- Joined
- Jun 27, 2016
- Messages
- 146
- Tagline
- ---
As was mentioned, those speakers will dip down pretty low impedance wise at some frequencies. The lower the impedance, the closer to a dead short so the amp's protection circuit is doing exactly what it's supposed to do. This was the case initially with a Double Advent system I had in the mid 70's. For optimum performance they were to be wired in parallel and although each speaker cabinet was rated at 8 ohms, they were actually closer to a nominal 6 ohms so in parallel, the amp saw 3 ohms on occasion. My "dealer" at the time let me take equipment home to try out over a weekend and several power amps could not tolerate impedance that low and shut down. As you are experiencing, this manifested when the volume was turned up but low level listening was fine. I lived in a house back then where loud music was de rigeur and it took several auditions to find an amp I could afford that would not shut down. Early on, the service department of the shop I bought the Advents from suggested a load resistor on each speaker to bring up the impedance but that made me blow tweeters.