I'm not trying to be a buzz kill here, as I really do enjoy the work and design that's gone into the jade build, but 2 vero 29s so close to each other and driven that hard is a death weapon, not a grow lamp.
From my experience with vero 29, I had 6 of them at 1050mA and still had to keep them far from the canopy, and got poor distribution. I couldn't imagine how 2 at 2.1A closer together than any of my 6 were together isn't just going to burn the one plant it's shining on down if it's not at least 2 feet away from the canopy. Even then, the light spread would be relatively poor (50% at 60 degrees).
Good questions .
Let me think for a moment ...
( Well ..I dunno for his set up ,but all the set ups under those lights perform very good to great ...
Hmmm..At least to words spoken to you ,from those light owners ...
Now ...How's that possible ? Hmmm..
Still... those 2x veros ,so close together ,are the same death weapon ,like a HPS is ...
Under a reflector and through a glass tube ,HPS has just a tad better light
dispersion ...
With the cost of absorption ...Outer glass tube + refelector ..
But both light distribution patterns are close enough ....
Of both the average HPS system and those dual COB lights .....
And yes ..
At 2.1 A ,this light should have a distance of at least 40 cm from plants ....
But then this is 'full throttle' ...
As for light distribution ...
You might want to check on light power distribution of most HID reflectors out there ..
The ones offering better light distribution than those two Vero29 ,are at the $600-700 and above range..
Remember ?
we used to grow with worse light 'patterns' ...
I 'm not in the position to know ,what went wrong with your plants ...
Others ,around here ,drive their COBS ( i.e. CXA3070 series has almost exact same light distribution with VERO29 ...),
more than 1000 mA ...And more than six at few cases ...
Nothing seems to be wrong ...
On the contrary ...
..
Time for me to go to sleep ...
Enough with 'thinking' ..
Sometimes gets really tiring ....
Natta ...