Just the past few days I have upped my clarinet practice quite considerably to try to improve a particular piece. It has a lot of high notes in it and very little time to rest in between demanding long phrases.

I have noticed a strange sensation in my throat. A feeling of constriction - is there some way in which wind instruments place demands on the throat and what can be done to improve technique and eliminate such sensations if so?

Whenever I read things like this, my immediate first thought is : are you stopping the airflow with your throat to articulate? If you are, this is almost certainly the cause of your discomfort, and you then need to ensure you use your tongue to articulate.

Thanks for that. I will make a conscious effort to articulate using the tongue. I was also interested in the lung capacity thread. Lots of good advice there so thanks for that.

Try yawning widely (without the clarinet) and then try and have the same yawning sensation while you are playing.

You could also try looking for a thread I started in the viva voice forum several months ago called something like "singing and whistling" in which Rosfrog has all sorts of helpful ideas about getting (and keeping) an open throat.

No problem.

I'm assuming you articulate using your throat/airflow, judging by your post, which isn't the way to go. Experiment using different parts of your tongue on different parts of the reed, and see what suits you best.