Problem with audio clipping - Revision history

Akw at 10:15, 22 November 2013

2013-11-22T10:15:44Z

2013-11-22T10:12:35Z

2007-11-17T04:53:10Z

‎Model-specific observations

2007-11-16T03:22:57Z

‎Model-specific observations

2007-11-15T23:04:49Z

‎Model-specific observations

2007-11-15T23:01:56Z

‎Model-specific observations

2007-08-27T08:13:52Z

2007-06-15T11:13:30Z

‎Model-specific observations

2007-06-15T09:51:21Z

‎Model-specific observations

2007-06-15T09:49:27Z

‎Model-specific observations

@@ Line 4: / Line 4: @@
 '''Solution:''' Reduce the volume on the responsible mixer channel(s).
-e.g. in the console ''alsamixer'' with control via arrows: up/down left/right.
+e.g. in the console ''alsamixer'' with control via arrows: {{ibmkey|↑|#494949}} / {{ibmkey|↓|#494949}} and {{ibmkey|←|#494949}} / {{ibmkey|→|#494949}}.
 ===Model-specific observations===

@@ Line 3: / Line 3: @@
 This is caused by a hardware flaw: excessive internal amplification saturates the audio channels, resulting in [http://en.wikipedia.org/wiki/Clipping_(audio) clipping].
-Solution: reduce the volume on the responsible mixer channel(s).
+'''Solution:''' Reduce the volume on the responsible mixer channel(s).
 e.g. in the console ''alsamixer'' with control via arrows: up/down left/right.

@@ Line 13: / Line 13: @@
 * {{R51e}} ([[AD1981B]] audio controller): PCM channel volume higher than 84% may result in clipping, regardless of the Master channel.
 * {{Z61e}} (Intel High Definition with AD1981): Just turn down the PCM channel volume to at least 77% and you should be happy (in some combination with external speakers, 65% was needed), the Master Channel can be kept at 100%. If that doesn't help, loading snd-hda-intel with model=thinkpad and position_fix=1 might also improve a bit.
-* {{X30}} ([[AD1981A]]), {{X31}} ([[AD1981B]]), {{X32}} ([[AD1981B]]): volume gain from alsamixer (gain for Line, CD, Mic, Phone, and Aux is identical as PCM)
+* ([[AD1981A]]) {{X30}}, ([[AD1981B]]) {{X31}}, {{X32}}, {{X41_Tablet}}: volume gain from alsamixer (gain for Master Mono and Headphone is identical as Master, gain for Line, CD, Mic, Phone, and Aux is identical as PCM)
 ** Master 100% == 0dB
 ** PCM 74% == 0dB
 ** PCM 100% == +12dB

@@ Line 13: / Line 13: @@
 * {{R51e}} ([[AD1981B]] audio controller): PCM channel volume higher than 84% may result in clipping, regardless of the Master channel.
 * {{Z61e}} (Intel High Definition with AD1981): Just turn down the PCM channel volume to at least 77% and you should be happy (in some combination with external speakers, 65% was needed), the Master Channel can be kept at 100%. If that doesn't help, loading snd-hda-intel with model=thinkpad and position_fix=1 might also improve a bit.
-* {{X32}} ([[AD1981B]]) volume gain from alsamixer (gain for Line, CD, Mic, Phone, and Aux is identical as PCM)
+* {{X30}} ([[AD1981A]]), {{X31}} ([[AD1981B]]), {{X32}} ([[AD1981B]]): volume gain from alsamixer (gain for Line, CD, Mic, Phone, and Aux is identical as PCM)
 ** Master 100% == 0dB
 ** PCM 74% == 0dB
 ** PCM 100% == +12dB

@@ Line 13: / Line 13: @@
 * {{R51e}} ([[AD1981B]] audio controller): PCM channel volume higher than 84% may result in clipping, regardless of the Master channel.
 * {{Z61e}} (Intel High Definition with AD1981): Just turn down the PCM channel volume to at least 77% and you should be happy (in some combination with external speakers, 65% was needed), the Master Channel can be kept at 100%. If that doesn't help, loading snd-hda-intel with model=thinkpad and position_fix=1 might also improve a bit.
-* {{X32}} volume gain from alsamixer (gain for Line, CD, Mic, Phone, and Aux is identical as PCM)
+* {{X32}} ([[AD1981B]]) volume gain from alsamixer (gain for Line, CD, Mic, Phone, and Aux is identical as PCM)
 ** Master 100% == 0dB
 ** PCM 74% == 0dB
 ** PCM 100% == +12dB

@@ Line 7: / Line 7: @@
 ===Model-specific observations===
-* ThinkPad {{T43}} ([[AD1981B]] audio controller): PCM channel volume higher than 70% may result in clipping, regardless of the Master channel.
+(you can use alsamixer panel to find out if setting to 100% amplifies anything)
-* ThinkPad {{R40}}  (Intel 82801DB/DBL/DBM audio controller (AC97)): PCM volume needs to be set under 80%, higher values cause clipping. Same with the Master channel as on T43.
-* ThinkPad {{R51e}} ([[AD1981B]] audio controller): PCM channel volume higher than 84% may result in clipping, regardless of the Master channel.
+* {{T43}} ([[AD1981B]] audio controller): PCM channel volume higher than 70% may result in clipping, regardless of the Master channel.
-* ThinkPad {{Z61e}} (Intel High Definition with AD1981): Just turn down the PCM channel volume to at least 77% and you should be happy (in some combination with external speakers, 65% was needed), the Master Channel can be kept at 100%. If that doesn't help, loading snd-hda-intel with model=thinkpad and position_fix=1 might also improve a bit.
+* {{R40}}  (Intel 82801DB/DBL/DBM audio controller (AC97)): PCM volume needs to be set under 80%, higher values cause clipping. Same with the Master channel as on T43.

@@ Line 9: / Line 9: @@
 * ThinkPad {{T43}} ([[AD1981B]] audio controller): PCM channel volume higher than 70% may result in clipping, regardless of the Master channel.
 * ThinkPad {{R40}}  (Intel 82801DB/DBL/DBM audio controller (AC97)): PCM volume needs to be set under 80%, higher values cause clipping. Same with the Master channel as on T43.
-* Thinkpad {{Z61e}} (Intel High Definition with AD1981): Just turn down the PCM channel volume to around 77% and you should be happy, the Master Channel can be kept at 100%. If that doesn't help, load snd-hda-intel with model=thinkpad and position_fix=1.
+* Thinkpad {{Z61e}} (Intel High Definition with AD1981): Just turn down the PCM channel volume to at least 77% and you should be happy (in some combination with external speakers, 65% was needed), the Master Channel can be kept at 100%. If that doesn't help, loading snd-hda-intel with model=thinkpad and position_fix=1 might also improve a bit.

← Older revision		Revision as of 09:49, 15 June 2007
Line 9:		Line 9:
	* ThinkPad {{T43}} ([[AD1981B]] audio controller): PCM channel volume higher than 70% may result in clipping, regardless of the Master channel.		* ThinkPad {{T43}} ([[AD1981B]] audio controller): PCM channel volume higher than 70% may result in clipping, regardless of the Master channel.
	* ThinkPad {{R40}} (Intel 82801DB/DBL/DBM audio controller (AC97)): PCM volume needs to be set under 80%, higher values cause clipping. Same with the Master channel as on T43.		* ThinkPad {{R40}} (Intel 82801DB/DBL/DBM audio controller (AC97)): PCM volume needs to be set under 80%, higher values cause clipping. Same with the Master channel as on T43.
		+	* Thinkpad {{Z61e}} (Intel High Definition with AD1981): Just turn down the PCM channel volume to around 77% and you should be happy. If that doesn't help, load the snd-hda-intel with model=thinkpad and position_fix=1.