If you change the receiver setting to 4 Ohms, the voltage for the amplifier circuits is decreased. The amplifiers will clip sooner, robbing you of dynamics, soundstage, imaging and emotional impact. The 4 Ohm setting increases the risk of blowing your tweeters because clipping increases thermal stress in the tweeters. It does so because high frequency content is introduced from the harmonics that comprise the clipped signal. This high frequency content carries more energy than typical music and ignites the tweeters.
The reason receiver manufacturers have a 4 Ohm setting is so they can pass safety certification tests and stamp their receivers as 4 Ohm capable. They are indeed 4 Ohm capable but to a lower performance standard. If a receiver puts out 100W per channel into 8 Ohms, a 4 Ohm load would squeeze 200W out of it. But then, the heat sinks on most receivers would get too hot and the safety certifier would give it a fail. The 4 Ohm switch prevents this overheating by robbing the speaker of power. It's not inconceivable for a 4 Ohm speaker to sink only 40W max from a receiver rated 100W into 8 Ohms when set to 4 Ohms.
Practically, the 8 Ohm setting for a 4 Ohm speaker is of no concern unless you listen at very high levels. If so, the best thing to do is get an amp like an ADA. Any ADA doubles its output power when the load is decreased from 8 to 4 Ohms. But even if you don't, a well-designed receiver will self-protect. Of course if it's always self-protecting, you need an amp for sure.
My Onk has multiple modes of protection. It starts to compress the output and if I keep pushing it, it shuts the channel down. I like the ADA protection better. It doesn't try to fool you by compressing the output. It keeps going until it hits its limit and then gently shuts the channel off. It brings it back when the problem goes away.
Regarding speaker terminals for the OW, Axiom can make the speakers with terminals but not the brackets.
Last edited by Mojo; 12/15/20 06:10 AM.
