# 1997-2002 AB class vs. today Masconi Pro or Others



## Mtrhead (May 22, 2020)

I’ve been noticing a slight trend of the high end builds using AB class amps for everything but subs and even the highest some for subs. Find that interesting

The question I have is: What is the real audible difference between a new AB amp like a Masconi Pro or Zapco vs a Precision Power PC series or other good AB of late 90’s? 

Reading spec sheets comparing a PC4100 to a 5/30 not much different than output of the model. Granted the 5/30 has more power for the model but specs are similar or if not slightly inferior to the PC4100. 

Bias? only slightly because I have PC amps in my vintage car, left over from late 90’s, and they work great. However I’m starting to plan a new truck build and I see guys that we’re running Helix or JL have moved to AB amps (why?) and the absolute highest end builds I’ve read have had AB sub amps.

fire away!


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## chuyler1 (Apr 10, 2006)

The question for the ages it seems. 

There has been a lot of improvements in crossover and signal processing technology that is now built-in to many new high end amps. But let's assume in both scenarios you plan on using a DSP and the amps will be run with all those components disabled. The Mosconi has a way to turn it all off, I'm not sure if the PPI does, simply turning dials to lowest setting is not the same. That is partly why some of the older amps are more desirable (1990-96 era) because they have no interruptions in the audio signal.

Next we need to talk about amplifier condition and its effect on the noise floor. A high end amp like the PC4100 likely has circuitry to silence itself if it detects no signal, but how does it handle a quiet signal such as a piano concerto? Worn out gain potentiometers, failing capacitors, loose RCA input terminals, weak solder joints of circuit board components can all play into this. It may have originally had a s/n ratio of 100-102db but does it still have it?

Then there is "a watt is a watt". PPI amps are known to put out exact specs (when new). Many new high end amps want to make sure they make rated power and are often underrated. For it to be a true comparison, you'd want to first ensure you are comparing 100w/ch RMS and the amps have similar dynamic output as well. If the Mosconi is going to send 185w RMS (possibly more if it's underrated) to your midbass and the PPI can only send 100w RMS, you're going to notice that for sure.

There is always the risk of failure and replacement to consider. If you do a custom install with a 25 year old amp, all wires nicely tucked with no slack, can you easily find a replacement that will drop right in if it fails? Otherwise, do you have the skills and free time to repair it? Keep in mind you could be without a sound system while a replacement is sourced or repair is completed.

So to summarize the above into a list of reasons you don't see audio competitors using old gear to win sound-offs...

They don't have the latest DSP features and/or the features they do have sometimes get in the way
They are unreliable and not as easy to replace quickly should something fail
They often don't put out equal power to modern amps despite what the spec sheet says
The installer isn't sponsored and promoted to run them
But your question is what is the audible difference that is not related to worn components or output wattage or distortion due to overdriving the amp?

I can't tell you what the difference is, or which you would prefer, but I can safely say they will sound different in some way. I feel like whatever the difference is, when dealing with quality equipment past or present, a DSP can likely correct it, and if not, road noise is going to hide it anyway.

My vote, keep on using those old high end amps for mids and highs until they fail but definitely consider modern class D for bass.


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## Mtrhead (May 22, 2020)

appreciate the answer! Thank you.


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## ItsonlyaHONDA (Sep 9, 2021)

Class AB Amps: "High End" vs...


I've been wondering about this for a while. I'm not talking about class D as it's been improved greatly over time, but what about class AB? Assuming everything else remains the same (tuning skill, speakers...), will high end class AB amps make a really noticeable difference compared to the "non...




www.diymobileaudio.com


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## Speedhunter (Feb 21, 2020)

This is beaten to death.....

Status, beliefs, looks, domestic support, ignorance and more are the reasons why would be one chosen over another.

I have no problem with people who chose their amps based on mentioned above altought there is a different church full of people pushing technical part of the story which basicaly tolds you its all the same. Some of ignorants categorise it by the price tag; ..." _cheap AB is ****y compared to class D, expensive AB is bla bla..."_

Chose yours.


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