Is an Auralex Gramma a good investment for gigging bass guitar or a gimmick? Glynn

I have one and like it.  It is great for hard floors or berber carpets.  It doesn't make an audible difference (to me) on higher pile carpets.

It makes a big difference on big, boomy, hollow stages. Any time you need to decouple the cabinet from the floor, it does a good job. It doesn't do much on higher pile carpets because the carpet does the same thing.
 
I got mine after playing on a very flexible dock. For the second show, I got the Gramma and all of a sudden I could hear the bass, which had been lost to the dock flexing with the sound.
 
These days I don't use it all that much.

I don't know what it costs, but it's probably cheaper to get a chunk of shag carpet to do the job, then you also have something to mop up beer spills!
 
Tony

I did buy one and I have to say it seems to work well.
Also it rather neatly sets out my area on stage and a plug board sits nicely on it alongside the cabinet(s).
Glynn

I'm currently using mine for my PA in my studio.  Due to space constraints, I've had to get a little creative.  So I have my floor monitors creating a foundation, (and effectively being stored), against the middle of one of the long walls.  On top of the wedges, (which are on their sides), are my two JBL mains, splayed right and left.  On top of the mains is my Aurelex Gramma.  On top of that is my Mackie 808S powered mixer.  It seems to work quite well.
 
Bill, tgo