[franci2105]

Hi, someone knows the ohm impedance of the koss vintage models.
I need to know the ohm impedance of these models:

Koss ESP/6 -1968
Koss K6 - 1970
Koss K6A - 1971
Koss PRO4AA - 1970
Koss PRO4AAA - 1976

Thanks, regards. Francesco.

 

[WallofHooligans]

Esp should be 4-32ohm swing because of the nature of electrostatics. Not actually a good indicator of spl, again because of the electrostatic thing.
Dunno about k6 or k6A.
Pro4AA should be 250ish ohms, There are a few generations of these though, probably slightly different from each other.
Pro4AAA should be 220 ohms There are two generations of these iirc and another from the "Plus" line.

 

[franci2105]

Esp should be 4-32ohm swing because of the nature of electrostatics. Not actually a good indicator of spl, again because of the electrostatic thing.
Dunno about k6 or k6A.
Pro4AA should be 250ish ohms, There are a few generations of these though, probably slightly different from each other.
Pro4AAA should be 220 ohms There are two generations of these iirc and another from the "Plus" line.

Thanks. K6 and K6A remainig...

 

[WallofHooligans]

Why do you need the values btw?