Current limit onset definition?

Atma, did you mean 40? or 60?
I appreciate you have genuine knowledge on these things.

Ack, confused, there are no newer DMA180's that I'm aware of.
What do you mean?

I'm still not clear how Spectral is defining amps
if in fact it outputs only 683 watts into 2 ohms.

Briefly. I understand a 15 amp circuit at 120 voltd is 1800 watts available to the amp. How does this factor in?

Thanks very much Al. On my DMA180 the fuses are specified as 8 amp for 100 and 120 volts. 4 for 220.
I bought my Spectral and MIT gear based on discussions with MICHEAL PERCY, who sells components via his website. I am reminded that he was especially knowledgeable and helpful. From my experience one can be very confident in dealing with Michael. I would not hesitate to send a bank draft or money order-with my order. He is a reliable gentleman.

Atma, I'm even more confused, sorry. What does the 40 amp have to do with?

Ralph,(Atmasphere I think). Why square the 90?
I see nothing about squaring in the power formula.

Why do you say 600 watt output section?

Thx Al. I'll look into this.