Field-coil drivers, pros and cons. Relics of the past, or still relevant?

[mhardy6647]

HaHa, they shine beautifully blue.

I remember power supply setups by Thomas Mayer (aka VinylSavor) with such rectifiers, which would be better described as 'lighthouse'. I don't like them that way, as they make a lot of RF noise.

That they do. But they're good for high power requirements at high B+ and controlled voltage drop.
Lots of "hash" though -- but in this age of digital signal processing and SMPS, it's a drop in the bucket!

 

[fpitas]

That driver uses a simple field coil like the rest of them. Its not a bad driver but it certainly doesn't do 20Hz!

I'm sure the cone wiggles enthusiastically.

 

[atmasphere]

I'm sure the cone wiggles enthusiastically.

It does that at other frequencies too.

 

[ocinn]

Some PA midwoofers from18sound have a secondary stator coil which could be used in a likewise fashion.

Wow, these are some pretty major advantages. H3 practically disappears in the upper (800-2k) frequencies in a lot of the tests. IMD is way down. White Paper
I haven't heard it talked about much, seems ideal for small 2-way PA Monitor style speakers that need to do a lot of vocal frequencies.

 

[Newman]

Yes I have had those 18Sound midwoofers in my system since 2006, very cool tech.