This message was posted by Greenwing on AmayaUsers.com. PLEASE DO NOT REPLY VIA EMAIL. Instead, respond to the thread on the WEBSITE by clicking here: http://www.amayausers.com/boards/cgi-bin/ultimatebb.cgi?/topic/1/1155.html#000003 Your explanation is very close to what is going on. Hoever there is noting to do with "Sound" It is everything to do with vibration and the tough ? tension force on the silver sensor bar. In tech training they showed us the electonic display the machine sees. alot like an EEG of a very active mind. and in that they can see where the thread interaction with the sensor is normally and when it is there with or without the interaction of the bobbin thread and when top thread is broken. It is also so sensitive that it can adjust the thread feed to keep the stitches perfect on the fly. It is all part of auto actifeed. =========================================================== The AmayaUsers Mailing List Website: http://www.amayausers.com Discussion Board: http://www.amayausers.com/boards Subscribe/Unsubscribe: http://www.amayausers.com/list ===========================================================