Hello to all. I need reassurance on this: do sound cards have actual electronic potentiometers that are adjusted by the Windows mixer to set playback and recording levels? Thanks in advance.
Most consumer cards have "mixers" that allow one to adjust volume, and some other audio parameters. You can't physically tweak anything on an internal card. You might be able to on external cards. Pro cards usually do not, requiring an outboard mixer or other type of volume attenuator.
In a perfect world, the sound card should be flat. Then you can take things to Audition/CEP and screw things up how you like it there (post mastering).
AFAIK, no. The windows mixer sets the playback and recording levels in the digital domain. In order to avoid any software processing and audio quality loss, the levels should be set at 100%. The master output volume is usually hardware-accelerated, though.
Digitally, in Windows...most are quite crude, too. It's next to impossible to get things exact, especially the balance. I understant the M-Audio Revolution 7 card has a better balance control, at least.
Hi Pablo. Gut instinct tells me "no", but only the card manufacturer would know for sure. You can theoretically use a digital control to change the gain of, say, a transistor, to change the volume in the analog domain, but I doubt the consumer cards would go to that much trouble. Most of the semi-pro and pro cards just do an analog-to-digital conversion, relying on an outboard device to control the volume. I do that with my M-Audio setup. Works quite well.
Thanks for the replies. Now I'm really confused: Say you provide the sound card a strong enough signal so the ADC in the card fills the bits, 0dB. I can do this at any setting of the recording level slider in the Windows mixer, right? So if I increase the volume in the windows mixer, where does the extra numbers come from?
Pablo, I suggest that you record at 24 or 32-bits, if you can. Then you won't have to worry about resolution.
I found a block diagram of a SoundBlaster card. The article at http://home.global.co.za/~born2run/hardware.htm indicates: "- The mixer Mixes and controls the volumes of: The synthesizers (EMU + OPL) The wave audio playback Line input Microphone input CD audio input (on-board connector) PC speaker input (on-board connector) Does AGC (automatic gain control) on the mic input Sends selected channels to the wave audio ADC for recording Controls volume, bass & treble of the stereo output signal, which finally is fed to the Line Out and through a lousy amp to the Speaker Out connectors " So it seems clear that sound cards have internal pots or probably amps for level control, and they are adjusted via the Windows mixer through the driver. And if it is an amp, the final gain stage of the chain before the ADC is a crappy IC.
