[alsa-devel] What does 0dB refer to? (Logitech USB Speakers)

[James Courtier-Dutton]

Lee Revell wrote:
> On Sat, Apr 12, 2008 at 7:00 PM, John Rigg <aldev at sound-man.co.uk> wrote:
>   
>> On Sat, Apr 12, 2008 at 02:54:19PM -0700, stan wrote:
>>  > Is there a way to identify whether a card is pro or casual?  Number of
>>  > channels?  DACs?  Chipsets?
>>
>>  Good question. RME cards would usually fall in the "pro" category.
>>  With others, eg. some of the ice1712 cards, the same chip is used
>>  in cards with 2 to 8 analogue in/outs, so it's harder to categorise
>>  them. On reflection, it's probably easier for those of us who need
>>  everything muted every time to just disable or remove the init.d script.
>>  That's what I've done on my system.
>>     
>
> Same with the emu10k1 driver, it supports the consumer SBLive/Audigy
> series as well as the pro/semi-pro EMU stuff.
>
> Lee
>   
Are the output levels from the line out/speaker out connectors really 
any different between pro and cheap sound card?
For unbalanced outputs, the full scale should be the same for both types 
of sound card.
I think the main difference is the power amp that is normally outside 
the computer.
So, I would say that the loudness of the sound actually output to the 
speakers is not related to which sound card is being used. So, how can 
we set what the default volume will be when we have no idea which amp 
the user is using?
It seems to me that whatever way you look at this, A default value of 
"MUTE" is really the only safe level for all sound card types.


James