Hi,
I'd like to replace the inductors on a TDA7492 with toroidals. The amp is mounting 330uH inductors, what are best for using with 4.6ohm full range drivers? is 220uH a better choice?
Thanks!
I'd like to replace the inductors on a TDA7492 with toroidals. The amp is mounting 330uH inductors, what are best for using with 4.6ohm full range drivers? is 220uH a better choice?
Thanks!
You have misread "330" on the inductors as "330uH", inductors normally use resistor-style coding, "330" means 33 x 10^0, or just 33uH.
For instance "101" on an inductor means 100uH, "331" means 330uH, "100" means 10uH.
For 5 ohms load or so I'd try 22uH and 330nF caps. That's somewhere between the 4 and 6 ohm recommendations.
For use in a filter gapped inductors are much better as they are more resistant to saturation and stabler in value. However they radiate more magnetic field and need to be spaced apart from each other (cheap class D boards skimp on this!). Toroidals are not the best choice for class D output filters unless iron-dust type which count as a distributed magnetic gap.
Choosing inductors is a complex business there are many factors to consider.
For instance "101" on an inductor means 100uH, "331" means 330uH, "100" means 10uH.
For 5 ohms load or so I'd try 22uH and 330nF caps. That's somewhere between the 4 and 6 ohm recommendations.
For use in a filter gapped inductors are much better as they are more resistant to saturation and stabler in value. However they radiate more magnetic field and need to be spaced apart from each other (cheap class D boards skimp on this!). Toroidals are not the best choice for class D output filters unless iron-dust type which count as a distributed magnetic gap.
Choosing inductors is a complex business there are many factors to consider.
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