If you use a toroid coil instead of an incased coil it would sound different.
Just to be clear, both are toroids. The reason it might sound different might be because the inductor can play an enormous role in how the output section switches and if there are problems with it, can cause spurious noise that can be many multiples of the switching frequency. Its not the sort of thing that you play with and not also subject the amp to extensive testing afterwards to make sure it doesn't block out channel 4 on the TV or the like... I might add that the output filter caps have to be chosen for low inductance characteristics and this relates very specifically to the way the leads are terminated in the device. If you replace those parts with something different that has greater inductance, RF noise is the likely result. The module has to meet EU Directives which are pretty strict in this regard- and those directives serve as a model for the UK and China and to a lessor extent, the US and Canada. If you don't meet them the consequences can be dire for a smaller company!
So here is my question. If these Purfi equipped amplifiers are so great why is it I returned my NAD M33 after 45 days because it sounded awful?
@jerryg123 To my understanding the Purifi modules are not offered with an input buffer/gain stage. To the best of my knowledge, the buyer is expected to install their own. This is one of the reasons you see such variable comments on Bruno's modules- some buyers know how to design a proper input circuit and apparently many do not. I don't know anything about the NAD in particular, never heard it. But I do know that the input circuit has to be really neutral and there are some pretty bad examples out there wired into Bruno's modules. So if I were you I would not take your experience with the NAD as particularly meaningful.
