Discovering How Amplifiers Dramatically Affect Loudspeaker Output - The fundamental point is that the way different amplifiers handle the varying impedances and current demands of real speakers is not a given. By a long shot.
www.theabsolutesound.com
Hmmmmm
The article title is misleading considering the speaker choice is the infamously difficult 801 D4 and has a known low impedance drop that makes it a difficult speaker, but still.
Also, it is also said that there were measured differences, but not a lot in the way of how they were conducted.
I dunno, maybe my article standards are too high.
That was a subjective review. There is a review in the UK Hi-Fi News with some measurements.
They drove them with a Classe amp.
This is the FR they show.
This is the Waterfall plot.
They recorded impedances as low as 3.4 ohms and phase angles negative to -71 degrees.
Those measurements are far worse than the ones I obtained from my late friend Phil's pair of 800 D3, which those speakers replace. The 800 D3s actually measured well, and were far from the most difficult drive.
The 801 D4s, if those Hi-Fi News measurements are reliable, are a disgrace at $34,000 per pair. I would certainly not be pleased with those measurements from a set of my speakers for sure.
To be honest though, if you are going to design a state of the art high output speaker in this day and age, the days of having it passive are OVER, period. They absolutely have to be active. I know I could not get the results I get in my theater, without having active elements. My former studio speakers designed in 1984, and now my rear backs were, and still are, a hybrid active/passive design. High powered low frequency low and high pass passive crossovers just do not, and can not cut it.
