I have a Creative Labs Modem Blaster modem and I am running Windows 2000. I am trying to send modem sound to a speaker from my VB app I am writing. However, the sound I am getting is very distorted. I think it has something to do with the AT commands I am sending because when I dial manually using the Windows Dialer, the sound is not distorted. Creative Labs was absolutely no help so any ideas anyone has would be greatly appreciated.
Tek-Tips is the largest IT community on the Internet today!
Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!
-
Congratulations Mike Lewis on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!
Modem sound distorted
- Thread starter sdillard
- Start date
Guest_imported
New member
- Jan 1, 1970
- 0
- 0
- 0
This probably isn't going to help much but... Audio usually sounds distorted for one of several reasons. Either the amplitude (level) of the signal is far too high and the signal peaks are being severely clipped, or the bandwidth of your signal far exceeds the dynamic range of the input circuitry, or you are feeding the signal into completely the wrong impedance, An example for the latter would be connecting a low impedance dynamic microphone into a high impedance input (for say a crystal insert) - this will produce distorted audio.
Good luck!
ROGER - GØAOZ.
Good luck!
ROGER - GØAOZ.
- Thread starter
- #4
I ended up using some OCX's from a company called Allen_Martin. They have demo's that you can download and try out before you buy them. With the straight AT commands, there doesn't appear to be a way to control the gain so the sound gets distorted. If you can find a WAVE recorder tool (like one from Allen_Martin) you can control the volume and gain.
The distortion could also come from the init string used on the modem. When you use it to dial an ISP through DUN, it's setting itself up for V.90 compression, and you need to cut it back to V.34 to get "normal" sounds.
In your VB app, when you init the modem, just put AT&F to init the modem. This will reset it back to Factory (the &F) which will probably get the desired result. If not, try this: AT&F+MS=V34,0 Cheers,
Jim
In your VB app, when you init the modem, just put AT&F to init the modem. This will reset it back to Factory (the &F) which will probably get the desired result. If not, try this: AT&F+MS=V34,0 Cheers,
Jim
- Status
