Reed Relays Vs Standard Relays

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I am considering using Reed Relays as opposed to Standard minature relays in my new preamp for swtiching the various input in my preamp.
Reed relays have a much higher insulation reistance of about 10,000 mega ohms compared with about 100 mega ohms for standard relays. This should improve crosstalk at audio frequencies vastly i hope. In doug self preamp design from his book he uses 4 pole switches effectively doubling the air gap between the switch contact to get a channel corrtalk at 10khz of 95db compare with 74db for 2 pole. A huge imrpvoement. So i thoughtthat using reed relays that are hermetically sealed and have huge insulation resistance will thus have lower stray capacitance between contacts. Has anyone ever used reed relays for low level line swtiching. I am cocerned about the magnetic field however. dont how this will affect a low level ac signal.
Any advice anyone??

Thanks
steevo
 
No a bad idea good reed relay's will work very well if you are concerned about channel separation you could consider RF type relay's they have very low parasitic capacitance and good isolation.
Teledyne is on example of such relays also look at Coto.
Steineker also makes some very good reed relay's.
The well made reed relays have a small screen around the coil to prevent noise coupling onto the contacts.
 
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Hi steevo,
I used reed relays in one of my own designs several years back & they were fine, however I much prefer an all electronic solution which is immune to ageing of contacts etc. My latest design uses MOS-FETS in a series shunt arrangement feeding into a virtual earth opamp. Signal isolation is truly impresive with no audible breakthrough even at full volume when fed with 10 volt pk/pk squarewave. Sorry about the hand drawn partial circuit, did'nt have P.C. at the time.
 
Sorry fpr holy thread revival!

I am also interested in the question what relays are best for input switching.

I just tried a reed relay and the (negative) sonic impact was very audible. I wanna try out Takamisawa RY and some no-names for comparison. Best switching so far were Silonex opto-couplers!
 
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