Kind of a 'rms vs peak' debate

[ladysmanfelpz 10+ year member]

So yes i did use the search but im looking for a little more info here from knowledgeable people. So my set up is pioneer 6 1/2s 225w max wired at 2 ohms left and right powered by an alpine t220 and a 10" cvx in ported box wired at 2 ohm powered by alpine mrp450 rated at 400w rms. So my first question is why are some amps 2 ohm stable and some not? Guessing it is just some can handle it and some can't based on how they are made, but with my t220 it is rated at 50w x 2 at 4 ohm and 70w x 2 at 2 ohm. I thought if you cut the ohm load in half, power doubles so it should be 100w x 2 at 2ohm, but is it something in the engineering in the amp that limits it? And also if I am pushing 70w to each channel that means each resistor (speaker) gets then 35w each correct? And so how do you reach peak power of an amp, as the t220 is rated at 250watts peak? I know people say don't look at peak for a build, but its there for a reason. So if I am playing my music at full tilt so its pushing its 70 rms and then a loud section comes in through the signal, if the power is provided it will be able to push a lil more power beyond the rms, so that you don't get distortion and volume drop. Is that a correct understanding of peak power of an amp?

Guess my main question is how can you maximize power output of an amp?

I have less than a foot of 4ga wire running from my capacitor to my amps so they are receiving a ton of current, so hopefully i am allowing them to run as efficiently as possible. Sorry for the long write up and all the questions. Thanks for the help.

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[winkychevelle 10+ year member]

Peak power is only available for milliseconds at best case scenario 14.4v and exactly 2ohm or what ever minimum load is. It's a spec that is useless and asking about it will only get u flamed. If you want the best do that pioneer feed it 4gauge power and set the gain right that's goin to get the most out of the amp regardless if it is 50w or 250w. And 9/10 u are only using 15-30w at regular listening levels.

 

[Kangaroux 5,000+ posts]

Theoretically half the resistance means double the power which is TRUE, but you have 2 big factors that cause the amp to not follow this theory: heat and efficiency. No energy in the universe can be changed without heat as a byproduct. With heat comes inefficiency because a percentage of that energy that's being changed has to become heat. The higher the resistance the less the heat, which is why the efficiency is higher and also why the ratings seem to match up for 4 ohms and 2 ohms, but is off for the 1 ohm rating (4 ohm and 2 ohm efficiencies are much closer to 100% than 1 ohm efficiency is)

Also, max ratings are bogus. They are random numbers companies put on their products to make them look better than they really are.

 

[LBC]

Theoretically half the resistance means half the power which is TRUE, but you have 2 big factors that cause the amp to not follow this theory: heat and efficiency. No energy in the universe can be changed without heat as a byproduct. With heat comes inefficiency because a percentage of that energy that's being changed has to become heat. The higher the resistance the less the heat, which is why the efficiency is higher and also why the ratings seem to match up for 4 ohms and 2 ohms, but is off for the 1 ohm rating (4 ohm and 2 ohm efficiencies are much closer to 100% than 1 ohm efficiency is)
Also, max ratings are bogus. They are random numbers companies put on their products to make them look better than they really are.

Half resistance means double theoretical power. The limiting factor in this case is probably rail voltage.

Max doesn't mean anything at all. It's a marketing gimmick to trick people into buying things that they ordinarily would not buy.

 

[Kangaroux 5,000+ posts]

Half resistance means double theoretical power. The limiting factor in this case is probably rail voltage.Max doesn't mean anything at all. It's a marketing gimmick to trick people into buying things that they ordinarily would not buy.

Woops, meant to type double and not half. Good catch

 

[ladysmanfelpz 10+ year member]

But alpine seems conservative with their max power ratings. I'm asking on a big hit does my amp produce more power (higher than normal rms) if the power is provided?

 

[Kangaroux 5,000+ posts]

But alpine seems conservative with their max power ratings. I'm asking on a big hit does my amp produce more power (higher than normal rms) if the power is provided?

Yeah but it's so quick that you won't notice it, not to mention the difference in power isn't big enough to be audible anyways, especially not for the fraction of a second that it happens

 

[ladysmanfelpz 10+ year member]

Oh okay. So my cvx has an rms of 600 watts but my m450 has an rms of 400 watts. Since I am underpowering it, does that mean I can turn my gain to max and it will not clip? It also will not be as loud as it can be because I am not producing the full sine wave the sub is intended to drive right? I am going to have my amps tuned here soon at a local shop, but just trying to get a little more understanding of it all before I bring it in.

 

[xShoWTeKx 10+ year member]

Oh okay. So my cvx has an rms of 600 watts but my m450 has an rms of 400 watts. Since I am underpowering it, does that mean I can turn my gain to max and it will not clip? It also will not be as loud as it can be because I am not producing the full sine wave the sub is intended to drive right? I am going to have my amps tuned here soon at a local shop, but just trying to get a little more understanding of it all before I bring it in.

do not turn it up it will clip, it doesn't matter what power it's rated at if you crank the gain it's going to clip.

and i don't even know what your talking about a full sign wave as long as your crossovers on your amp are right and the it's in a good box it should do what it's designed to do.

 

[LBC]

Oh okay. So my cvx has an rms of 600 watts but my m450 has an rms of 400 watts. Since I am underpowering it, does that mean I can turn my gain to max and it will not clip? It also will not be as loud as it can be because I am not producing the full sine wave the sub is intended to drive right? I am going to have my amps tuned here soon at a local shop, but just trying to get a little more understanding of it all before I bring it in.

the gain is not a control of percentage of amp power in relation to how far you turn the knob. It is there to match the amplifier's progression of amplification to the head unit's outputs. This means when your head unit is turned to max unclipped volume, your amplifier should also be at max unclipped volume. THEORETICALLY if you have 4v preouts then you set your gain to "4v". With that said, things don't always work out that way, but that is the intention. Do not just crank your gain because you think your sub needs more. It doesn't. Your amp can't do it. Have the shop set it. It will be at it's max. Don't mess with it. If you're unhappy with the output, just save up for a more powerful amplifier. You will end up spending that money to get your sub, amp, or both replaced if you just crank your gain. It's actually more cost effective to save up for more powerful amp, sell the amp you have, and call it a day.

 

[ladysmanfelpz 10+ year member]

Alright cool. Ya im pretty much done messing with my system now that I got rid of my pawn shop crap mtx 5 channel and got good clean power going to my speakers. Gonna have the shop set the gains and leave it and enjoy //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[>>SQL<< 10+ year member]

Can you explain how you have your Pioneer 6.5's wired at 2 ohms? Do you have 4 of them?

"pioneer 6 1/2s 225w max wired at 2 ohm"

 

[hispls 5,000+ posts]

TLDR

"Peak" is likely bvllshit as is RMS which in context is absurd. The only numbers that mean anything are current and voltage, which almost nobody provides because there's less wiggle room to try and impress people with nebulous rubbish and marketing.

Amps will more or less double power as you drop impedance doYour wn half at the expense of efficiency (read: they get hot quicker), sound quality, and stability (they will be more likely to fail).

Your capacitor is most likely all but worthless.

 

[ladysmanfelpz 10+ year member]

[quote=>>SQL

"pioneer 6 1/2s 225w max wired at 2 ohm"

Ya they are more 4 door speakers. Car was wired up for an amp before I bought it. It is just wired up left and right. Left positive and negative to front speaker wired back parallel to rear speaker, and same on the right side. Still plays stereo at a 2 ohm load now. My amp is 2 ohm capable so that is no worries, but idk if it affects the speakers at all.

 

[>>SQL<< 10+ year member]

Ya they are more 4 door speakers. Car was wired up for an amp before I bought it. It is just wired up left and right. Left positive and negative to front speaker wired back parallel to rear speaker, and same on the right side. Still plays stereo at a 2 ohm load now. My amp is 2 ohm capable so that is no worries, but idk if it affects the speakers at all.

you got it right.