AKG 701Q bass Mod...

I just got a pair of these off of Craigslist NY for a song (LOL) and have looked at the "bass mod" videos placed on the internet that people are doing because they feel the bass on them is lacking. I have come up with a simpler modification that one can try if they are interested. Place a layer or two of tape on the outside of the ear cups, covering the center portion, thereby making that portion of the cups airtight. I used blue painter's tape, since it comes off easily and leaves no trace, making this modification easily reversible and does not affect the resale value in any way. If anyone else tries this I would love to hear their impressions. Thanks.