Confusion about DSP Type

I want to add some DSP types in my code,but I do not know how it plays.
eg.When I add EQ and LOWPASS DSPtype,then how it plays? First Process EQ data, and base on EQ effect to process lowpass type ,or not?
Anyone can help me?

When you add a DSP to a channel, you also need to specify an index offset to add this DSP unit at in the DSP chain. This determines the order that the DSP’s are processed in.

Thank you very much.I have another question,when I load DSP Plugin such as fmod_noise.dll and fmod_gain.dll to play a song,there is no voice at all.Anything wrong with thes dlls?

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