Originally Posted by yllennodmij
WHO makes these mosfet amps. Is it all brand X amps in brand Y head units? or is it actually sony amp in sony head unit?
WHAT are the differences between brands? Are there notable digital samplers going on behind the scenes that nobody knows about?
ok... my first post in the car audio section... even though i have been involved in the industry for almost 30 years.
( not sales, but engineering )
the 4 channel audio amplifier chips in all head units are mostly made by Signetics Thompson ( ST ) or Hitachi. the ST chip is slightly cleaner, but it is not a significant difference. most of the brands use both chips, so you cant really say brand X is cleaner than brand Y. they all have a THD somewhere near a whole 5%.
i would call the companies that say 14 watts RMS a little bit more honest than the companies that say 20 watts RMS... yes, you can overdrive that 14 watt unit to 20 watts... but it sounds like dirt. the 20 watt unit sounds like dirt unless you turn it down to 14 watts. after all, they often use the same chip.
back in the early 2000's Alpine had advertised 27 watts RMS... they used a Signetics Thompson TDA7860 chip... funny that Pioneer used the same chip ( with the Pioneer logo silkscreened on it ) and advertised it as 17 watts RMS. neither could go much above 14 watts and not sound like dirt.
now here is the thing that makes different units sound slightly different. the preamp section. if you go to some of the car audio forums, you will find people who are brand loyal. some are Alpine fans, some Pioneer, some Kenwood, etc. the thing is, is that companies manipulate the sound. in the old days, Alpine used to heavy boost spike low frequencies. in other words, people used to hear a definite stronger bass out of an Alpine than out of others. this holds true, regardless of using the onboard amp, or external amps.
for the guy just replacing the head unit, and keeping the factory speakers, this is a major plus. all of a sudden, there is low frequencies that were not there before.
Kenwood has always been a flatter sound than the rest. Pioneer almost as flat. i actually prefer that, as when running amps, i do not want the sound to be manipulated at all. ( i run McIntosh and Denon head units, about as flat as you can get ) Sony, before the 2000 Xplod line started, had some really nice units. the 1997-1999 Sony CDX-C90 is still one of the most sought after units for flat and clean sound quality.
but, with modern head units, sound manipulation is much less than the old days. thats because they now have multiple band EQ's and bass boost circuits for the user to manipulate it to their preference. Alpine is still ever so slightly bass heavy though. so in that sense, you are correct to say that there is not much difference in the brands.
but... people are a little confused on what sound quality really is. i would say a large percentage confuse tone with sound quality. i have a guy that swears by his old 1996 Alpine CDA-7840 that i keep fixing for him. he claims that the bass spike makes his system sound better. i keep telling him that if he upgrades the rest of the system, he wont want that bass spike. never mind that the 7840 is not exactly a clean or accurate unit, it just makes his less than optimal equipment's tone better. and that is what he considers sound quality.
anyway, if you are in sales, it is best not to argue with the customer. some people have a perception of what is good or not, and it is a near impossible thing to convince them otherwise. just let them listen to whatever and choose for themselves. marketing makes sure that they dont understand that that JL Audio 1000/1 actually has more power than that "3000 Watt" Power Acoustik does. and you will almost never convince them that a $4500 McIntosh MCC602TM 600 watt amp has more power than the JL does. most people would buy the Power Acoustik, because they can get "3000 Watts" for $139.
same goes for head units. just show them the sound settings and let them play with it. they will decide what sounds better, even if they set each unit the exact same.
and also remember, everyones ears are different. what is good to you, may not be to someone else. when setting up a system for my friend, he complained that he could not hear the high frequencies... no amount of EQ could fix it. it then dawned on me that he has been a professional welder for almost 30 years, and his high frequency hearing is almost non-existent. i replaced his door speakers with some cheap Infinity Kappas, which have the harshest metal dome screaming tweeters i know of... he is a totally happy camper now. his system also gives me a splitting headache.