I think this trick has been discussed before and there are many variations including not using exactly that preset.
The Air Balloon trick can make the lead vocal (or other tracks) "sit" in the mix and will add a bit of fullness and width without collapsing in mono playback.
It's basically a de-essed, equalized and M/S spreaded short reverb. It should be used in combination with your regular vocal reverb and/or delay.
Lead Vocal Stereo Effect (Air Balloon) Trick
1) Open a send from your already processed lead vocal to an available bus.
2) Insert a Space Designer reverb with the Small Spaces > Indoor Spaces > 0.08 ms Air Balloon preset. You need to insert this as the 2nd insert on the bus, leaving the first slot empty for now.
3) Set an appropriate amount of send from the vocal channel to the bus. Once set you should not change the send amount again but control the amount of the effect via the bus volume fader.
4) Insert a channel EQ with a 6dB/Oct HPF after the Space Designer. Roll off some low end, somewhere between 250 Hz and 1kHz. I often go for 500 - 750 Hz.
5) On the first slot you now insert a good de-esser plug-in. Or use the Logic Compressor with this de-esser preset:
Using the Logic Pro Compressor as a De-Esser
This will de-ess the input of the reverb but leaving the original vocal untouched of course. Adjust until you hear no sibilance in the reverb.
For a more dramatic stereo effect add this next step as the last step on the bus:
6) Insert a M/S spreader plug-in and spread to the max. Do not use a "fake" stereo spreader such as the Logic Stereo Spread plug-in. Instead use the Direction Mixer plug-in.
You can skip most of these instructions if you simply download and install the Bus Channel Strip below.
Audio Clips
In the mix
http://www.popmusic.dk/download/logi...ir-balloon.wav
Dry
http://www.popmusic.dk/download/logi...alloon/dry.wav
Processed with Air Balloon trick
http://www.popmusic.dk/download/logi.../processed.wav
The speak is 1 single mono track with the above effect on.
Bus Channel Strip Download Links | Audio Articles, Technical Tips, Download Presets
Download, unzip and place here:
Mac HD > Users > YourUserName > Library > Application Support > Logic > Channel Strip Settings > Bus > Balloon Vocal.cst
It will only show up on a bus, not on a normal audio or instrument channel.