I have a USB microphone.
$ arecord -l
**** List of CAPTURE Hardware Devices ****
card 1: Device [USB PnP Sound Device], device 0: USB Audio [USB Audio]
Subdevices: 1/1
Subdevice #0: subdevice #0
$ cat /proc/asound/cards
0 [ALSA ]: bcm2835 - bcm2835 ALSA
bcm2835 ALSA
1 [Device ]: USB-Audio - USB PnP Sound Device
C-Media Electronics Inc. USB PnP Sound Device at usb-20980000.usb-1.4, full spe
But when I run alsamixer, I get the following:
This sound device does not have any capture controls.
The problem is that the recording sound level is to low, and I want to increase the microphone sensitivity. How can I do that?
$ arecord -D plughw:1 -d 5 -vv ~/rectest.wav
Recording WAVE '/home/pi/rectest.wav' : Unsigned 8 bit, Rate 8000 Hz, Mono
Plug PCM: Rate conversion PCM (48000, sformat=S16_LE)
Converter: libspeex (builtin)
Protocol version: 10002
Its setup is:
stream : CAPTURE
access : RW_INTERLEAVED
format : U8
subformat : STD
channels : 1
rate : 8000
exact rate : 8000 (8000/1)
msbits : 8
buffer_size : 4000
period_size : 1000
period_time : 125000
tstamp_mode : NONE
period_step : 1
avail_min : 1000
period_event : 0
start_threshold : 1
stop_threshold : 4000
silence_threshold: 0
silence_size : 0
boundary : 262144000
Slave: Hardware PCM card 1 'USB PnP Sound Device' device 0 subdevice 0
Its setup is:
stream : CAPTURE
access : MMAP_INTERLEAVED
format : S16_LE
subformat : STD
channels : 1
rate : 48000
exact rate : 48000 (48000/1)
msbits : 16
buffer_size : 24006
period_size : 6000
period_time : 125000
tstamp_mode : NONE
period_step : 1
avail_min : 6000
period_event : 0
start_threshold : 6
stop_threshold : 24006
silence_threshold: 0
silence_size : 0
boundary : 1573257216
appl_ptr : 0
hw_ptr : 0
##+ | 03%
