Bruce
Am using a 1hp dust collector from Woodworkers Source with the bags removed and it is very quiet and really SUCKS

Run it on the street side of my shop and never a problem with the neighbors.
Close off the top vent with plywood and attach an 90 deg 8" airduct to the bottom vent
Need to take a pic for you but this works really well.
Hook up to a 4" metal dryer vent hose
I have a 5gal paint bucket on the floor
On top of that I have a round SS office style trash can with the bottom cut out and resting on the bucket.
Attached the 4" vent hose with an Airduct fitting from Home Depot thru the side of the Trash can about a foot down from the top.
All the heavy stuff and most sparks stay in the trash can and land in the bucket...easy to clean.
Lighter dust gets sucked outside the shop
Going to add a "T" and a 90deg 4" pickup mounted towards the back of the belt under the grinder to catch the stuff that flies back
Confusing NAW it is simple and quiet
Pics maybe this weekend