Sound Volume in Dosbox (mixer master 10:10)

[Simon]

Dosbox too loud?

mixer master 10:10

Execute this line within Dosbox before you run your game in Dosbox.

E.g., put it in your configuration's autoexec section (see the bottom of dosbox.conf), or type it at the prompt before your game.

What it means

"master" means Dosbox's master mixing device. This affects all sound sources in Dosbox, e.g., Sound Blaster, PC Speaker, ...

"10:10": The two numbers separated by a colon define the two volumes for the two audio channels (left and right). Practically always, you want to put two equal numbers separated by a colon. But you have the option to put different numbers.

You can give each number in one of two formats:

• You can give a number unadorned, then Dosbox interprets the number as a percentage (popular but nonsensical), where 100 is full scale (the sensible maximum without clipping) and 0 is silence.
  
• Or you can write d- in front of the number, then Dosbox interprets your number as negative decibels from full scale. Here, d-0 is full scale, and d-inf is silence.
  

Fractional values are allowed: mixer master 5.5:5.5 is a volume between 5:5 and 6:6, even though Dosbox will print it rounded to integer. You can put several digits after the decimal point, e.g.: mixer master 1.23:1.23

The percentages really mean the following:

mixer master 100:100	means  mixer master d-0:d-0	(full scale)
mixer master 10:10	means  mixer master d-20:d-20	(a nice volume)
mixer master 1:1	means  mixer master d-40:d-40	(pretty quiet)
mixer master 0.1:0.1	means  mixer master d-60:d-60	(almost silent)
mixer master 0:0	means  mixer master d-inf:d-inf	(absolutely silent)

For −x dBFS, percent(−x) = 100 ⋅ 10^(−x ÷ 20).

For p percent, dBFS(p) = 20 log₁₀(p ÷ 100).

Miscellana

Type mixer without any arguments to see the current volume.

Put /noshow after the command to suppress Dosbox's immediate printing of the new volume levels, e.g.: mixer master 10:10 /noshow

You can choose volumes louder than full scale, e.g: mixer master 120:120 Or: mixer master d+2:d+2 But these volumes clip. You should first consider other means outside Dosbox to make the overall volume louder.

Sources

• Own experimentation in Dosbox 0.74-3
• Topic "mixer command" on vogons.org
  

-- Simon