USB Mic - Signal to Noise Levels

trine wrote on 6/12/2009, 8:57 AM
Greetings,

I just purchased a Samson CO1U USB mic. I plugged it in and was able to record right away.

My problem is this.

I see levels of -21.6 for my speaking into the mic without yelling. I have a "noise" floor of about -66.2.

It seems to me that this is a roughly a 3-1 ratio - which is bad. What can I do to increase the disparity?

When I see the finished waveform on the track there are just little blips where I am speaking. It seems ridiculous. When I Normalize of course it takes all the noise up with it.

Shouldn't I just be able to plug in the USB mic and just record spoken word rather easily without a lot of noise?

Vegas 6 with C-Media Wave Device
I also have a MAudio Delta 44 with ASIO, but I don't know if that would be any better.

Thanks

Comments

musicvid10 wrote on 6/12/2009, 6:49 PM
In your Record options for your sound card or on the external interface (if present) there should be a Mic/Line switch or a +20dB boost button (same thing). Activate it.

From there, you should be able to adjust your input volume accordingly
Geoff_Wood wrote on 6/12/2009, 6:58 PM
Check your Samson manual. There is nothing in Vegas (or any application) that can affect the level coming from the mic. That is set between the mic and it's driver - check the driver for the previously-mention gained button.

geoff
gpsmikey wrote on 6/13/2009, 9:57 PM
On my Logitech USB mic, you can adjust the volume by going to Control Panel -> Sounds and Audio Devices, on the "Audio" tab, there is a section for "Sound Recording" and there is a "Volume" button there that can be adjusted. You may have the same feature with your USB device. (this is under windows XP Pro)

mikey
R0cky wrote on 6/19/2009, 9:06 AM
44.6 dB s/n is 29,000:1, not 3:1 or about 170:1 in voltage levels. Power is proportional to the voltage ratio squared.

While not great, it is typical for a lot of economy microphones. I looked at the data sheet and Samson does not specify the s/n which means it likely isn't particularly good. The noise of the electronics and converters in the mike also contribute.

You will have to turn up the gain somewhere and unless there is a control in the Samson driver (if there is one) that allows you to turn up the gain in the mike before the conversion, the signal is already converted to digital by the mike and it doesn't matter very much where you do it as it will be a digital multiplication no matter what.