Using subs as speaker stands ?

I have Tannoy PBM6.5 monitors on 12" stands on 10" subs in my HT system and it seems to be fine. You loose the flexibility of optimally positioning the subs in the room but I'm quite happy with the sound.

If you decide to try this, and I don't see any reason not to at least give it a go, you might compare the rubber isolation pods to using a sheet or Sorbothane, between the subs/monitors.

BAD idea. It sounds good for your space problems, but the resonances you'll transfer back and forth will have an adverse affect on your sound. You should put your monitors on killer stands as well as your subs. I hope you realize, with monitor speakers particularly, that your stands are an extension of your speaker. I don't know about the cost of the Tyler monitors, but proportion to your stands (quality wise) is extremely important. I have my monitor speakers on excellent stands and my sub, likewise. I can't help you with your space problem, but I really would hate to see you screw up your sound with that stacking idea. If you're interested in more about stands and resonances you can always email me. I consider stands as I would any other major component. The difference in sound quality, between poor and excellent stands is outstanding.

As Danner suggests, the ideal sub locations will likely be very different than your ideal speaker locations. As Warrenh suggests, stacking will not provide the same sound as separate stands (the bass will transfer through the rubber and the height is not ideal). For space saving purposes, you might choose to get the stands and place the subwoofers behind them. There is no direct transfer of bass waves and the subwoofers would be closer to the rear walls (where they generally sound better, but every subwoofer needs to be placed a bit differently). Good luck.