I'll be messing with this for a few months and will pop updates in here as I figure things out.

The Voicelive series is designed to be used with a Mic and an electric or acoustic GTR with MultiFX and Looping and even Cue mixes and Backing Tracks all in one (Backing tracks with the new "Extreme Model").

Voicelive 3 is selling for about $400 now.

To plug an Instrument into the Mic channel, you need to use a DI.
It is a combo 1/4"/XLR Jack, but will be noisy if you don't use a DI.
You have to go through and disable the Vocal oriented settings like noise gates/compressors/tone/Low end rolloffs on the Amp models.
You can use an XLR to 1/4" for the Vocal side output.
The Output level can be set to "Dynamic Mic" or Line Level.

The Vocal side doesn't offer the same Algorithms as the GTR side but there are plenty of Delays/Verbs/Chorus/Tremelo/Overdrive/a few Amps and then some weird things I might find use for later. Lot of SMART Harmonizers that use either a fixed key OR can track what is being played on the GTR side to set the key.

You get separate MultiFX for each side and you can feed each side to it's on Amp!
Tap tempo or preset tempo will automatically Sync up the FX on each side. Delays/Modulation/Choopers/Tremolo will all be in time.

HERE'S A GREAT THING:
When Looping, you can choose which input to use (or leave it set to both inputs by default).
When you overdub on a loop EVEN ON THE SAME "TRACK", the Outputs still stay separated.
Your Bass and Melody sides will continue to feed to their separate outputs.

You can have two Loops playing at the same time. They don't have to be the same length.
They can be free running, Quantized, or in 'smart' mode (there are YouTube videos explaining that).

I am currently using an added 6 Button Footswitch.
The first 3 switches are
(1) Loop Record/Play/Hold down for Redo
(2) Loop Stop/Erase
(3) Loop Undo
I will likely make (6) be a dedicated Tap Tempo and will experiment with the rest.

The 1/4" jack within the combo jack is a line level input, so running into it without a DI was never a viable option.

It's actually not true +4 Line level in or out.
So it does 'work' without a DI.
But depends upon your pickup impedance and output level

The impedance issue, which I mentioned in your "Looping" thread, is what I was referencing.

So you are not using the Voice live for vocals then..
The idea is to use the vocal channel for one side of the stick and the guitar channel for the other side.

Which side are you putting through the vocal channel?

I am thinking to get the Voicelive 3 Extreme because I want to play with a drum backing track and have it automate my effects. I sing so I would put my mic through the vocal side and I would put the melody side of my NS through the guitar effects/amps.
For my bass side I'm thinking about getting the Zoom MS-60B and plug it into the Aux or use an external mixer.

Just my thought. The unit looks amazing.

Very interesting idea to use the vocal processors for instruments.

I'm putting the Bass side through the Vocal chain.
Subtle compression and noise gate on the vocal side works well with the Bass.
And I prefer to have the Flashback and Hall of Fame algorithms available for the Melody side

You still have Chorus/Flange/Tremelo, bunch of different delays and reverbs and Amp models but you don't get the specific Corona Chorus Flashback and Hall Of Fame on the vocal side.

The big advantages you get from using the Voicelive on both sides is that your Effects are automatically in sync, your presets are recalled together and you have Synced looping.

APPARENTLY you can sync multiple Voicelive 3's together.

PS
There is a global Speaker Emulation on the GTR side

Nice!

I wish it has the vocal processor and two guitar inputs since I attempt to sing.