What makes a amplifier sound clean?

What makes some amps sound cleaner than others? I have a Sony 4-channel car amp that is suppose to be 600 watts i put this in to power speakers in place of my Rockford Punch 160.4 thats 20 watts a channel i'm not trying to say this vs that but trying to figure out why the Rockford sounded more warmer and cleaner? I tuned that amp as best as i could and on my Kenwood EQ to get the sound of the Rockford. had to turn it up for it to sound good. The difference is day and night between the two amps. I like loud clean sounds if you were wondering but not abusive. Is it because the components used in the amplifers? And yes i checked all of my wires and rca cables and its not my install i don't think the amp is defective it just doesnt have that clear and warm sound to it idk why Rockford really did it when i had it in.
 

Perry Babin

Member
Paid Member
2003-11-20 11:01 am
Louisiana
www.bcae1.com
The actual power amplifier sections of most all solid state amplifiers sound the same. The high level of negative feedback ensures that the only difference between the input to the power amplifier circuit and the output at the speaker terminals is the level. This only applies if both amplifiers are in proper working order. For amplifiers that sound better, it's possible that the crossovers and boost circuits are better designed.
 

jol50

Member
2007-11-08 2:14 am
The old RF amps (or some of them) are said to have sort of a loudness circuit in them that is on all the time, however you should be able to duplicate this with another amp and an EQ....unless your system response is way off and you run out of EQ or the EQ is of poor quality, etc. You will find this in old amps much more than new amps, and back then (late 80s) it was great since few people even had an EQ. Some RF even had bass and treble on them. This can also minimize typical response issues in cars such as reflections that happen at typical frequency ranges, etc. So you have to be very careful to differentiate between response issues (EQ) and actual quality issues (THD, etc). Another issue is how the amp clips, certainly many old amps will clip far nicer than new amps in particular cheaper new amps. But that is only an issue at max power for a given amp, and new amps have plenty of power so you can avoid that issue if you get a large enough one. That said I have no problem running older amps on mids and highs where power is not much of an issue, or not for me anyway. But often it depends on the install for what I end up liking better.
 
The old RF amps (or some of them) are said to have sort of a loudness circuit in them that is on all the time, however you should be able to duplicate this with another amp and an EQ....unless your system response is way off and you run out of EQ or the EQ is of poor quality, etc. You will find this in old amps much more than new amps, and back then (late 80s) it was great since few people even had an EQ. Some RF even had bass and treble on them. This can also minimize typical response issues in cars such as reflections that happen at typical frequency ranges, etc. So you have to be very careful to differentiate between response issues (EQ) and actual quality issues (THD, etc). Another issue is how the amp clips, certainly many old amps will clip far nicer than new amps in particular cheaper new amps. But that is only an issue at max power for a given amp, and new amps have plenty of power so you can avoid that issue if you get a large enough one. That said I have no problem running older amps on mids and highs where power is not much of an issue, or not for me anyway. But often it depends on the install for what I end up liking better.


Yeah I've decided to keep my RF channel. It sounds just great makes my highs scream! I've always used old RF for my bass those also got the power. I try other brand equipment newer stuff and it just doesn't got the same awesomeness sound as the fosgates do even with out the EQ they still clean & clear. Right now I'm running a Punch 40x2 for bass and a RF Punch HE best sound I've heard. I also have other RF amplifiers to use but these suit me best. Also can i paint a heat sink? The 160.4 is in really bad condition not the amp its self but the heat sink is all scrathed.
 

jol50

Member
2007-11-08 2:14 am
You can paint sinks, but paint build up can increase temperatures inside so it is nicer to replace what they did. Some strip them some not, some send them in for anodizing. If its black paint and kind of flat, what can work nice is the spray for bumper rub strips on cars. Most stores here have spray cans of it. Air dry paint is not the best but what most have access to.
 
In some of the early Rockford amps, the bass boost never went completely off. That could account for the difference in sound. Later, they modified the bass boost circuit so it would go completely flat.



Yeah this is for the mid 90's RF amps right? Like a 40x2 and 160.4. I also noticed that the 1997 Punch 40.2 was the same as the 1996 Punch 40x2. The 97 series didn't have the PSD connection but had the area where it was suppose to be. Very good little amps pushed a variety of speakers I had.
 
How bad have you seen badly blown RF amps? I was browsing ebay for some amplifiers. I see some that are badly fried the power supply is badly burned up. Why do they do that? Seems like when they fail they burn up parts of the board too. Why do they burn the heck up like that? Mostly the DSM, ".2" and "A" series I've seen that were badly burned.
 
What model is the Sony?

The most obvious thing that will make two amps (or radios or whatever for that matter) sound different is different gain. That means if you were doing a direct comparison, but one was playing a little louder. Due to your hearing mechanism, even 100% identical-down-to-the-last-atom components would sound different if one was a bit louder.

But I think you're talking about a sound impression from just driving around.

Are your crossover settings the same? Presuming you didn't change the speakers, if you are using crossovers in the amps you will almost never be able to set them identically due to different circuitry.

Did the Sony not have bass boost, and the Rockford does and it is on? That's a built-in boomy EQ, it will make a huge difference. And as noted, some amps never turn off the bass boost completely. Look at
http://caraudiomag.com/articles/kicker-ix5004-4-channel-amplifier-review
under the heading "What’s The Frequency, KICKER" and you'll see a little bump in the frequency response. Very few amps have an OFF switch to completely remove the boost circuit out of the signal path, and this bump can be the result.

Amplifiers can have measurably significant differences in their noise floor and the shape vs. frequency of that noise; separation/crosstalk between channels; flatness of frequency and phase response; and output impedance/damping factor. The level and types of distortions varies considerably-and the distortion undoubtedly differs dynamically in ways that are not generally measured.

How much can you hear all that? Some say all amps sound the same below the clipping point*; others say they hear noticeable differences in direct comparisons. Since everyone has different hearing, both may actually be right. My experience has been one of hearing subtle differences under swap-it-and-drive conditions like your situation.

*Nobody really debates that amplifiers clip differently and sound different when doing so. If you're overdriving your 20W Rockford, it may be clipping and making a "harder" sound than your Sony was, and maybe you like that.