Will VoxDoubler work with other sound sources?
Yes, absolutely, VoxDoubler will work with anything you throw at it.
However, it is worth noting that VoxDoubler has been specifically designed for vocals. It intelligently analyzes the vocal track to create a realistic, new 'human' performance.
Why does the VoxDoubler use so much CPU?
Due to the real-time humanised pitch and timing changes that accurately model the phrasing and natural variances of a vocal performance, the VoxDoubler requires more CPU power than a standard EQ or Delay.
Additionally, the VoxDoubler has quite high latency by design. We need a relatively large amount of time in order to analyse the signal so that we can apply intelligent humanisation. Latency is also added so that the processing is free of audible artefacts, even with very low pitched voices. Reducing the CPU load of the VoxDoubler would dramatically decrease its sound quality.
It's not common that users will need to insert a VoxDoubler on every channel like you might do with an EQ, and therefore you shouldn't run into any problems with lag or corrupted audio. If you do, please consider freezing your track or increasing the buffer size.
Why is the Stereo Spread control greyed out on VoxDoubler Thicken?
The Stereo Spread control is only available on stereo channels. You can still use VoxDoubler Thicken on a mono channel, but the output will retain its mono state and so disable the Stereo Spread control. Some DAWs may still show the Stereo Spread control on a mono channel, but changes to the parameter will have no audible effect on the vocals.
Why is there no mono VoxDoubler Widen?
VoxDoubler Widen is not available as a mono insert. You may find that your DAW deals with this in one of three ways:
Your DAW may allow you to insert VoxDoubler Widen whilst changing the track to have a stereo output.
Your DAW may allow you to insert VoxDoubler Widen and incorrectly retain a mono output. This will not Widen the vocal.
Your DAW may hide VoxDoubler Widen from your choice of inserts on a mono channel.