I have always maintained the SPL meter and test tone method is superior to trial and error for any type of resonator, transducer, Brilliant Pebbles included. My directions on the page for Brilliant Pebbles include the SPL meter recommendation. Some applications for Brilliant Pebbles are straightforward and don’t require a SPL meter, but they might require experimentation. For example, sometimes the pebbles work on top of speaker cabinets, sometimes they don’t; sometimes they work next to small vacuum tubes, sometimes they don’t. Sometimes they work on connectors of IC, sometimes they don’t. There are several sizes of pebbles each with its own set of applications. That’s really what I meant by "some experimentation might be required."
But for room walls and room corners you want the resonators to go where they will do the most good, which is where the peak SPLs are located, including in the 3D space of the room. In room corners on the floor Large BrillIant Pebbles is usually very effective. But SPL meter and test tone sometimes reveals that the exact corner may not be the absolute best in some cases, the very best location might be say, 12" in one direction or the other from the corner. This is also true for Tube Traps.
So one can get good results by trial and error by locating *local maximums* but SPL meter + test tone can locate the *real maximums*. If a customer buys only 3 Brilliant Pebbles he might not require a SPL meter and test tone, but once the number of resonators becomes high using a better methodolgy than trial and error becomes important. Without a methodology like the SPL meter + test tone trying to find the ideal locations for resonators is like trying to solve N number of simultaneous equations in N+5 unknowns. In other words you're gonna need a super computer. Hel-loo!
