X-Git-Url: http://shamusworld.gotdns.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=_manual%2F17_mixing%2F02_panning%2F03_stereo_panner.html;h=c25feb7cd3d871270c14595677b93b48c56df32a;hb=25ceb163cbcd98fe9c6a28fa13985368e33bed0f;hp=979578336c8e3a378692f440daae3ab7935e5c82;hpb=19ee4b8d24f3de68b19a597734d919053ef6491a;p=ardour-manual-diverged diff --git a/_manual/17_mixing/02_panning/03_stereo_panner.html b/_manual/17_mixing/02_panning/03_stereo_panner.html index 9795783..c25feb7 100644 --- a/_manual/17_mixing/02_panning/03_stereo_panner.html +++ b/_manual/17_mixing/02_panning/03_stereo_panner.html @@ -4,29 +4,28 @@ title: Stereo Panner ---

- The default stereo panner distributes two inputs to two outputs. Its - behaviour is controlled by two parameters, width and - position. The - default settings for the stereo panner are width=100% and - position=center. - This stereo panner assumes that the signals + The default stereo panner distributes two inputs to two outputs. Its + behaviour is controlled by two parameters, width and + position. By default, the panner is centered at full width. +

+

+ The stereo panner assumes that the signals you wish to distribute are either uncorrelated (i.e. totally independent), or that they contain a stereo image which is - mono-compatible, such as a co-incident microphone recording, or a + mono-compatible, such as a co-incident microphone recording, or a sound stage that has been created with pan pots.*

-
+

With the default values it is not possible to alter the position, since the width is already spread entirely across both outputs. To alter the position, you must first reduce the width. -

+

Stereo Panner User Interface

-

- The panner user interface consists of three elements, divided between + The panner user interface consists of three elements, divided between the top and bottom half. Click and/or drag in the top half to control position; click and/or drag in the bottom half to control width (see below for details). @@ -56,8 +55,8 @@ title: Stereo Panner

Although the implementation of the panner uses the "position" - parameter, when the user interface displays it numerically, it shows a pair of numbers that - will be familiar to most audio engineers. + parameter, when the user interface displays it numerically, it shows + a pair of numbers that will be familiar to most audio engineers.

@@ -106,47 +105,47 @@ title: Stereo Panner To change the position smoothly, press the right button and drag within the top half of the panner, then release. The position will be limited by the current width setting. Note: you do not need - to grab the position indicator in order to drag + to grab the position indicator in order to drag.

To change the width smoothly, press the right button and drag within the lower half of the panner, then release. The width will be - limited by the current position setting.Note: you do not need to - grab the L/R indicators in order to drag + limited by the current position setting. Note: you do not need to + grab the L/R indicators in order to drag.

Reset to defaults
-
Click right button
+
Click right
-
Change to a "hard left"
-
Double click right button in the upper left half +
Change to hard left
+
Double click right in the upper left half of the panner
-
Change to a "hard right"
-
Double click right button in the upper right half +
Change to a hard right
+
Double click right in the upper right half of the panner
Move position as far left as possible, given width
-
Double click right button in the upper left half of the +
Double click right in the upper left half of the panner
Move position as far right as possible, given width
-
Double click right button in the upper right half of the +
Double click right in the upper right half of the panner
Set the position to center
-
Click right button in the upper middle of the panner
+
Click right in the upper middle of the panner
Reset to maximum possible width
-
Double click right button on the lower left side
+
Double click right on the lower left side
Invert (flip channel assignments)
-
Double click right button on the lower right side
+
Double click right on the lower right side
Set width to 0°
-
Double click right button in the lower middle
+
Double click right in the lower middle

Keyboard bindings

@@ -179,34 +178,31 @@ title: Stereo Panner

-
left / left
-
increase width by 1° / 5°
- -
right / right
-
decrease width by 1° / 5°
- -
up / up
-
move position 1° / 5° to the left
- -
down / down
-
move position 1° / 5°to the right
+
⇐ / ⇐
+
increase width by 1° / 5°
+
⇒ / ⇒
+
decrease width by 1° / 5°
+
⇑ / ⇑
+
move position 1° / 5° to the left
+
⇓ / ⇓
+
move position 1° / 5°to the right

Stereo panning caveats

-
+

The stereo panner will introduce unwanted side effects on material that includes a time difference between the channels, such as A/B, ORTF or NOS microphone recordings, or delay-panned mixes.
When you reduce the with, you are effectively summing two highly -correlated signals with a delay, which will cause comb filtering. -

+correlated signals with a delay, which will cause comb filtering. +

Let's take a closer look at what happens when you record a source at 45° to the right side with an ORTF stereo microphone array and then manipulate the width.

-For testing, we apply a pink noise signal to both inputs of an Ardour stereo +For testing, we apply a pink noise signal to both inputs of an Ardour stereo bus with the stereo panner, and feed the bus output to a two-channel analyser. Since pink noise contains equal energy per octave, the expected readout is a straight line, which would indicate that our signal chain does not color the @@ -220,7 +216,7 @@ control LV2 to set the level difference and time delay. Ignore the Trim/Gain analyser.

-Recall that an ORTF microphone pair consists of two cardioids spaced 17 cm +Recall that an ORTF microphone pair consists of two cardioids spaced 17 cm apart, with an opening angle of 110°. For a far source at 45° to the right, the time difference between the capsules is 350 μs or approximately 15 samples at 44.1 kHz. The level difference @@ -243,10 +239,11 @@ inside your signal chain, this spatial separation is lost and the brain will no longer be able to sort out the timbral mess. As usual, you get to keep the pieces.

-
+

Depending on your material and on how much you need to manipulate the width, some degree of comb filtering may be acceptable. Then again, it may not. Listen carefully for artefacts if you manipulate unknown stereo signals — many orchestra sample libraries for example do contain time-delay components. -

+

+