1/4" jacks--Open or closed circuit???

[consoleb]

I went to Radio Shack to buy 1/4" jacks to replace the mic and phono input jacks, also the speaker out jack on a Bogen CHB 10A PA head and they sell two types OPEN or CLOSED circuit. Which do I use? Also the mic input jack has three wires and the phono has one and is grounded to the chassis. Also the speaker out jack has three wires. Any ideas?

Thanks

Consoleb

[WaltC]

You got any pics of the Bogen showing the existing jacks? That'd help us a lot to figure out what to recommend.

Don't go by *anything* Radio Shack says....<G>

[doctorx]

Don't use RS jacks, they suck. Low grade Brand X crap. Get Switchcraft 12A jacks from Mouser.com.

Those jacks must have been added in a mod because the CHB-10A did not have quarter inch jacks for speaker outs. A picture would help.

[donnyjaguar]

What the Dr says. Most shorting jacks can be wired as open anyway. There are also jacks available which have elaborate switching which can be handy in musical instrument amps for switching circuitry.