I have a Vocal Track
I have a bus - getting from vocal

, I have applied Delay on that bus.
Both tracks output to Master.
 
I am trying to get the delay output only when main vocal completes a phrase and suppress the delay when main vocal starts.
Please guide.
Thanks & Regards
SG

        
        

        

            
        
    

Normally I automate the delay in situations like this. Usually there is some sort of 'input' value which you can switch off most of the time and just raise the value at the end of a phrase. You can probably manually draw in the envelope yourself in an automation lane. You may need to automate the delay output level (or the bus output level) as well if the delay sometimes repeats for too long.
 
Some delays come with built in 'ducking' capability and while that does help if used live, I don't think it's an adequate replacement for manually automating the input and output to the delay when working in a DAW.

Split the clip, and put the vocal clip on a new track. this way it only delays the vocal you want. of course you need to put the sends on the vocal track.  just onther way to skin the a cat.
   

Volume automation on the bus. You'll want to bring the delay in gradually, over a quarter- to a half-second, to avoid an abrupt change. It's the kind of thing you want to draw in by hand and audition, rather than recording the automation.
 
Check to make sure the delay you're using doesn't have a wet/dry mix knob, because if it does you can just automate that control, eliminating the need for a separate bus.

Much easier than what I was going to suggest, lol.

If you mean effect without automation, put a side-chain compressor after delay, and set up send from vocal track to this compressor's side-chain input, set it to heavy compression (without gain up).

or split the clip and insert the effect on the clip(s) you want the delay on. No need to place the on a separate track unless this helps you manage this.

Situations like that... I honestly use the old but still good Sonitus Delay on the bus... Turn it to 100% wet mix so only thing heard is the pure echoes.. Then automate in at the end of ur phrases.. i regularly do this things with reverbs as well to help enhance the end of a "Bar" as we say in hip-hop/rap.
 
Also in the settings... sry if im insulting intelligence, u prolly dont need the default like 50 feedback. its good to tweak those settings a bit.

Adq
If you mean effect without automation, put a side-chain compressor after delay, and set up send from vocal track to this compressor's side-chain input, set it to heavy compression (without gain up).

 
Yeah, I was going to suggest that!

Can you please guide on side-chaining ? [I mean Screen shot if possible]
I am asking too much help !!