Strange Effect On Low Frequencies

[mcavoybn]

To The Lords of Audacity Forums,

I have used audacity 1.2.6 for a long time to record fun little songs, nothing too serious. I have used either a mic placed next to my (guitar) amp or a direct input from my amplifiers output, to the input on the computer. This was on my HP pavilion a1160n Desktop.

However, recently I bought a toshiba satellite l505d laptop (Windows 7 64-bit, 4gb RAM, AMD Turion II Dual-Core Mobile M500 2.20 GHz). It uses realtek HD drivers/soundcard (I havent found much info on what kind of card it exactly is, but thats what i have, yes i have looked.) And when i downloaded and installed Audacity 1.2.6, I noticed a strange effect on my recordings when i recorded using the same equipment and programs as i did on the desktop i had used previously. Here's an example:

http://www.megaupload.com/?d=Y3JT8TF7

As i go to lower notes/frequencies the volume goes down, and a strange phaser/flanger effect happens, something i cannot describe. This happens with both the mic and the direct hookup from the amp to the computer.

There is nothing wrong with the amp, or the wires running to the computer, so i'm guessing there is something wrong with audacity or the sound card?
ANY help would be greatly appreciated, thank you.

[kozikowski]

Your new computer is designed for Skype phone calls to the corporate head office, it's not a general computer like the old one was.

First, did you find a Line-In on the side of the laptop? My guess is no. Many Windows machines only have high sensitivity, low level, mono Mic-In. If you're careful, you can get that to work, but the powerful signal direct from the amplifier is likely to cause problems.

In addition, there are now settings in the Windows Control Panels for Echo Cancellation and Conference Delay Management, no doubt missing from your old machine. Of course, they're not called that by name. Each manufacturer has a special name for them, so you get to dig around and see.

If you hit the signal level match and manage to turn all the enhanced services off, it should work just like your old one did -- except for one other thing. You should be in Audacity 1.3.12. Audacity 1.2 is not supported in newer computers and is no longer being updated.

http://audacityteam.org/download/

Koz

[mcavoybn]

Koz,

Yes there is a Line-In on the side of the laptop, that is what i am using, it gets the best sound. I'm using a simple cable with one 1/4" jack on one end and a 3.5mm jack on the other, which is what is going in the computer, coming directly from the amps output (a VOX ad15vt).

I'll check for all the settings you mentioned and shut them off. Thank You.

Also, the old machine was running on Windows Vista Home Premium (sigh) if that gives you any more ideas, and the driver version for the Realtek HD audio drivers is 6.0.1.5904, I have DirectX 11 and the audio codec is ALC272.

Thanks