For sale is a used Stax SR-84 Electret system, which was introduced in 1982, and includes:
1. Stax SR-80 Electret headphones
2. Stax SRD-4 Adapter, which allows you to power the headphones with a speaker amp.
I am asking $99 OBO, which includes shipping in the U.S.
These are both in very good condition except for:
1. A couple of minor scratches on the SRD-4 adapter.
2. The foam that was originally underneath the pleather earpads of the SR-80 headphones had disintegrated by the time I bought these used. I have replaced said foam with some visco-elastic foam I had on hand. The actual pleather is still in very good condition.
These are supraural headphones with a pleather covered adjustable headband. The headphones are in fine working order, as is the adapter. Note that these can also be powered by any of the Stax amps, past or present.