3 ms·
Regarding the sound card, from the description it looks like the "crappy" sound card also employs a high-pass filter. Is there a reason for it? What kind of ci
by tenfingers 12y ago
Regarding the sound card, from the description it looks like the "crappy" sound card also employs a high-pass filter.
Is there a reason for it? What kind of circuit design in the DAC could cause low frequencies/significant distortion to require a high-pass at these frequency ranges?
Genuine curiosity here.
- mmaldacker 12y agoIt's a low pass filter. And I'm assuming the low-pass is used in the DAC to cut off high frequencies it cannot handle.
- boomlinde 12y agoWhat frequency ranges do you mean? Digitally, you can feed the output very-close-to 0 Hz signals. Without a high-pass filter, this essentially means outputting direct current. A lot of audio gear don't take kindly to DC signals various reasons; things like amplifiers or headphones.
- cnvogel 12y agoMost PC sound cards employ so-called single-supply designs running their chips only between Ground and a single positive supply, e.g. 5V or 3.3V. So typically for a headphone output the amplifier will swing around 1.5 or 2.5V or so. To get rid of this offset, a capacitor is used. This capacitor, together with the headphones impedance, will function as a RC hipass.
- tenfingers 12y agoThanks for the explanation!