Hi! I asked the seller before installing the unit and he said I can use the circuit on the quadlock. It worked for a month. I sent it back to China and received a new one. The answer I received was that the mainboard had a defect. The second one worked fine but I sold it because it had a bzzzzzz sound when there was no music playing. I replaced it with a pioneer D1004,no dsp but 4x50w rms for my louder speakers. This one has no static sound and I am happy.

@@andymazilescu6479 oh that's nice I used pioneer units, speakers, and amplifiers before . But they become outdated sadly.. anyway I'm using isudar Chinese DSP and an underseat amplifier with 4 speakers as a package for a year now. No issues except The difficulty with using the DSP interface! I must use an app on my phone, I can't adjust it from my head unit. Other than that, all good and it works perfectly . Deep sound Clear tewters Enough bass but not hard. If you are interested to test them Look for ISUDAR CLASS D DSP, AMPLIFIER SPEAKERS PACKAGE. good luck 🙏👍