I wanted to continue to cut down on the noise output from the glowforge. The major issue I had was the vent holes on the bottom of the unit reflect sound right off of the table top and out the air gap between the unit and the table.
I initially tried putting up some semi sound reflective walls to see if it would help. It did help a little, but was more trouble than it was worth, and I didnt want to restrict air flow. The next step was to make an inset an-echoic like chamber for the glowforge to sit on. The table top is the exact width of the glowforge and has support beams to hold the feet that run width-wise. I left cutouts to allow for air to flow. The table top is about 6 inches deeper than the glowforge, so there is plenty of room for air to be pulled in through the back. This also means the noise has to travel al the way back there to get out, which doesnt happen =). If I staggered the slots between the sections it would have been even more effective.
Figured I would share in case any of you are trying to reduce the noise profile of your glowforge.