No....the switch on on the output side of the amplifier, one audio source. There is a delay in the audio...ie....it sends out the audio....then shuts off. Once the patrons move to the next spot it turns on the cd player again and switches to the next speaker. Michael Rigby-Jones wrote: >-----Original Message----- >From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] >Sent: 09 May 2006 14:48 >To: Microcontroller discussion list - Public. >Subject: RE: [EE] switching audio signals 50W > > >The amplifier is already installed. Essentially its for a >science display unit, where a single audio signal is sent to >this multi-channel amplifier. Sensors pick up when the person >is walking along, so rather than blasting out audio all along >the walkway, it "follows" the user, switching it from one >speaker to the next. > > Yes..there are issues. The exhibit is designed so that the >viewer will be single or at least grouped together so no >worries about having to turn on the speaker 3 stations >behind..etc. The other issue, and the client is aware, is the >possible "popping" of the speakers when they are turned on and >off. But he will live with that. > > So, relays it is. And yes there is of course, a PIC driving >the relays and watching the sensors. Hang on...is the signal to be switched going *into* the power amps rather than the speaker level outputs? If so that opens up a whole bunch of other non-relay opportunities. You could also fade in/out the different speakers to prevents popping etc. Regards Mike ======================================================================= This e-mail is intended for the person it is addressed to only. The information contained in it may be confidential and/or protected by law. If you are not the intended recipient of this message, you must not make any use of this information, or copy or show it to any person. Please contact us immediately to tell us that you have received this e-mail, and return the original to us. Any use, forwarding, printing or copying of this message is strictly prohibited. No part of this message can be considered a request for goods or services. ======================================================================= -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist --------------------------------- Talk is cheap. Use Yahoo! Messenger to make PC-to-Phone calls. Great rates starting at 1¢/min. -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist