Bookshelf speakers won't sound their best on a bookshelf, or a TV stand for that matter. Dedicated speaker stands are best for that. But other than that, I'm not sure I fully understand your concern with the vibrations of a larger speaker. Shake your TV too much? Any speaker with a decent woofer is going to generate vibrations with enough volume. Smaller woofer will shake nearly as much (for practical purposes) when at the same volume, as larger woofer. Maybe get a mini-monitor and cross the subs in at higher frequency. To limit shaking you would need to keep low frequencies away from any speaker with decent bass response. Good luck!

Speakers need to be properly placed within a room to achieve the best sound quality and create the magic that makes music come alive. Absent that starting point, it's simply a matter of further degrading the sound capabilities one after another with each additional compromise in sound optimization.

The vibration concerns are just one of many things that will be compromised and I'm not clear on why that issue in particular is of such importance. Monitor Audio makes fine speakers and are very good value...whichever you choose.

searchingforsound wrote:

Can anyone tell me the maximum dimensions for a standmouners placed on bookshelf (or TV bench)? My gut feeling says that the larger the standmounters are, the more vibrations (from the low frequency range) be transported to the bookshelf. Am I wrong here?

My plan is to place a pair of standmounters on a TV bench; combined with a subwoofer. However, I do not know if size matters. For example:
Is Monitor Audio Silver 2 too large?, and therefore aim for Monitor Audio Silver 1.

If you are going to use a subwoofer, the difference may not be a big deal. The Silver Series 1 is rated to go down to 45 Hz, and you probably don't want the larger speakers. That is low enough, since you can cross over to your sub at 50-60 Hz.

One thing that will help a lot is to put the speakers on the right material to provide isolation.

The best thing I have found is a sort of tacky waffle-foam plastic that is sold in RV parts stores to keep dishes etc. from sliding around in cabinets on the road.

It comes in a roll around 8 feet long and 10 inches wide, and pieces can be cut using scissors so they are just a bit smaller than the bottom of your speakers. A roll only costs $15 or less. Camping World is one supplier.

Another important thing is to have the front of the speaker sticking out slightly in front of the front of the shelf. If you don't do this, reflections and refraction from the shelf will be bad news. If you DO IT, you will avoid most of the problems of having them on a shelf.