   Report Post  
Posted to rec.audio.pro
Scott Dorsey Scott Dorsey is offline
external usenet poster
 
Posts: 16,853
Default Fascinating MS

Frank Stearns wrote:
(hank alrich) writes:

Frank Stearns wrote:


About the only way I'd go back to MS would be with the Schoeps or Neumann
MS rigs -- both (IRCC) well north of US$5000 by the time you got done. I
can get a better sound for well less than half that investment using
omnis.


Josephson C700S.


Nice. Spendy. Nice and Spendy. But, knowing Mr. Josephson, worth every penny.


I don't know. If I had that kind of money, I think I'd sooner go with a
pair of Josephson C617 omnis, assuming I had good rooms to work with. But
then again, you don't always have good rooms to work with. And sometimes
you have a customer who is obsessed with mono compatibility.
--scott


--
"C'est un Nagra. C'est suisse, et tres, tres precis."
  #62   Report Post  
Posted to rec.audio.pro
hank alrich hank alrich is offline
external usenet poster
 
Posts: 4,736
Default Fascinating MS

Scott Dorsey wrote:

Frank Stearns wrote:
(hank alrich) writes:

Frank Stearns wrote:


About the only way I'd go back to MS would be with the Schoeps or Neumann
MS rigs -- both (IRCC) well north of US$5000 by the time you got done. I
can get a better sound for well less than half that investment using
omnis.


Josephson C700S.


Nice. Spendy. Nice and Spendy. But, knowing Mr. Josephson, worth
every penny.


I don't know. If I had that kind of money, I think I'd sooner go with a
pair of Josephson C617 omnis, assuming I had good rooms to work with. But
then again, you don't always have good rooms to work with. And sometimes
you have a customer who is obsessed with mono compatibility.
--scott


I have only read one report from an engineer who used it. He said it was
"holographic".

--
shut up and play your guitar * HankAlrich.Com
HankandShaidriMusic.Com
YouTube.Com/WalkinayMusic
  #63   Report Post  
Posted to rec.audio.pro
Tom McCreadie Tom McCreadie is offline
external usenet poster
 
Posts: 205
Default Fascinating MS

Gary, I'm not really familiar with the details of your surround sound
shenanigans, but the following applies to straight two-channel stereo:

You will _always_ get an image lateral-inversion (your "channel reversal") of
certain rear-arriving sounds whenever you employ:
1. an XY array (except 180 back-to-back splayed) with mics of tighter pattern
than cardioid
or
2. an MS system that after decoding equates to the above array "1"

Why is this? The mic patterns in the above arrays always have a rear lobe of
negative polarity. And there will always exist some angular direction within the
rear right quadrant w.r.t. the array from which an arriving sound will deliver a
stronger mic signal via the negative lobe of the L-angled mic than via the
negative lobe of the R-angled sister mic.

Consider, for illustration, the classic 45 Blumlein. The axis of the rear
lobe of the L-angled mic (and the null of the R-angled mic) points to "4:30
o'clock". So a sound arriving from, say, 4:45 o'clock would deliver a strong
signal (albeit negative) into the L-channel, but a much wimpier signal (though
also negative) into the R-channel. Hence a sound source located at 4:45 o'clock
will image left of centre on two-speaker playback, i.e. as if it were located at
7:15 o'clock, i.e. lateral-inversion of image.

The actual angular width of this lateral-inversion rear sector varies with the
mic pattern, XY splay angle and M:S ratio....but there's never a
lateral-inversion when using omni in MS because an omni records all signals with
positive phase.

---
This email has been checked for viruses by Avast antivirus software.
http://www.avast.com

  #64   Report Post  
Posted to rec.audio.pro
Gary Eickmeier Gary Eickmeier is offline
external usenet poster
 
Posts: 1,449
Default Fascinating MS


"Tom McCreadie" wrote in message
...
Gary, I'm not really familiar with the details of your surround sound
shenanigans, but the following applies to straight two-channel stereo:

You will _always_ get an image lateral-inversion (your "channel
reversal") of
certain rear-arriving sounds whenever you employ:
1. an XY array (except 180 back-to-back splayed) with mics of tighter
pattern
than cardioid
or
2. an MS system that after decoding equates to the above array "1"

Why is this? The mic patterns in the above arrays always have a rear lobe
of
negative polarity. And there will always exist some angular direction
within the
rear right quadrant w.r.t. the array from which an arriving sound will
deliver a
stronger mic signal via the negative lobe of the L-angled mic than via the
negative lobe of the R-angled sister mic.

Consider, for illustration, the classic 45 Blumlein. The axis of the
rear
lobe of the L-angled mic (and the null of the R-angled mic) points to
"4:30
o'clock". So a sound arriving from, say, 4:45 o'clock would deliver a
strong
signal (albeit negative) into the L-channel, but a much wimpier signal
(though
also negative) into the R-channel. Hence a sound source located at 4:45
o'clock
will image left of centre on two-speaker playback, i.e. as if it were
located at
7:15 o'clock, i.e. lateral-inversion of image.

The actual angular width of this lateral-inversion rear sector varies with
the
mic pattern, XY splay angle and M:S ratio....but there's never a
lateral-inversion when using omni in MS because an omni records all
signals with
positive phase.


Yes, that is what my experiment confirmed, as expected. I just needed to
hear it for myself in an anechoic experiment and on my system.

Gary


  #65   Report Post  
Posted to rec.audio.pro
[email protected] sv477445@gmail.com is offline
external usenet poster
 
Posts: 1
Default Fascinating MS

amar


Reply
Thread Tools
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Fascinating tour of Kudelski/Nagra Peter Larsen[_3_] Pro Audio 0 April 3rd 10 08:23 AM
NYOBs fascinating find [email protected] Audio Opinions 24 October 21st 05 11:22 AM
An ever-fascinating subject: Quad II Andre Jute Vacuum Tubes 5 December 10th 04 12:32 AM
See the Most Fascinating Music System on the Market... WENW Marketplace 8 April 17th 04 08:56 AM
See the Most Fascinating Music System on the Market... WENW Marketplace 0 April 16th 04 12:47 AM


All times are GMT +1. The time now is 11:17 AM.

Powered by: vBulletin
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright 2004-2024 AudioBanter.com.
The comments are property of their posters.
 

About Us

"It's about Audio and hi-fi"