# Audio ## Audio > An audio signal is a representation of sound, typically as an electrical voltage. Audio signals have frequencies in the audio frequency range of roughly 20 to 20,000 Hz (the limits of human hearing). [wikipedia](https://en.wikipedia.org/wiki/Audio_signal) * [Intel Edison Audio Setup Guide](http://download.intel.com/support/edison/sb/edisonaudio_332434001.pdf) * [Edidoom Intel Edison Audio](https://github.com/llatta/edison-audio) * [Play Audio from your Intel® Edison via Bluetooth\* using Advanced Audio Distribution Profile (A2DP)](https://software.intel.com/en-us/articles/play-audio-from-your-intel-edison-via-bluetooth-using-advanced-audio-distribution-profile) * [Intel Edison - Simple I2S Audio Setup](http://www.malinov.com/Home/sergey-s-blog/inteledison-simplei2saudiosetup) ## Required Hardware USB Audio Dongle USB PnP Sound Device ## Kernel Integration > Advanced Linux Sound Architecture > > > The Advanced Linux Sound Architecture (ALSA) provides audio and MIDI functionality to the Linux operating system. * [Advanced Linux Sound Architecture Homepage](http://www.alsa-project.org/main/index.php/Main_Page) ### Kernel Display Message ```bash root@edison:~# dmesg ... [ 3750.683557] hub 1-0:1.0: USB hub found [ 3750.683602] hub 1-0:1.0: 1 port detected [ 3750.684174] dwc3-host dwc3-host.2: xHCI Host Controller [ 3750.684573] dwc3-host dwc3-host.2: new USB bus registered, assigned bus number 2 [ 3750.684764] usb usb2: New USB device found, idVendor=1d6b, idProduct=0003 [ 3750.684789] usb usb2: New USB device strings: Mfr=3, Product=2, SerialNumber=1 [ 3750.684809] usb usb2: Product: xHCI Host Controller [ 3750.684829] usb usb2: Manufacturer: Linux 3.10.98-poky-edison+ dwc-xhci [ 3750.684848] usb usb2: SerialNumber: dwc3-host.2 [ 3750.688503] xHCI xhci_add_endpoint called for root hub [ 3750.688527] xHCI xhci_check_bandwidth called for root hub [ 3750.688852] hub 2-0:1.0: USB hub found [ 3750.688899] hub 2-0:1.0: 1 port detected [ 3750.749302] pmic_ccsm pmic_ccsm: USB VBUS Detected. Notifying OTG driver [ 3751.001112] usb 1-1: new full-speed USB device number 2 using dwc3-host [ 3751.023554] usb 1-1: New USB device found, idVendor=0d8c, idProduct=013c [ 3751.023585] usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=0 [ 3751.023607] usb 1-1: Product: USB PnP Sound Device [ 3751.055963] input: USB PnP Sound Device as /devices/pci0000:00/0000:00:11.0/dwc3-host.2/usb1/1-1/1-1:1.3/input/input7 [ 3751.056818] hid-generic 0003:0D8C:013C.0005: input,hidraw0: USB HID v1.00 Device [USB PnP Sound Device] on usb-dwc3-host.2-1/input3 ``` ### USB Devices ```bash root@edison:~# lsusb Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 002: ID 0d8c:013c C-Media Electronics, Inc. CM108 Audio Controller Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub ``` ## Userspace Interfaces ### ProcFs ```bash root@edison:~# cat /proc/asound/cards 0 [Loopback ]: Loopback - Loopback Loopback 1 1 [dummyaudio ]: dummy-audio - dummy-audio dummy-audio 2 [Device ]: USB-Audio - USB PnP Sound Device USB PnP Sound Device at usb-dwc3-host.2-1, full speed root@edison:~# ``` ## Applications / Libraries ### Setup #### Opkg ```bash root@edison:~# opkg install alsa-utils espeak ... Configuring libsamplerate0. Configuring libjack. Configuring alsa-utils-alsaloop. Configuring alsa-utils-alsaucm. Configuring alsa-utils-midi. Configuring alsa-utils-iecset. Configuring alsa-utils-aconnect. Configuring libportaudio2. Configuring espeak. Configuring alsa-utils-speakertest. Configuring alsa-utils-aseqnet. Configuring alsa-utils-aseqdump. Configuring alsa-utils. Configuring mpg123. ... ``` ```bash root@edison:~# opkg install --nodeps jack-dev Installing jack-dev (0.121.0-r0) on root. Downloading http://repo.opkg.net/edison/repo/core2-32/jack-dev_0.121.0-r0_core2-32.ipk. Configuring jack-dev. ``` ```bash root@edison:~# opkg install --nodeps libportaudio-dev Installing libportaudio-dev (v19+svnr1387-r0) on root. Downloading http://repo.opkg.net/edison/repo/core2-32/libportaudio-dev_v19+svnr1387-r0_core2-32.ipk. Configuring libportaudio-dev. root@edison:~# ``` #### Apt-Get ```bash root@edison:~# apt-get install alsa-utils mpg123 espeak ``` #### Free Sound Effects * [Soundbible](http://soundbible.com/) * [Soundjay](http://www.soundjay.com/) * [freeSFX](http://www.freesfx.co.uk/) #### Programs * [Mad](http://www.underbit.com/products/mad/) #### Audio Files ```bash root@edison:~# ls /usr/share/sounds/alsa/ Front_Center.wav Noise.wav Rear_Right.wav Front_Left.wav Rear_Center.wav Side_Left.wav Front_Right.wav Rear_Left.wav Side_Right.wav ``` ## List Capture Hardware Devices ```bash root@edison:~# arecord -l **** List of CAPTURE Hardware Devices **** card 0: Loopback [Loopback], device 0: Loopback PCM [Loopback PCM] Subdevices: 8/8 Subdevice #0: subdevice #0 Subdevice #1: subdevice #1 Subdevice #2: subdevice #2 Subdevice #3: subdevice #3 Subdevice #4: subdevice #4 Subdevice #5: subdevice #5 Subdevice #6: subdevice #6 Subdevice #7: subdevice #7 card 0: Loopback [Loopback], device 1: Loopback PCM [Loopback PCM] Subdevices: 8/8 Subdevice #0: subdevice #0 Subdevice #1: subdevice #1 Subdevice #2: subdevice #2 Subdevice #3: subdevice #3 Subdevice #4: subdevice #4 Subdevice #5: subdevice #5 Subdevice #6: subdevice #6 Subdevice #7: subdevice #7 card 1: dummyaudio [dummy-audio], device 0: 14 [] Subdevices: 1/1 Subdevice #0: subdevice #0 card 1: dummyaudio [dummy-audio], device 1: ((null)) [] Subdevices: 1/1 Subdevice #0: subdevice #0 card 1: dummyaudio [dummy-audio], device 2: ((null)) [] Subdevices: 1/1 Subdevice #0: subdevice #0 card 2: Device [USB PnP Sound Device], device 0: USB Audio [USB Audio] Subdevices: 1/1 Subdevice #0: subdevice #0 root@edison:~# ``` ## List Playback Hardware Devices ```bash root@edison:~# aplay -l **** List of PLAYBACK Hardware Devices **** card 0: Loopback [Loopback], device 0: Loopback PCM [Loopback PCM] Subdevices: 8/8 Subdevice #0: subdevice #0 Subdevice #1: subdevice #1 Subdevice #2: subdevice #2 Subdevice #3: subdevice #3 Subdevice #4: subdevice #4 Subdevice #5: subdevice #5 Subdevice #6: subdevice #6 Subdevice #7: subdevice #7 card 0: Loopback [Loopback], device 1: Loopback PCM [Loopback PCM] Subdevices: 8/8 Subdevice #0: subdevice #0 Subdevice #1: subdevice #1 Subdevice #2: subdevice #2 Subdevice #3: subdevice #3 Subdevice #4: subdevice #4 Subdevice #5: subdevice #5 Subdevice #6: subdevice #6 Subdevice #7: subdevice #7 card 1: dummyaudio [dummy-audio], device 0: 14 [] Subdevices: 1/1 Subdevice #0: subdevice #0 card 1: dummyaudio [dummy-audio], device 1: ((null)) [] Subdevices: 1/1 Subdevice #0: subdevice #0 card 1: dummyaudio [dummy-audio], device 2: ((null)) [] Subdevices: 1/1 Subdevice #0: subdevice #0 card 2: Device [USB PnP Sound Device], device 0: USB Audio [USB Audio] Subdevices: 1/1 Subdevice #0: subdevice #0 ``` ## Arecord / Aplay ```bash root@edison:~# arecord -f cd -D plughw:2,0 -d 20 test.wav # USB Recording WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo ^CAborted by signal Interrupt... root@edison:~# aplay -D hw:2,0 test.wav # USB Playing WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo ``` ### Device Configuration ```bash root@edison:~# vi ~/.asoundrc ``` ```bash pcm.!default { type plug slave { pcm "hw:2,0" } } ctl.!default { type plug slave { pcm "hw:2,0" } } ``` ```bash root@edison:~# arecord -f cd -d 20 test.wav Recording WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo ^CAborted by signal Interrupt... root@edison:~# aplay test.wav Playing WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo ``` ### Other Configuration ```bash pcm.!default { type asym playback.pcm { type plug slave.pcm "hw:2,0" } capture.pcm { type plug slave.pcm "hw:3,0" } } ctl.!default { type plug slave { pcm "hw:2,0" } } ``` ### Other Configuration ```bash pcm.!default { type asym playback.pcm { type plug slave.pcm "hw:2,0" } capture.pcm { type plug slave.pcm "hw:2,0" } } ``` ### Other Configuration ```bash root@edison:~# vi /etc/asound.conf pcm.!default sysdefault:Device ``` ``` root@edison:~# aplay -Ll root@edison:~# vi ~/.asoundrc root@edison:~# vi /etc/asound.conf pcm.!default sysdefault:Device root@edison:~# aplay /usr/share/sounds/alsa/Front_Center.wav root@edison:~# aplay -D hw:1,0 /usr/share/sounds/alsa/Front_Center.wav ``` ### Play Wav Sample File ```bash root@edison:~# aplay /usr/share/sounds/alsa/Front_Center.wav Playing WAVE '/usr/share/sounds/alsa/Front_Center.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Mo root@edison:~# aplay /usr/share/sounds/alsa/Rear_Center.wav Playing WAVE '/usr/share/sounds/alsa/Rear_Center.wav' : Signed 16 bit Little Endian, Rate 48000 Hz, Moo root@edison:~# ``` ### Speaker-Test ```bash root@edison:~# speaker-test speaker-test 1.0.28 Playback device is default Stream parameters are 48000Hz, S16_LE, 1 channels Using 16 octaves of pink noise ... ... ^C root@edison:~# ``` ## Mpg123 ```bash root@edison:~# mpg123 ``` ## Espeak ```bash root@edison:~# espeak ``` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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