Is it safe to run two sets of speakers on a Fisher 400 using a Passive Switch Box (with protection) like the one in the picture?
One set of speakers would be vintage Grundig's (see photo) from the 1960's that I believe are 6 ohms. The second set of speakers would be a passive Pioneer S-W33 Subwoofer (see photo) that is 8 ohms with duel speaker inputs.
If it is safe, do I run the Fisher 400 in 8 ohm or 4 ohm mode?
Thanks,
Mike