Mouse operations in the upper half of the panner adjust the position
- parameter, constrained by the current width setting.
+ parameter, constrained by the current width setting.
Mouse operations in the lower half of the panner adjust the width
- parameter, constrained by the current position setting.
+ parameter, constrained by the current position setting.
To change the position smoothly, press the right button and drag
@@ -110,39 +116,39 @@
grab the L/R indicators in order to drag.
-
+
-- Reset to defaults
-- Click right
+| Reset to defaults |
+Click right |
|---|
-- Change to hard left
-- Double click right in the upper left half
- of the panner
+| Change to hard left |
+Double click right in the upper left half
+ of the panner |
|---|
-- Change to a hard right
-- Double click right in the upper right half
- of the panner
+| 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 in the upper left half of the
- panner
+| Move position as far left as possible, given width |
+Double click right in the upper left half of the
+ panner |
|---|
-- Move position as far right as possible, given width
-- Double click right in the upper right half of the
- panner
+| Move position as far right as possible, given width |
+Double click right in the upper right half of the
+ panner |
|---|
-- Set the position to center
-- Click right in the upper middle of the panner
+| Set the position to center |
+Click right in the upper middle of the panner |
|---|
-- Reset to maximum possible width
-- Double click right on the lower left side
+| Reset to maximum possible width |
+Double click right on the lower left side |
|---|
-- Invert (flip channel assignments)
-- Double click right on the lower right side
+| Invert (flip channel assignments) |
+Double click right on the lower right side |
|---|
-- Set width to 0°
-- Double click right in the lower middle
-
+| Set width to 0° |
+Double click right in the lower middle |
|---|
+
Keyboard bindings
@@ -151,20 +157,20 @@
keybindings are available to operate on that panner:
-
- - ↑ / ↑
- - increase width by 1° / 5°
- - ↓ / ↓
- - decrease width by 1° / 5°
- - ← / ←
- - move position 1° / 5° to the left
- - → / →
- - move position 1° / 5° to the right
- - 0
- - reset position to center
- - ↑
- - reset width to full (100%)
-
+
+ | ↑ / ↑ |
+ increase width by 1° / 5° |
|---|
+ | ↓ / ↓ |
+ decrease width by 1° / 5° |
|---|
+ | ← / ← |
+ move position 1° / 5° to the left |
|---|
+ | → / → |
+ move position 1° / 5° to the right |
|---|
+ | 0 |
+ reset position to center |
|---|
+ | ↑ |
+ reset width to full (100%) |
|---|
+
Using the scroll wheel/touch scroll
@@ -173,50 +179,50 @@
wheel may be used as follows:
-
- - ⇐ / ⇐
- - increase width by 1° / 5°
- - ⇒ / ⇒
- - decrease width by 1° / 5°
- - ⇑ / ⇑
- - move position 1° / 5° to the left
- - ⇓ / ⇓
- - 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.
+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.
-
+
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
-bus with the stereo panner, and feed the bus output to a two-channel analyser.
+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
sound:
+
+
-To simulate an ORTF, we use Robin Gareus' stereo balance
-control LV2 to set the level difference and time delay. Ignore the Trim/Gain
-— its purpose is just to align the test signal with the 0dB line of the
-analyser.
+ To simulate an ORTF, we use Robin Gareus' stereo balance control LV2 to set the level difference and time delay. Ignore the Trim/Gain—its purpose is just to align the test signal with the 0dB line of the analyser.
-
+
+
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
-due to the directivity of the microphones is about 7.5 dB (indicated by the
+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
+due to the directivity of the microphones is about 7.5 dB (indicated by the
distance between the blue and red lines in the analyser).
@@ -226,7 +232,7 @@ happens to the frequency response of the left and right outputs:
-You may argue that all spaced microphone recordings will undergo comb
+You may argue that all spaced microphone recordings will undergo comb
filtering later, when the two channels recombine in the air between the speakers.
Perceptually however, there is a huge of difference: our hearing system is
very good at eliminating comb filters in the real world, where their component
@@ -238,9 +244,6 @@ 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
+carefully for artefacts if you manipulate unknown stereo signals—many
orchestra sample libraries for example do contain time-delay components.
-
-
-
+ 
+