Thursday, August 18, 2011

RF Punch 150HD vs PG MS-275 - Part 2 - Power Output Tests

As promised, here is the update of the comparison between the Rockford Fosgate Punch 150HD and Phoenix Gold MS-275....I call it "Part 2 - Power Output Test"

Before I get started, I wanted to stress the importance of changing out the capacitors if you have a Phoenix Gold MS or MPS series amp. My MS-275 is in MINT condition and appears to have little use, however the caps still showed signs of leaking. In order to prevent a blown up amp and possibly starting a fire, I sent the amp to Envision Electronics ( for the capacitor replacement. Although they make no mention of amplifier repair, the owner, Aaron Hammet has an extensive background in designing, building and repairing amplifiers. I was extremely pleased with his work and professionalism and highly recommend contacting for your Phoenix Gold capacitor replacements!

The 2nd part to my shootout between the 150HD and MS-275 involves resistive power output tests using 100hz test tones. This may not be the most accurate method for obtaining maximum RMS output power, however it is the method I used for this comparison. If you've not seen my bench setup before, see my previous posting about the components used.

Being a huge old school amp fan, I've always wanted to see the power output of the 150HD. Back in the early 90's, there were a few magazine tests of the Phoenix Gold amps (MS-250 and MS-275), but none of the 150HD. I had an idea of the expected power output of the MS-275 based on these magazine tests, but the infamous Punch 150HD had only sample birth sheets and I had never seen an example of the 4ohmsstereo and mono output. I've always heard these RF amps were "very" underrated, but what is the true RMS output? Read more to find out...

The Punch 150HD was a BEAST on the test bench. Rated at 75x2 4ohms stereo, it put out an effortless 119.2 watts x 2! The MS-275 was much less powerful at 80.9 x 2 into 4ohms stereo. It has been mentioned before the MS-275 has more "reserve" power for transient peaks, such as those in music. I didn't have a way to test true music output power, so you'll have to consider this when comparing the raw resistive output numbers. I appreciate any and all comments of my testing methods and those who disagree are more than welcomed to perform their own tests!

The Punch 150HD out powered the MS-275 in all of my resistive output tests. Here are the results in order of 4ohms stereo, 2ohms stereo, 4ohms mono and 2ohms mono:

RMS Watt Resistive Output:

1) Rockford Fosgate Punch 150HD - 119.2, 191.8, 299.2 and 330.2
2) Phoenix Gold MS-275 - 80.9, 134.1, 217.5 and 224.7    

See the video below or visit YouTube for the 720 and 1080P High-Definition versions.




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