Free ASIO driver -- ASIO4ALL --


Japanese version here.

listmarkWhat is ASIO??

ASIO(Audio Stream Input/Output) is a kind of audio drivers.
It provides a low-latency and high fidelity interface between a software application and a computer's sound card.

ASIO image

MME and DirectSound drivers are also kinds of audio drivers.
Then let's compare these latencies.

MME: over 100msec
DirectSound: over 50msec
ASIO: under 10msec

These values are under a general condition.
ASIO is superior to others.
When it's in good condition, ASIO can lessen latency shorter than 1msec.
If the latency is short enough, we can enjoy DTM without a delay.

Moreover, thanks to a short latency, we can avoid a jitter noise.
Jitter noise is a noise caused by time-base error.
If the latency is short, time-base error can be decreased.

Another good news is that audio streams don't pass through a kernel mixer when we use ASIO.
Kernel mixer helps to reduce a burden of sound players.
It plays a role of adjusting a sampling frequency and volumes.
If audio stream passes through it, the quality of the sound will be worsen because of its poor sampling converter.
It also causes a long latency.
MME and DirectSound use it, but ASIO not.
ASIO has potential for high-quality sound.

But cheap soundcards don't support ASIO.
It's a pity.


ASIO4ALL allows that whatever soundcards support ASIO.

The mechanism of ASIO4ALL is following.
Windows2000 and later have a path which data doesn't pass kernel mixer, called "kernel streaming".
It's a shortcut from a player to a soundcard, ASIO4ALL uses it.
But kernel streaming doesn't play a role of adjusting a sampling frequency and volumes.
ASIO4ALL provides these roles.
This is the same as ASIO.

ASIO4ALL - Universal ASIO Driver For WDM Audio

This is the ASIO4ALL official site.

Download ASIO4ALL and install it.
ASIO4ALL's setting window is following.
ASIO4ALL setting 1

Select a device which you want to output using ASIO from the "WDN Device List" and press the "Enable" button.
Then the device will become green and get a condition of Running.
Now you can use ASIO.

If you want further setting, press the "Advanced" button.

ASIO4ALL setting 2

listmarkplayers which can use ASIO


foobar2000's sound is like a digital amp, flat and clear. We can able to change sound by using components. I like this player.

foobar2000 official site


Winamp is a very famous audio player. We can able to change sound by using plugin.

Winamp official site

SoundPlayer Lilith

A Japanese player which is well revised for MP3. It's sound is like a vacuum tube.

Official Site (Japanese)

I use foobar2000 0.8.3.
I like the mpg123 input component and the ASIO output component by ota-chan.

listmark If you have a question or comment, please use BBS.
If BBS doen't satisfy your needs, give me a mail. (replace # by @)

Notice!! I don't take any responsibility for the trouble that can occur for this homepage. Please do at your own risk.