$ more /proc/asound/cards
 0 [ALSA           ]: bcm2835 - bcm2835 ALSA
                      bcm2835 ALSA
 1 [Device         ]: USB-Audio - USB PnP Audio Device
                      USB PnP Audio Device at usb-3f980000.usb-1.4, full speed

# more /proc/asound/cards
 0 [seeed2micvoicec]: seeed-2mic-voic - seeed-2mic-voicecard
                      seeed-2mic-voicecard
#

A lot of times when sound applications seem to fail, it is because we forget to turn up the volume.

Volume adjustment can be done with alsamixer. This program makes use of some function keys (F1, F2, etc).

$ alsamixer

F6 to select between sound cards
F3 to select playback volume (for speaker)
F4 to select capture volume (for mic)
⬆ ⬇ arrow keys to adjust
Esc to exit

$ speaker-test -t wav

Press Ctrl-C when done.

Enter this command, then speak to the mic, press Ctrl-C when you are finished:

$ arecord -D plughw:0,0 abc.wav

-D plughw:0,0 tells arecord where the device is. In this case, device is the mic. It is at index 0.

plughw:1,0 actually refers to "Sound Card index 1, Subdevice 0", because a sound card may house many subdevices. Here, we don't care about subdevices and always give it a 0. The only important index is the sound card's.

$ aplay -D plughw:0,0 abc.wav

Here, we tell aplay to play to plughw:0,0, which refers to "Sound Card index 0, Subdevice 0", which leads to the speaker.

If you aplay and arecord successfully, that means the speaker and microphone are working properly. We can move on to add more capabilities.

$ pico2wave -w abc.wav "Good morning. How are you today?"
$ aplay -D plughw:0,0 abc.wav

$ pocketsphinx_continuous -adcdev plughw:0,0 -inmic yes
$ pocketsphinx_continuous -adcdev plughw:0,0 -hmm /usr/share/pocketsphinx/model/lm/ru/zero_ru.cd_semi_4000/ -jsgf /root/assist/speech/gr.gram -dict /root/assist/speech/ru.dic  -inmic yes

pocketsphinx_continuous interprets speech in real-time. It will spill out a lot of stuff, ending with something like this:

Warning: Could not find Capture element
READY....

Now, speak into the mic, and note the results. At first, you may find it funny. After a while, you realize it is horribly inaccurate.

For it to be useful, we have to make it more accurate.

echo "Система умного вигвама приветствует вас" | RHVoice-test -p Anna

espeak "Text you wish to hear back"
espeak "Text you wish to hear back" -w test.wav
aplay test.wav
espeak  -vru "Русский синтезатор речи"

spd-say -o rhvoice -t female1 "hello"
echo "Проверка синтезатора речи2" | spd-say -o rhvoice -l ru -e -t male1

python3 demo.py resources/models/jarvis.umdl