MAC Autoformers?

Both the factory and a dealer said to stay away with Maggie's unless you go at least 600 watts.

@Johnto - must have missed an earlier post.  How does your post about Maggies fit in this thread?  I thought this thread was about autoformers.


BIF

With easily driven speakers ( impedance ), I much prefer the Mac amps without the autoformers. Same with OTL tube amps. But, let us be real. Many fine speakers are not easy to drive, and autoformers are there to keep the amplifier safe and sound ( pun intended ) and better match the speaker. Enjoy ! MrD.

08-03-2018 3:21pmWith easily driven speakers ( impedance ), I much prefer the Mac amps without the autoformers. Same with OTL tube amps.

https://i.pinimg.com/736x/56/c1/a3/56c1a3c6bb97f86a61c4144444b20508--emoji-faces-cartoon-faces.jpg

But, let us be real. Many fine speakers are not easy to drive, and autoformers are there to keep the amplifier safe and sound ( pun intended ) and better match the speaker. Enjoy ! MrD.

These speakers then should have different amps that can handle their loads.

Cheers George

Thanks George! Interesting read.

 I clicked on a link within the post that attempts to tout the benefits of an Autoformer; essentially better matching to speakers with different impedance values. Ie 4 ohm taps to 4 ohm speakers, etc. All well and good for “nominal impedance”.

But what about speakers with impedance swings all over the place, from 3 ohms to off the charts well at well over 20 ohms like 802D3s (nominally 8ohms). It’s swings like this that tax the best tube amps with their transformer outputs. How, exactly, do these impedance swings effect autoformers???

Are the electrical properties of autoformers similar enough to those of tube output transformers to cause similar issues when driving speakers with crazy impedance and phase curves?