Wild Burro Field Coils!

[ra7]

Excellent stuff Paul! Keep us posted. Very interested!

[Andrew Eckhardt]

Yeah the copper looks way cool. Polished will get a little hotter than well oxidized. Looking forward to seeing the production prices.

[natehansen66]

Sweet!! I've been getting into a 4-way design and I'm not much for fullrangers anymore, but this looks cool!!

But dude..........bring a cast frame fieldcoil-less betsy (without whizzer while I'm dreaming.....) and I'm in!

[pjanda1]

The frame is pretty isn't it? I don't think it makes sense for the regular Betsy/K. They are intended to offer great performance for the price, and the cast frame costs a bit more while doing next-to-nothing for the performance. In the cost structure of the Field Coil however, the additional cost is pretty small, and higher on the price spectrum, looks matter more. Sometimes I do wonder if I'd sell more Betsys and BetsyKs with that frame and a higher price, but I'd rather not do it!

Whizzer-less Betsys and BetsyKs (the WOW version, for With Out Whizzer) are always available as special order. Sometimes the wait is long, sometimes its only a couple of weeks. Cutting the whizzer off is pretty easy, but the whizzerless dustcap looks a little nicer than a jagged whizzer edge.

Paul
Wild Burro Audio Labs - DIY Full Range Speakers

[pjanda1]

For those not familiar with Dave Slagle's ventures in iron and copper, check out his blog. If you dig back a bit, you might notice some other notable field coils!

Paul
Wild Burro Audio Labs - DIY Full Range Speakers

[drspence]

Congratulations to both Paul and Dave. Please keep us all informed on availability and pricing.

[d to the g]

SWEET. congrats on making it happen!

[pjanda1]

Likewise! I've been meaning to send you a congratulatory note.

Paul
Wild Burro Audio Labs - DIY Full Range Speakers

[keantoken]

Have you determined whether the output impedance of the power supply affects the sound? After all the voicecoil and field coil work like a transformer and the field coil may behave differently if it has a high source impedance or low source impedance. One easy way is to use a LM337 CCS to power it instead of a voltage supply.

If the field coil is large enough to self-resonate, I wonder if it could cause oscillation for the amplifier?

Also, I keep wondering why manufacturers use resistive voicecoils when they could just use copper and an external resistor. This would make it impossible for the voicecoil to heat up and under fault conditions the resistor would fuse and protect the speaker. Have you thought about this Paul? Would it be cheaper to use normal copper for the voicecoil? It would also make current-drive experiments more convenient.

- keantoken

[nicoch58]

field coils sound better then alnico ,this is the report on supravox user as there is the same speakers with different magnet....

the simple answer probably is that magnetic is slow to react ,have a curve and add distorsions , just see the need of copper plate on ceramic ,problem that alnico don't have , Eddy current and so on...

great plus is changing the voltage change the t/s ie the sound....

@ Keantoken , Rod coleman reg is the best options

@pjanda1 , if have more info on price or so ..please PM

Ciao