REVIEW: Surprised by SQ of Class-D Full Range amps!! Alpine PDX, JL Audio, Etc

[wenn_du_weinst 10+ year member]

this review surprises me, these amps got a less then favorable review on diyma. Maybe it was older model.

 

[SikFly 10+ year member]

Class D amplifiers are notorious for causing RFI/EMI issues, but that never mattered to me because I don't listen to the radio. Unfortunately, EMI can be a huge issue amp to amp and nearly impossible to solve. For example, I witnessed a setup where one class d amplifier was under the seat and the other was in the trunk. The class d amplifier under the seat made noise while the class d sub amp in the trunk was just powered up. Power off the trunk amp, no more noise. Replace the amp under the seat with a class ab amplifier, no more noise. I wonder if that is what rc10mike's problem was?

i had that problem with my old RF 600.1 BD. Also, the radio was impossible to listen to. But i found some Class d amps don't do that. i purchased an MTX Elite class d amp cause they advertised no interference and did great for both radio and other amps.

I now got an XD 600/1 amp and no interference issues either. Radio comes in clear and no noise from my other amp.

Originally i had a maxxbass too when i had that RF installed, noise was bad from it so i removed it first, so i now wonder if its noise issues was also related to that RF.

 

[cleansoundzz 10+ year member]

I Alpine M12 when I initially installed it in the truck was running with an Arc Audio KS 300.4 had a terrible pop off noise when I turned off the truck. Once I installed my F4 on the other side that issue went away. I noticed sometimes when installing amps from 2 different brands that issues always came up in my system. This is one reason why I like my sub amps and mids and high amps to have matching brands.

 

[Shinju 10+ year member]

My PDX amplifiers are far apart and I have no noise issues. Once I get my False floor amp rack done all 3 will be next to each other I will report back and tell you all if I get any noise issue.

I remember Trypath amplifiers having noise issues with FM radio and other non class T amplifiers installed near them.

 

[RAM_Designs 5,000+ posts]

I heard the original PDX's and wasn't impressed at all. I like the Eclipse XA4000 though, as well as the new JL amps out. Space really isn't an issue for me, so I'd rather have some good ol' a/b amps, even on my sub since I don't need a ton of power.