Looks like the VAC Preamp has a 8 volt output and the Audio Space AS 6M has an input sensitivity of 300 to 600mv ... seems the Pre my over drive the AS6M with it's 8 volt output or you won't be able to use much of the volume control on the VAC
This might be something else to take into account besides the PIN configuration that auxinput has brought up
You may want to consider a Pro Audio (XLR) to Consumer Audio (RCA) conversion box to knock down the voltage from the VAC to the AS6M
Here's one from Jenson ... http://www.jensen-transformers.com/product/pc-2xr/ ... a bit price at $329 but there are many that cost much less available on the internet