Gareth Magennis wrote:

"Michael A. Terrell" wrote in message
...

Gareth Magennis wrote:

"William Sommerwerck" wrote in message ...

http://www.switchcraft.com/Drawings/14b_cd.pdf

That sort of stereo jack cannot perform speaker switching
on a hi-fi amplifier.

Sure it can. It's just not a good idea. You don't want to run the amp's
output
through such a "cheap 'n dirty" "switch".

You need ones that have a pair of independent contacts.

???

Presumably to switch a remote relay.

No. They switched a pair of resistors in line with the headphones to
reduce the drive. I recall a lot of 180 Ohm resistors on the back of
headphone jacks.

Yes, that would surely still rely on the switched headphone jack passing
the amplifiers power, or not, via its puny switch to the speakers.

What you really need is a pair of independent contacts in the headphone
socket that makes a circuit when a headphone jack is inserted.

This pair of contacts will then remotely switch the speakers off.

These sockets do actually exist.


They have been around since the '60s.