Ah, papasteack, what you are asking is really how to make an easy load for the amplifier! 😀
Amplifiers hate highly reactive loads at low impedance. This is because they need huge fast current changes to keep up with the demands. At high frequencies they can even go into instability and oscillation.
A powerful speaker motor on a speaker running in reflex is about as demanding as it gets at low frequencies. With Class D (aka Class T IIRC), there is something to be said for keeping the high frequency impedance resistive and low as well. This is because Class D's chopping action needs to dump the ultrasonics generated by its very nature.
The theory is that transistor amplifiers maintain a low output impedance (high damping factor) and grip on the driver. In practise it is slightly load dependent. You are right in thinking a fairly flat impedance, a high impedance around 8 ohms, and low phase shift in the filter are all good things in the real world. Harbeth, for instance, are proud of the easy load their speakers present to the amp.
Amplifiers hate highly reactive loads at low impedance. This is because they need huge fast current changes to keep up with the demands. At high frequencies they can even go into instability and oscillation.
A powerful speaker motor on a speaker running in reflex is about as demanding as it gets at low frequencies. With Class D (aka Class T IIRC), there is something to be said for keeping the high frequency impedance resistive and low as well. This is because Class D's chopping action needs to dump the ultrasonics generated by its very nature.
The theory is that transistor amplifiers maintain a low output impedance (high damping factor) and grip on the driver. In practise it is slightly load dependent. You are right in thinking a fairly flat impedance, a high impedance around 8 ohms, and low phase shift in the filter are all good things in the real world. Harbeth, for instance, are proud of the easy load their speakers present to the amp.
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