The most dynamic speaker you've heard...

"Most dynamic home audio speakers I've heard were the Classic Audio Reproductions Hartsfields. "

With the field coil drivers I assume?

I heard one of the larger CAR speakers at Capital Audiofest this past July. Very impressive + gorgeous to look at! WOuld have liked to hear those in a larger room as well.

Has anyone heard Casta Acoustics? Would the model "A" specs fall into the realm of great dynamics compared to my Paradigm Signature S2's(V3)? I know the paradigms aren't horns but I am changing my home theatre set-up and I am running an integrated multi-channel hybrid tube and have researched the Casta's but haven't heard them. I would like a smaller speaker with great looks for the room. The Casta A's seem to fit what I'm looking for. Any have any other ideas? I have a dedicated SVS PB13 ultra calibrated with an As-EQ1 and might purchase another. My room is 14x20x8 ft ceiling. Thick carpet floor . Thx

Mapman,

I've always wanted to know what a "field coil driver" is, anyway. Can anybody enlighten me? Thanks.

A field coil driver uses an electromagnet (coil of wire carrying a current that creates a magnetic field) in place of the permanent magnet of a regular driver. This type of driver requires a power supply to energize the coil creating the magnetic field.

The field coil drivers I've heard were quite lively sounding (very dynamic). Old examples would include the Western Electric 555 driver, and modern examples include the woofer in the top line JM labs speakers and all of the drivers in the big Classic Audio speakers, and certain Feastrix full range drivers.

There are so many things that have to be right to get the most out of a field coil driver, particularly the power supply. I was really surprised how different these speakers sound with different power supplies.

I've always wanted to know what a "field coil driver" is, anyway. Can anybody enlighten me?

Instead of being generated by a permanent magnet, the magnetic field within which the voice coil moves (the voice coil being what conducts the audio signal) is generated by a DC current flowing in a different coil, referred to as the "field coil."

Field coil speakers were used in many radios of the late 1920's and the 1930's, before permanent magnet technology came of age. Those included high end radios manufactured by companies such as E. H. Scott (no relation to the hifi manufacturer H. H. Scott, who came later) and McMurdo Silver, which can be considered to be precursors of modern hifi systems.

I believe that the main theoretical advantage of a field coil driver is that there is less variation of the strength of its magnetic field as a result of vibration and perhaps other effects related to the audio signal.

Regards,
-- Al