For guitar and organ, they're clear and sweet, until you pour on the gain, then the HV sags, dragging the field down with it, yielding a compressed effect you won't get with any digital rig. Both amps are still works in progress, though I played them quite a bit before I ripped into them. My only personal experience with EMs has just involved a couple of 12"s, a Jensen and a Rola that I'm playing with in a couple of DIY MI amps. The integrals' field supply interacted with the amplifier directly (for both good and bad), while the remotes acted more like a PM, and saved stringing 200-400 volt field wiring to all the speakers.
Back when EMs ruled, consumer gear had the field winding integral to the same power transformer that ran the rest of the system, while pro use dictated multiple remote field supplies.
I'm sure that yesterday's field coil drivers would benefit from today's power supplies. I always imagined cost being greater, but with $3500 compression drivers upon us all things are possible. I confess that my initial mention of cost was a red herring. Did Lansing or Altec ever build field coil horn drivers? I'm not in a financial position to pursue this now, but I am excited that other more able explorers might take this forward. Perhaps compression drivers might benefit as much or more. Most of all, the promise of even sweeter sound than otherwise possible would make the development of modern field coil drivers a desirable path of inquiry. Tweaking the transducer/cabinet combo at the turn of a knob, good lord. In the right hands, they sound like a diy dream come true.
I started this question with idle curiosity uppermost in my mind, but Scotty's revelations have increased my curiosity manyfold. Obviously field coils in the wrong hands could complicate audio beyond reason, but I am suffering from increasing interest now. You might look down at the quote in my digital signature to see how much I appreciate it. Thom, that is one hilarious take on clueless audiophiles. I've got to go befor I offend somone it's not my intention There would definetly be two schools of thought about that.
I see it now! The state of the art would be a little mg set the motor would run from a vfd and it would either be a dc generator or a polyphase set-up And what caps should you use to filter your supply or should it only be powered from batteries. Whether discrete diodes or a one piece bridge.
And the arguments over regulation whether you should use shunt or series regulation. Perhaps negative polarity through the early moon. I'm not serious but someone might me.With field coils today I can just envision the arguments about which polarit sounds best. You know you could go moving magnet while your at it.
I should think it should be cheaper, machines wind coils (I koow single crystle, oxygen free) and you wouldn't have to go through the magnetizing process and the hardening process but hey some people preach on TV some people sell audio. I know, a Linn was supposed to sound best if you put it on a chessboard supported by four upside down watertumblers. The only thing that could make them any different than pm would be that you could control mag strength and therefor efficiency so you could pay more for them because you thought you could correct what the engineer didn't understand. I know IF I get out his way, I want to visit him and hear what he has.įrom an audio buffs point of veiw, I have never heard FC,s and really want to simply because its something I never even knew about till fairly recently and is so scarce. I have asked Steve Schell about FC speaker sound, and he tells me its the most lucid and smooth, and relaxed, realistic sounding speaker you could want to hear.
I found it interesting, and possibly I will get back to actually doing it at some point. I spoke to them here in the States, and I asked for the Alnico versions, and they told me, NO, what you really want is the field coils! Apparently, and this is where it gets very interesting, you can vary the PS output voltage, and this changes the woofers parameters, allowing you to really fine tune the speaker to your taste, in a way you cannot do with any conventional driver.
What stopped me is that the A7,s need a bigger room than my living room, IMHO. I thought about taking an empty pair of A7 cabinets I have, and loading them with the supravox field coil 15. They tell me they are supposed to sound very good. You are welcome, I always look at Suparavox from time to time.