Owner`s manual

Appendix C: Multi-client audio FAQ

Q: What is “Multi-client audio”?

Multi-client audio is a feature that lets you use different inputs and outputs on

your Echo card with different applications at the same time. This way, you can

use several different audio applications with just one Echo card. Otherwise, you

would have to use a different audio device for each audio application.

For example, suppose you own both Cubase VST (multitrack audio) and Reality

(software synthesizer). You can now set Cubase VST to play out through outputs

1 through 6, and set Reality to play out through outputs 7 and 8. In previous Echo

card drivers, you had to choose between one software program and the other.

Note that all of the various interfaces are multi-client. You could have an ASIO

application, a wave application, and a DirectSound application all running at the

same time. It's very flexible.

If you want to use multi-client audio, you need to enable it in the main driver

properties page. See the section entitled “Additional Configuration Settings” in

this manual.

Note:

Multiclient audio is always enabled with the WDM driver.

Q: So what's the catch?

The catch is this: all the apps using the Echo card at the same time must be set at

the same sample rate. This is a limitation of the hardware.

Say that you didn't follow this rule in the previous example. Say that you initially

had Cubase VST and Reality set up for 44.1 kHz- so far, so good. Then you load a

song into Cubase that is set up for 48 kHz. Cubase will change the sample rate of

the hardware. Unfortunately, this means that Reality is now also coming out at 48

kHz, so all the sounds played out of Reality will sound higher in pitch.

If you're planning to use multi-client audio, the best thing you can do is to sit

down and plan it out. Make a chart of each input and output on the Echo card and

write down what application is going to use what input or output. Go through all

the applications you plan to use this way and set them all up for the same sample

rate and set up their inputs and outputs correctly.

You should also turn off your system sounds. Most system sounds tend to be at 11

kHz or 22 kHz. Imagine that you're recording the best guitar solo of your life and

someone clicks on something on the screen. The 22 kHz system sound will play