Alpine PDX-V9 Review

I sent some amps to Audio Science Review to be tested

Here is one of them

Alpine PDX-V9

I purchased it used a couple years ago for $200 locally via offerup.

https://www.audiosciencereview.com/f...plifier.28870/

Here is the birthsheet:

https://www.audiosciencereview.com/f...c-jpeg.171497/


Below is copied and pasted from ASR.

This is a review and detailed measurements of the Alpine PDX-V9 four channel amplifier plus subwoofer amp. It is on kind loan from a member and costs US $999.

Despite having one more channel than PDX-F6, The V9 is in the same box:
https://www.audiosciencereview.com/f...er-jpg.171449/


Let's see if it measures as well as the F6 did.

Alpine PDX-V9 Measurements
Here is our usual dashboard:
https://www.audiosciencereview.com/f...er-png.171451/


As with PDX-F6, there is some channel mismatch but not as much. Distortion though varies between the two with one channel weaker now. It lands the V9 slightly below the F6 as a result:

https://www.audiosciencereview.com/f...ew-png.171452/


This theme continues in SNR test:

https://www.audiosciencereview.com/f...er-png.171453/


As well as crosstalk:
https://www.audiosciencereview.com/f...er-png.171454/


Frequency response is improved though (although not in an audible way):

https://www.audiosciencereview.com/f...er-png.171455/


There was ringing above audio band with PDX-F6 which is gone now with V9.

Multitone shows slightly more distortion again:

https://www.audiosciencereview.com/f...er-png.171456/


But very respectable in grand scheme of things.

I had a hell of a time getting consistent power vs distortion curve. I tightened all the connections and messed around for a couple of hours and this is the best I could get:

https://www.audiosciencereview.com/f...er-png.171458/


It seems to be a power delivery issue. Same shows up with 8 ohm load:
https://www.audiosciencereview.com/f...er-png.171459/


And dramatically as we change the frequencies:
https://www.audiosciencereview.com/f...li-png.171460/


FFT spectrum shows more messiness than F6:

https://www.audiosciencereview.com/f...er-png.171462/


Power output was a bit higher though than F6:

https://www.audiosciencereview.com/f...er-png.171461/


Conclusions
It appears that in the process of adding another amplifier module with high power output for the sub, the overall performance is degraded some compared to last generation. What we see here is still quite good for a car audio amplifier but we were spoiled with how good with the PDX-F6.

I am going to recommend the Alpine PDX-V9, just not super enthusiastically.