How to setup Virtual Audio Cable

Virtual Audio Cable (VAC) is a fantastic program that allows the re-routing of audio in software rather than having to use a second sound card and external leads for digital programs such as SkySweeper and Dream (DRM).

You can download the current version of VAC (4.08) from here.

There are several steps involved in getting VAC installed and working properly with PERSEUS. Below are the steps required.

• Install VAC as per the installation directions. If you have VAC installed, you must first uninstall that version before installing a new version.
• Once installed, set up a pair of VAC audio "cables" for use with PERSEUS by opening the VAC Control Panel.

• By default only one audio cable is defined. You will need to create two cables by changing the driver parameters to two cables then click SET and Restart. (i) Highlight the appropriate cable and change the values to match the figures shown below. (ii) In the "Ms per int" box enter a value between 1 and 20 ms. The lower the value, the smaller the VAC audio buffer. Depending on your computer you may have to adjust this value to prevent the audio from dropping out or "clicking" but you will soon find a happy medium between dropouts and latency.

• After completing all of the necessary changes, click on Set for each cable when completed.

• You will need two cables if you are routing audio out and back into PERSEUS. You only need one cable if you are only going to "see" what your decoding. Most digital decoder programs allow you to change the audio input source. Look for the VAC options in the dropdown list and choose the one you created in step 3. Note that some programs use the Windows Mixer. You will need to open the control panel and then sounds and then adjust the recording option to choose the right source to send audio from PERSEUS to your software.

(i) Cable 1/2, Max instances 20, MS per int 10(ii), SR range 11025..96000, BPS range 8..32, NC range 1..2, Stream fmt limit Cable range, Volume ctl Disabled.