Musicians and those who just like improvised music should mark their calendars for the Flying Carpet Jam Sessions being held at ACU (Voorstraat 71) in Utrecht this year. These free sessions are held the first, third (and sometimes fifth) Tuesday of every month. The Flying Carpet is a new collection of musicians and generally creative people, putting together improvised music sessions along with art of any type.
The upcoming schedule, as it's planned so far, is available for perusal here. If you're interested in being a performer, and not just a listener, contact info@flying-carpet.nl. Make an evening of it, with a (vegetarian) meal at the ACU's café (from 18:00-21:00). The doors for the jam session events open at 21:15, with performances beginning at 21:30, and ending by 00:30.
