I have a Bunn VPR commercial brewer, and I have watched the videos you have posted on You-tube regarding brew times and ratios.
I was wondering, what technique I
could use if I only wanted to brew half a pot
on such a machine? Particularly, if I add enough grounds for half a pot and pour only half a pot of water
into the machine, the ratio would be correct but the brew time will be half the optimal time for a complete brew as the water still flows
out at the same rate.
Brewing a lesser volume than full always has
compromises. You did not mention if you are grinding on demand or using pre-ground coffee. If grinding on demand you have the option to grind
slightly finer to compensate for the faster brew time. When using a pre-ground coffee a slightly higher dose weight will for the half brew
may satisfy your taste in the final cup..
Remember it's all about the cup and making
a brew you like. Experiment!