The board you show has got an output filter (limited in capacity) and it works well with ordinary speakers. You can find it at even better prices.
The problem with class D amplifiers is they use the load (the speaker) to damp the resonance of the output filter (look for "ddapkus" postings). Without having any experience with electrostatics, I could fear that the transformer does not provide an impedance similar to an electrodynamic speaker.
You better ask the experts on electrostatic speakers about their loading impedance at the input and their experience on class D amplifiers with electrostatic speakers.
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Thanks FauxFrench.
What I know about the impedance on the electrostatic is that in a situation with an inferiour design of the stators, the impedance is almost 0 ohm at high frequencies.
I've had this a few times with some stators without proper segmentation of the wires. I did only use 4 wires in the center wire for the full range now, and it's much better know for the amp.
I did add a resistance of 333k ohm between the 20 - 4 - 20 wires now. So I think this will play also good on class D amps now.
I do prefer at least 250watt of Class D amp to get good dynamics on a full range ESL.
What I know about the impedance on the electrostatic is that in a situation with an inferiour design of the stators, the impedance is almost 0 ohm at high frequencies.
I've had this a few times with some stators without proper segmentation of the wires. I did only use 4 wires in the center wire for the full range now, and it's much better know for the amp.
I did add a resistance of 333k ohm between the 20 - 4 - 20 wires now. So I think this will play also good on class D amps now.
I do prefer at least 250watt of Class D amp to get good dynamics on a full range ESL.
You know far more about electrostatic speakers than I do. Recalling from the past, electrostatic speakers (Quad) may have a very low impedance at certain frequencies. So, I consulted the net in order to see some loading curves - what a horror. The impedance varies enormously with frequency and the impedance may go very low.
The small TDA8932B board you showed will neither deliver the power you want, nor like 2 Ohm impedance. Look for a class D amplifier stated to be able to work also with 2 Ohm loads.
Good luck with the project.
The small TDA8932B board you showed will neither deliver the power you want, nor like 2 Ohm impedance. Look for a class D amplifier stated to be able to work also with 2 Ohm loads.
Good luck with the project.
It would be interesting to design the output filter of a class D to match the step up transformer given it's built-in inductance. And possibly include feedback around the xformer to compensate for at least its DC resistance, if there's stability to do so, but that's probably beyond the scope of what's being asked in this thread.
We have a pretty long-running thread on the TI TPA325x EVM boards, which are I believe still available for a screaming good deal. The 3255 would accommodate your needs, I believe.
We have a pretty long-running thread on the TI TPA325x EVM boards, which are I believe still available for a screaming good deal. The 3255 would accommodate your needs, I believe.
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