On Mon, Sep 10, 2012 at 10:23 AM, Harold Hallikainen wrote: > I'd probably put the DC block capacitors before the relays and then have > resistors to ground. Having the resistors across the relay contacts will > give you crosstalk or poor off channel attenuation. On the relays, I'd us= e > either reed relays are bifurcated gold crosspoint relays. While mechanica= l > relays give you the best attenuation, least loss, and best distortion, > solid state switches are getting pretty good. We're currently using DG452 > for line level analog audio switching. > > Harold Harold, I think you're right that the DC blocking cap should go before the contact. I'm not sure why I had it after the relay. I just checked out the DG452 and it does look good. It doesn't seem like it would be a major cost savings over a relay except that it's easier to assemble. I'll probably switch over to that chip. The last time I looked, which was a couple years ago and didn't involve an exhaustive search, I found it difficult to locate analog switch ICs that allowed a bipolar signal. Or perhaps I'm just thinking of potentiometer ICs. Thanks, --=20 Martin K. --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .