5 ms·

The "best" answer seems wrong or at best misleading -- I would be very very surprised if the user-visible OS master volume control, which typically controls the

The "best" answer seems wrong or at best misleading -- I would be very very surprised if the user-visible OS master volume control, which typically controls the sound card directly, was not directly controlling op-amp gain at some later stage of the sound card. Assuming this is true, the correct option would be to maximize any application volumes (e.g. YouTube), to maximize master volume to a level just below the sound clips (distorts) at the amplifier input, and to reduce the amplifier's pre-gain (if it has any) so the master volume control has a reasonable range. This method will minimize the three (not just one) culprits of poor computer audio quality: quantization at the application layer, electronic interference over the physical connection, and clipping at the pre-amp.

nitrogen 14y ago
Alsamixer for Linux makes this much easier, as it shows the actual level in dB (at least for any sound card I've ever owned). For example, 0dB (maximum volume without clipping) is at ~74/100 on one of my cards, not 100/100.
- davvid 14y ago
  This is true. This is hardware-specific, which you may have hinted at when you said "on one of my cards". The onboard Intel sound card on my Debian system shows 0dB at 100/100 in alsamixer.
scep12 14y ago
This is spot on - thanks for posting this. You shouldn't be putting your OS volume at 100% - I never put mine past 50% when i'm sending the signal out.
- davidcuddeback 14y ago
  > You shouldn't be putting your OS volume at 100% Isn't that only true if you're using your sound card's analog output? If you're using a digital output, I would imagine you would want to keep it at 0dB (no gain and no attenuation). Am I right or am I missing something?
  - scep12 14y ago
    Exactly. Digital volume is just smoke and mirrors. Turn it as high as you like - it's not going to distort. Any time you're going through a DA converter and controlling the volume after the conversion (at which point it's an analog manipulation) - which most OS-level volume controllers do - you should generally stay in the 50-75 range depending on the quality of you hardware. Some soundcards might break up at 25%, others might be okay at 100%. I find that 50% is usually safe, and any distortion at 75% is subtle and not offending.
mbell 14y ago
In most sound card designs I've seen there is a 'boost' switch on the output. In other words there is a toggle that enables a ~10dB boost on the output amplifier (or sometimes the DAC). The volume control is actually digital but when you hit a particular threshold the external boost is toggled on and digital volume adjusted to maintain a smooth level transition. If you keep going 'up' with the volume control your still changing the volume digital but you've now got an extra 10dB of gain on the output which can drive the output into clipping if the input signal is full range. EDIT: Just to add. I would be extremely surprised to see a sound card that isn't a full on pro model have true analog gain control. I've designed a couple products with such controls (for pre-amp gain, but a similar concept) and you need digitally controlled resistors to accomplish it. They are large, expensive and touchy to route without inducing noise. As an example: http://www.analog.com/en/digital-to-analog-converters/digital-potentiometers/ad5246/products/product.html http://www.analog.com/en/digital-to-analog-converters/digita...

nitrogen 14y ago

Alsamixer for Linux makes this much easier, as it shows the actual level in dB (at least for any sound card I've ever owned). For example, 0dB (maximum volume without clipping) is at ~74/100 on one of my cards, not 100/100.

davvid 14y ago
This is true. This is hardware-specific, which you may have hinted at when you said "on one of my cards". The onboard Intel sound card on my Debian system shows 0dB at 100/100 in alsamixer.

scep12 14y ago

This is spot on - thanks for posting this. You shouldn't be putting your OS volume at 100% - I never put mine past 50% when i'm sending the signal out.

davidcuddeback 14y ago
> You shouldn't be putting your OS volume at 100% Isn't that only true if you're using your sound card's analog output? If you're using a digital output, I would imagine you would want to keep it at 0dB (no gain and no attenuation). Am I right or am I missing something?
- scep12 14y ago
  Exactly. Digital volume is just smoke and mirrors. Turn it as high as you like - it's not going to distort. Any time you're going through a DA converter and controlling the volume after the conversion (at which point it's an analog manipulation) - which most OS-level volume controllers do - you should generally stay in the 50-75 range depending on the quality of you hardware. Some soundcards might break up at 25%, others might be okay at 100%. I find that 50% is usually safe, and any distortion at 75% is subtle and not offending.

mbell 14y ago

In most sound card designs I've seen there is a 'boost' switch on the output. In other words there is a toggle that enables a ~10dB boost on the output amplifier (or sometimes the DAC). The volume control is actually digital but when you hit a particular threshold the external boost is toggled on and digital volume adjusted to maintain a smooth level transition. If you keep going 'up' with the volume control your still changing the volume digital but you've now got an extra 10dB of gain on the output which can drive the output into clipping if the input signal is full range. EDIT: Just to add. I would be extremely surprised to see a sound card that isn't a full on pro model have true analog gain control. I've designed a couple products with such controls (for pre-amp gain, but a similar concept) and you need digitally controlled resistors to accomplish it. They are large, expensive and touchy to route without inducing noise. As an example: http://www.analog.com/en/digital-to-analog-converters/digital-potentiometers/ad5246/products/product.html http://www.analog.com/en/digital-to-analog-converters/digita...