I'm with TDM and Grandad on this one - changing tone of voice is often very effective.

With a young nipping pup I would normally start trying the high pitched yelp, but otherwise my "correction" voice is a deep, growly voice. As opposed to the higher, much more upbeat voice used for encouragement and praise.

My personal feeling on corrections:

I have no issue with corrections in the form on P- (removal of reward) and this is what I use most often.

I am not totally against P+ corrections, but personally I do not use anything that will cause pain or fear. Hence I will give a sharp look or a verbal correction. I even occassionally use a startle (a squirt of water for example). However, the exact nature of the correction would depend on the need to stop the behaviour quickly, and the dog in question. I wouldn't use a noise to startle a noise sensitive dog for example. IMO, a startle / interuptor should be something that is not of itself aversive but simply makes the dog jump. (like someone sneaking and behind you and saying "boo!")

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