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  1. As we all know, analog signals need to be attenuated to below 0db in order to prevent clipping when converting to digital. VHS audio signals are usually pretty hot, so I have been questioning whether or not to run the rca stereo signal through an analog mixer to bring down the gain before it hits my capture device. I've experimented with reducing the analog input gain in Virtualdub's audio settings, which seems to work, but when I looked closely at the waveform, it seemed kinda brickwalled. I'm wondering if the audio input setting in Vdub is bringing down the signal post a/d conversion, which would mean it simply attenuates a clipped signal. Am I mistaken on this assumption? Once I get some rca to xlr cables, I'll be running a test to compare methods. Who knows, maybe the analog mixer will add some extra analog goodness to the audio.
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    It depends on your converter hardware and drivers. Windows/Sound/Recording/Levels is only going to adjust the post-conversion gain. I use an Osprey card that has an analog gain control accessed from a custom dialog; it allows me to bring down hot sources and avoid analog clipping distortion. Previously, I used an analog mixer for the same purpose. Your VHS audio is already analog so a mixer is not going to add any goodness, only noise.
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  3. Thanks for your input, JVRaines. Much appreciated. Those Osprey cards look nice. I noticed they can capture balanced audio as well. Have you had good experiences with the Osprey? Seems like a solid choice, though a bit on the expensive side.
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  4. You should normalize input level in area around -3dBFS (no peak above this level). easiest way to configure level is recorded sinewave (commonly this is 1kHz). you can search for such signal. alternatively you can adjust signal level with help of spectrum analyzer - with some tries and time you can quickly realize where how to set level without distorting signal (normal spectrum on VHS is usually limited to 8 - 10kHz, above there is only noise and perhaps some frequencies related to horizontal deflection signal leaking to audio path).
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    Originally Posted by CountChocula View Post
    Thanks for your input, JVRaines. Much appreciated. Those Osprey cards look nice. I noticed they can capture balanced audio as well. Have you had good experiences with the Osprey? Seems like a solid choice, though a bit on the expensive side.
    It works quite well. I chose it because the driver exposes more functions of the chipset than most other cards and reflects a deep understanding of analog processing. You can usually find a used 260e for a reasonable price on eBay. I happen to have a spare card available; PM if you're interested.
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