Rather decent looking field coil bass drive unit from Queenway of China. Not exactly cheap though!
https://nl.aliexpress.com/item/Lijn-...OrigTitle=true
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Rather decent looking field coil bass drive unit from Queenway of China. Not exactly cheap though!
https://nl.aliexpress.com/item/Lijn-...OrigTitle=true
戈登贝内特
^^^Yeah, exactly what he said! Uh...what was it that you said there? :scratch:
There is a 12" Magnavox field coil speaker in a very very old radio here.
Is there any advantage of field coil units?
Probably need a couple of these to drive them properly:
https://nl.aliexpress.com/item/Line-....13339.90158.0
That one has bothered me for some time. I assume it is historic, as permanent magnets then were not powerful enough (i.e. could not produce sufficient flux density).
However the power supply has to be very well smoothed, otherwise any residual mains hum would modulate the audio signal. Traditionally they ran off 100V and consumed a fair bit of power.
The only advantage of field coils I can see is that you can vary the energising current, and hence the damping.