I discovered a wolf tone on my 15 1/2" viola when playing the B, B flat (most noticeable) and C on the G string. It was easy to do. I got a little worried because I watched a video on how to do it. The first one was by a guy who actually likes this wolf tone eliminator, but he was so heavy on how you have to be cautious. I know the magnets on these are super strong and care is needed, but my gosh. He went on and on about how they can kill you. Many times. 

I received it Friday. I didn't get a chance to do it until this morning. Good grief, it is easy peasy. There were two options on how to do it.

One way was to drop the inside magnet with the modulator(?) into your viola so it will drop and fall to the side. Then take the top side magnet, felt side on viola surface, and drag it around and catch the inner magnet.

The other is to attach the inner magnet to the tool enclosed. The tool is just a long pipe cleaner. It is a little stiffer than they make them for crafting now. The current crafting pipe cleaners are really flimsy nowadays, this is a little sturdier.

The larger inner magnet with the modulator sticks to the pipe cleaner. You lower it into your F hole so half the surface top of the magnet is visible through the F hole. Then you place the top small magnet on top of the viola top, felt side against the viola, and drag it towards the inner magnet and they will attract each other. Then just pull the pipe cleaner out and adjust the Krentz to where you need it. Easy peasy. You have to adjust it to make the wolf tone as much toned down as possible, and not have the other strings affected, as much as possible. Basically, find a sweet spot.

I suspect, when strings are changed, the Krentz will be adjusted. The eliminator that came on my cello is on the G string itself, below the bridge, so it gets removed each time the strings are changed. It is not easy to put on. I might switch to the Krentz when I take it in for a check up in the spring and let the shop do it.

The wolf is gone and the other strings sound just fine. Took a while to find the spot.