Other hardware - Revision history

Artoria2e5: /* Headphones */

2024-08-06T03:57:18Z

Headphones

← Older revision		Revision as of 03:57, 6 August 2024
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	* Supra-aural - sits on the ear		* Supra-aural - sits on the ear
	* circumaural - completely cover the ear		* circumaural - completely cover the ear

			Supra-aural and circumaural headphones have the sound reshaped by your auricle. The other two styles feed sound more or less directly into the ear canal. This difference is important for deciding on what kind of HRTF to use.

	Terminology used for comparing headphones		Terminology used for comparing headphones
	* Noise Cancelling		* Noise Cancelling
	** active		** active: the headphone samples outside noise in real time and emits the opposite soundwave (for some frequencies).
	** passive		** passive: would be more "blocking" than "cancelling" -- think about an earmuff.

	* Frequency response - The range of frequencies the headphones can reproduce		* Frequency response - The range of frequencies the headphones can reproduce

	* Impedance - Doesn't mean much by itself, but in general, impedence should be matched across a system.		* Impedance - Doesn't mean much by itself, but in general, impedence should be matched across a system.

	* SPL@1kHz, 1V rms - [http://en.wikipedia.org/wiki/Sound_pressure_level#SPL_in_audio_equipment Sound Pressure Level]. How efficient the unit converts electrical energy to sound energy.		* SPL@1kHz, 1V rms - [http://en.wikipedia.org/wiki/Sound_pressure_level#SPL_in_audio_equipment Sound Pressure Level]. How efficient the unit converts electrical energy to sound energy.
			* Neodymium - The magnet of choice for high end headphones.

	* Neodymium - The magnet of choice for high end headphones.
	Popular Headphones		Popular Headphones
	* Sub $30		* Sub $30

Artoria2e5: /* Operating systems */ ~

2024-08-06T03:48:43Z

Operating systems: ~

← Older revision		Revision as of 03:48, 6 August 2024
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	Bluetooth codec support is not great on Windows. Windows 10 has SBC and AptX. Windows 11 introduces AAC as a better-than-SBC fallback on non-Qualcomm devices; it also introduces LE Audio support. There is no support for any codec variant such as AptX-HD. You can use a [https://www.bluetoothgoodies.com/a2dp/ third-party driver] ($5.99 trialware) that does A2DP its own way to get the better codecs.		Bluetooth codec support is not great on Windows. Windows 10 has SBC and AptX. Windows 11 introduces AAC as a better-than-SBC fallback on non-Qualcomm devices; it also introduces LE Audio support. There is no support for any codec variant such as AptX-HD. You can use a [https://www.bluetoothgoodies.com/a2dp/ third-party driver] ($5.99 trialware) that does A2DP its own way to get the better codecs.

	With PipeWire and BlueZ 5, Linux has support for many codecs: AptX (including LL and HD), LDAC, FastStream, both versions of Opus, LC3plus, and SBC XQ. The modern, PipeWire-based Linux audio stack can have very low software latency when combined with ~~RTKit~~. Combined with a low-latency codec, one ''should'' receive a relatively low-latency experience.		With PipeWire and BlueZ 5, Linux has support for many codecs: AptX (including LL and HD), LDAC, FastStream, both versions of Opus, LC3plus, and SBC XQ. The modern, PipeWire-based Linux audio stack can have very low software latency when combined with linux-rt or rtkit. Combined with a low-latency codec, one ''should'' receive a relatively low-latency experience.

	macOS and iOS are known to support AAC. SBC support is presumed to exist. There [https://gist.github.com/dvf/3771e58085568559c429d05ccc339219 used to be] support for AptX.		macOS and iOS are known to support AAC. SBC support is presumed to exist. There [https://gist.github.com/dvf/3771e58085568559c429d05ccc339219 used to be] support for AptX.

Artoria2e5: /* Operating systems */

2024-08-06T03:48:05Z

Operating systems

← Older revision		Revision as of 03:48, 6 August 2024
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	=== Operating systems ===		=== Operating systems ===

	Bluetooth codec support is not great on Windows. Windows 10 has SBC and AptX. Windows 11 introduces AAC as a better-than-SBC fallback on non-Qualcomm devices; it also introduces LE Audio support. There is no support for any codec variant such as AptX-HD. You can use a [https://www.bluetoothgoodies.com/a2dp/ third-party driver] that does A2DP its own way to get the better codecs.		Bluetooth codec support is not great on Windows. Windows 10 has SBC and AptX. Windows 11 introduces AAC as a better-than-SBC fallback on non-Qualcomm devices; it also introduces LE Audio support. There is no support for any codec variant such as AptX-HD. You can use a [https://www.bluetoothgoodies.com/a2dp/ third-party driver] ($5.99 trialware) that does A2DP its own way to get the better codecs.

	With PipeWire and BlueZ 5, Linux has support for many codecs: AptX (including LL and HD), LDAC, FastStream, both versions of Opus, LC3plus, and SBC XQ. The modern, PipeWire-based Linux audio stack can have very low software latency when combined with RTKit. Combined with a low-latency codec, one ''should'' receive a relatively low-latency experience.		With PipeWire and BlueZ 5, Linux has support for many codecs: AptX (including LL and HD), LDAC, FastStream, both versions of Opus, LC3plus, and SBC XQ. The modern, PipeWire-based Linux audio stack can have very low software latency when combined with RTKit. Combined with a low-latency codec, one ''should'' receive a relatively low-latency experience.

Artoria2e5: /* Bluetooth / add / Operating systems */

2024-08-06T03:46:53Z

Bluetooth: add Operating systems

← Older revision		Revision as of 03:46, 6 August 2024
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	In any case, it's much better than SBC and retains the low complexity character. When given more bits, such as with the 962 and 1242 standard profiles, it can be very acceptable. Google's open source [https://github.com/google/liblc3 liblc3] implementation is written to the word of the BT spec.		In any case, it's much better than SBC and retains the low complexity character. When given more bits, such as with the 962 and 1242 standard profiles, it can be very acceptable. Google's open source [https://github.com/google/liblc3 liblc3] implementation is written to the word of the BT spec.

			=== Operating systems ===

			Bluetooth codec support is not great on Windows. Windows 10 has SBC and AptX. Windows 11 introduces AAC as a better-than-SBC fallback on non-Qualcomm devices; it also introduces LE Audio support. There is no support for any codec variant such as AptX-HD. You can use a [https://www.bluetoothgoodies.com/a2dp/ third-party driver] that does A2DP its own way to get the better codecs.

			With PipeWire and BlueZ 5, Linux has support for many codecs: AptX (including LL and HD), LDAC, FastStream, both versions of Opus, LC3plus, and SBC XQ. The modern, PipeWire-based Linux audio stack can have very low software latency when combined with RTKit. Combined with a low-latency codec, one ''should'' receive a relatively low-latency experience.

			macOS and iOS are known to support AAC. SBC support is presumed to exist. There [https://gist.github.com/dvf/3771e58085568559c429d05ccc339219 used to be] support for AptX.

	== Headphones ==		== Headphones ==

Artoria2e5: /* Bluetooth */

2023-08-25T00:04:24Z

Bluetooth

← Older revision		Revision as of 00:04, 25 August 2023
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	== Bluetooth ==		== Bluetooth ==

	Bluetooth has two unusual requirements: codec complexity and latency. Complexity decides battery life, but with the codec doing less work, it's not usual to see bitrate/quality trades way worse than conventional codecs.		Bluetooth has two unusual requirements: codec complexity and latency. Complexity (bitrate too, to an extent) decides battery life, but with the codec doing less work, it's not usual to see bitrate/quality trades way worse than conventional codecs.

	=== A2DP ===		=== A2DP ===

Artoria2e5: /* LC3 */

2023-08-25T00:03:32Z

LC3

← Older revision		Revision as of 00:03, 25 August 2023
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	* LC3plus, LC3's "high-res" cousin available over A2DP, is [https://hydrogenaud.io/index.php/topic,121850.0.html worse than Apple and Android (FDK) AAC at 144 kbps]. The Japan Audio Society nevertheless thinks that's enough for a "Hi-Res AUDIO WIRELESS" sticker.		* LC3plus, LC3's "high-res" cousin available over A2DP, is [https://hydrogenaud.io/index.php/topic,121850.0.html worse than Apple and Android (FDK) AAC at 144 kbps]. The Japan Audio Society nevertheless thinks that's enough for a "Hi-Res AUDIO WIRELESS" sticker.

	In any case, it's much better than SBC and retains the low complexity character. ~~It is not the best use of~~ the ~~bandwidth available~~, ~~but a lot of things~~ can be ~~excused with "low complexity"~~. Google's open source [https://github.com/google/liblc3 liblc3] implementation is written to the word of the BT spec.		In any case, it's much better than SBC and retains the low complexity character. When given more bits, such as with the 962 and 1242 standard profiles, it can be very acceptable. Google's open source [https://github.com/google/liblc3 liblc3] implementation is written to the word of the BT spec.

	== Headphones ==		== Headphones ==

Artoria2e5: /* LC3 */

2023-08-25T00:01:14Z

LC3

← Older revision		Revision as of 00:01, 25 August 2023
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	* It's [https://www.etsi.org/deliver/etsi_tr/103500_103599/103590/01.01.01_60/tr_103590v010101p.pdf allegedly] "better than Opus" with respect to error tolerance in speech environments. Except the test is done with speech samples in the non-speech, non-FEC mode of Opus (CELT), at minimum complexity (effort), and an old version at that.		* It's [https://www.etsi.org/deliver/etsi_tr/103500_103599/103590/01.01.01_60/tr_103590v010101p.pdf allegedly] "better than Opus" with respect to error tolerance in speech environments. Except the test is done with speech samples in the non-speech, non-FEC mode of Opus (CELT), at minimum complexity (effort), and an old version at that.
	* No [[joint stereo]] is available.		* No [[joint stereo]] is available. The rationale given is that this allows True Wireless Stereo (TWS) to work with the audio source transmitting direct to each headphone, without needing an intermediate decode.
	* LC3plus, LC3's "high-res" cousin available over A2DP, is [https://hydrogenaud.io/index.php/topic,121850.0.html worse than Apple and Android (FDK) AAC at 144 kbps]. The Japan Audio Society nevertheless thinks that's enough for a "Hi-Res AUDIO WIRELESS" sticker.		* LC3plus, LC3's "high-res" cousin available over A2DP, is [https://hydrogenaud.io/index.php/topic,121850.0.html worse than Apple and Android (FDK) AAC at 144 kbps]. The Japan Audio Society nevertheless thinks that's enough for a "Hi-Res AUDIO WIRELESS" sticker.

Artoria2e5: /* LC3 */

2023-07-16T05:14:21Z

LC3

← Older revision		Revision as of 05:14, 16 July 2023
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	==== LC3 ====		==== LC3 ====
	: ''See ~~Wikipedia~~: [[Wikipedia:LC3~~\|LC3~~]]''		: ''See also: [[Wikipedia:LC3 (codec)]]''
	[https://www.bluetooth.org/DocMan/handlers/DownloadDoc.ashx?doc_id=502107&vId=542963 LC3] is the baseline LE Audio codec. It uses some of the same ideas as Opus CELT, but comes with some new patented techniques and runs at extremely low complexity.		[https://www.bluetooth.org/DocMan/handlers/DownloadDoc.ashx?doc_id=502107&vId=542963 LC3] is the baseline LE Audio codec. It uses some of the same ideas as Opus CELT, but comes with some new patented techniques and runs at extremely low complexity.

Artoria2e5: /* LC3 */

2023-07-16T05:13:58Z

LC3

← Older revision		Revision as of 05:13, 16 July 2023
Line 42:		Line 42:

	==== LC3 ====		==== LC3 ====
	[LC3 https://www.bluetooth.org/DocMan/handlers/DownloadDoc.ashx?doc_id=502107&vId=542963] is the baseline LE Audio codec. It uses some of the same ideas as Opus CELT, but comes with some new patented techniques and runs at extremely low complexity.		: ''See Wikipedia: [[Wikipedia:LC3\|LC3]]''
			[https://www.bluetooth.org/DocMan/handlers/DownloadDoc.ashx?doc_id=502107&vId=542963 LC3] is the baseline LE Audio codec. It uses some of the same ideas as Opus CELT, but comes with some new patented techniques and runs at extremely low complexity.

	* It's [https://www.etsi.org/deliver/etsi_tr/103500_103599/103590/01.01.01_60/tr_103590v010101p.pdf allegedly] "better than Opus" with respect to error tolerance in speech environments. Except the test is done with speech samples in the non-speech, non-FEC mode of Opus (CELT), at minimum complexity (effort), and an old version at that.		* It's [https://www.etsi.org/deliver/etsi_tr/103500_103599/103590/01.01.01_60/tr_103590v010101p.pdf allegedly] "better than Opus" with respect to error tolerance in speech environments. Except the test is done with speech samples in the non-speech, non-FEC mode of Opus (CELT), at minimum complexity (effort), and an old version at that.
Line 48:		Line 49:
	* LC3plus, LC3's "high-res" cousin available over A2DP, is [https://hydrogenaud.io/index.php/topic,121850.0.html worse than Apple and Android (FDK) AAC at 144 kbps]. The Japan Audio Society nevertheless thinks that's enough for a "Hi-Res AUDIO WIRELESS" sticker.		* LC3plus, LC3's "high-res" cousin available over A2DP, is [https://hydrogenaud.io/index.php/topic,121850.0.html worse than Apple and Android (FDK) AAC at 144 kbps]. The Japan Audio Society nevertheless thinks that's enough for a "Hi-Res AUDIO WIRELESS" sticker.

	In any case, it's much better than SBC and retains the low complexity character. It is not the best use of the bandwidth available, but is ~~good enough~~ to ~~be accepted as a new thing and charge patent fees for~~.		In any case, it's much better than SBC and retains the low complexity character. It is not the best use of the bandwidth available, but a lot of things can be excused with "low complexity". Google's open source [https://github.com/google/liblc3 liblc3] implementation is written to the word of the BT spec.

	== Headphones ==		== Headphones ==

Artoria2e5: /* LC3 */

2023-07-16T05:12:18Z

LC3

← Older revision		Revision as of 05:12, 16 July 2023
Line 42:		Line 42:

	==== LC3 ====		==== LC3 ====
	LC3 is the baseline codec. It uses some of the same ideas as Opus CELT, but comes with some new patented techniques and runs at extremely low complexity.		[LC3 https://www.bluetooth.org/DocMan/handlers/DownloadDoc.ashx?doc_id=502107&vId=542963] is the baseline LE Audio codec. It uses some of the same ideas as Opus CELT, but comes with some new patented techniques and runs at extremely low complexity.

	* It's [https://www.etsi.org/deliver/etsi_tr/103500_103599/103590/01.01.01_60/tr_103590v010101p.pdf allegedly] "better than Opus" with respect to error tolerance in speech environments. Except the test is done with speech samples in the non-speech, non-FEC mode of Opus (CELT), at minimum complexity (effort), and an old version at that.		* It's [https://www.etsi.org/deliver/etsi_tr/103500_103599/103590/01.01.01_60/tr_103590v010101p.pdf allegedly] "better than Opus" with respect to error tolerance in speech environments. Except the test is done with speech samples in the non-speech, non-FEC mode of Opus (CELT), at minimum complexity (effort), and an old version at that.
			* No [[joint stereo]] is available.
	* LC3plus, LC3's "high-res" cousin available over A2DP, is [https://hydrogenaud.io/index.php/topic,121850.0.html worse than Apple and Android (FDK) AAC at 144 kbps]. The Japan Audio Society nevertheless thinks that's enough for a "Hi-Res AUDIO WIRELESS" sticker.		* LC3plus, LC3's "high-res" cousin available over A2DP, is [https://hydrogenaud.io/index.php/topic,121850.0.html worse than Apple and Android (FDK) AAC at 144 kbps]. The Japan Audio Society nevertheless thinks that's enough for a "Hi-Res AUDIO WIRELESS" sticker.

			In any case, it's much better than SBC and retains the low complexity character. It is not the best use of the bandwidth available, but is good enough to be accepted as a new thing and charge patent fees for.

	== Headphones ==		== Headphones ==

Other hardware - Revision history

Artoria2e5: /* Headphones */

Artoria2e5: /* Operating systems */ ~

Artoria2e5: /* Operating systems */

Artoria2e5: /* Bluetooth */ add /* Operating systems */

Artoria2e5: /* Bluetooth */

Artoria2e5: /* LC3 */

Artoria2e5: /* LC3 */

Artoria2e5: /* LC3 */

Artoria2e5: /* LC3 */

Artoria2e5: /* LC3 */

Artoria2e5: /* Bluetooth / add / Operating systems */