difference between amp and sub clipping?

[SuperSaeYoung]

RMS means "root mean squared" it's a handy way to find an average variance from 0 from a group of numbers (positive and negative mixed or the mean can be derived without the square and root). RMS does NOT mean power.
POWER = square root of (current * impedance), or current * voltage, or whatever other variation of the equation

IMO unless you're playing one specific tone at a specific record level any form of "precision" gain setting is pointless. To match all potential unknown program material at unknown record levels cannot be done.

My method is head unit volume around 2/3 to 3/4 depending on the head unit, gain it up til it doesn't get any louder when you turn it up more, then turn it back a little bit. Except in cases of grossly over-powering speakers I've never blown stuff up with this method. The point is to have your max undistorted output somewhere before the top of the dial on your head unit so that you're not pushing that into a clipped signal when you need a little more gain to overcome low record levels. Anything you throw in for source material beyond your test track will require a little discretion and knowing when to back off.

And I still have yet to fathom why everyone feels the need to use the term RMS in regards to an AC signal, considering 99% don't understand what it means, where it comes from and why it's not relevant.

99% of the people see it's been used on the speaker boxes, website, manual, speaker itself, and people on forums.

I thought power was

P=I^2*Z not P=SQRT(I*Z)

 

[quackhead 10+ year member]

That is horrible advice. You shouldn't not be eyeballing your gain because you may be clipping and won't even know it. You can still be clipping and not hear it. An O-scope would be the best way to go, or the DD-1, but if neither then should at least use a DMM.
Op do NOT just eyeball your gain. You will more than likely clip your shit.

dude...most amps' gain adjustments do not show incremental settings between the lowest and highest, I was stating that op should first KNOW his HU's signal output voltage..whether it is by owner manual, DMM or whatever..Yes, DMMing the outputs are a good way, but is really just bs unless you are competing and trying to focus in on a certain frequency. I deff. see your point in what I said, but to know the voltage and initially set your gain accordingly, would be a fair way to START setting the gain. I guess I should have wrote another dang paragraph explaining proper gain setting technique...geez! I was attempting to give a brief description of what and why regarding clipping. Especially what happens when u crank up on that little gimmicky 40 hz bass boost knob that ALOT of companies toss in with their amps these days.

 

[quackhead 10+ year member]

that was helpful as **** thank you very much. so if my headunit puts out 4 volts i wanna get the gain at about 4 volts on the amp? it was a little higher than that and i was clipping i'm pretty sure so i'm hoping this helps

Yup... there are alot of other variables involved (and opinions) like excessive bass boost, loudness controls, eq settings, etc. that can cause your amp to clip prematurely... i did not give you any advice that would harm your stuff..and I am assuming you were clipping your subs?

 

[IonRL205 10+ year member]

dude...most amps' gain adjustments do not show incremental settings between the lowest and highest, I was stating that op should first KNOW his HU's signal output voltage..whether it is by owner manual, DMM or whatever..Yes, DMMing the outputs are a good way, but is really just bs unless you are competing and trying to focus in on a certain frequency. I deff. see your point in what I said, but to know the voltage and initially set your gain accordingly, would be a fair way to START setting the gain. I guess I should have wrote another dang paragraph explaining proper gain setting technique...geez! I was attempting to give a brief description of what and why regarding clipping. Especially what happens when u crank up on that little gimmicky 40 hz bass boost knob that ALOT of companies toss in with their amps these days.

Yeah most amps dont' show incremental settings below lowest and highets, so why the fuck would you tell the OP to just eyeball his gain if he has no idea how much the increments are? You just completely failed from your first line.

The DMM method is the best way for people to set their gains if they don't have access to an o-scope or a DD-1, whether you're competing or just daily. You don't need to know your HU voltage if you use the Dmm method. Just use the formula and it will give you a certain voltage your amp will put out for that RMS rating and turn up your gain until your DMM reads it, and just back off a hair. Please tell me how just eyeing your gain and hoping you don't go too high is a better method than using a DMM.

Just eyeing the gain is NOT a good way to start. You can't just look at it and assume you are in the right spot, because more than likely you aren't. You are giving the OP terrible advice and leading him in the direction to clip his ****. Just don't post if you are gonna say dumb shit.

Yup... there are alot of other variables involved (and opinions) like excessive bass boost, loudness controls, eq settings, etc. that can cause your amp to clip prematurely... i did not give you any advice that would harm your stuff..and I am assuming you were clipping your subs?

Yes you did give the op horrible advice. You told him to just eye his gain and hope to get lucky. That is a VERY easy way to clip things since you have no idea if you are too high or to low.

Like I said OP, DO NOT EYEBALL YOUR GAIN. Just buy a $10 dmm and use that method.

 

[quackhead 10+ year member]

Yeah, I don't get how he has good knowledge on the subject, but gives the worst way for the op to set his gain and the easiest way to clip his shit lol

Please, by all means explain why setting your amp's gain setting to the HU max input voltage can be the easiest way to clip?...OP turned down their gain to closer match his line inputs...was it not mission accomplished?...LOL...and your post made them turn down the volume all together, yet no one here has bothered to explain how to actually set a gain, because the ONLY way to not clip a sub is to set it at one frequency and only play that one frquency..OK, OP...your gain is set close to 4v, you say your hu puts out 4v, put in your fave song and slowly turn up the HU volume until you can hear or feel you are getting distortion, or even bottoming out, if that's the case with your sub...if you sense distortion at less than 3/4 volume, turn down the amp gain and try to work up to the 3/4 volume level on your HU. If you can reach 3/4 volume on the HU and know in your heart that it it sounds too good and there's more, turn up the amp gain until you know it starts to clip/distort.....

My personal problem with advising the above method is that your ears become insensitive to loud volumes very quickly and it can be very easy to get into some serious distortion in the lower frequencies without a meter or a blinking light to confirm this....I do not own a O-scope and bet OP doesn't either.

 

[MisterDeadeye 10+ year member]

[quote name='IonRL205']Just buy a $10 dmm and use that method.[/QUOTE]

Parts-Express has one for $3.xx today as their deal of the day. :fyi:

@hispls You shouldn't be so mean. I'm sure you know he was referring to power.

 

[IonRL205 10+ year member]

Please, by all means explain why setting your amp's gain setting to the HU max input voltage can be the easiest way to clip?...OP turned down their gain to closer match his line inputs...was it not mission accomplished?...LOL...and your post made them turn down the volume all together, yet no one here has bothered to explain how to actually set a gain, because the ONLY way to not clip a sub is to set it at one frequency and only play that one frquency..OK, OP...your gain is set close to 4v, you say your hu puts out 4v, put in your fave song and slowly turn up the HU volume until you can hear or feel you are getting distortion, or even bottoming out, if that's the case with your sub...if you sense distortion at less than 3/4 volume, turn down the amp gain and try to work up to the 3/4 volume level on your HU. If you can reach 3/4 volume on the HU and know in your heart that it it sounds too good and there's more, turn up the amp gain until you know it starts to clip/distort.....
My personal problem with advising the above method is that your ears become insensitive to loud volumes very quickly and it can be very easy to get into some serious distortion in the lower frequencies without a meter or a blinking light to confirm this....I do not own a O-scope and bet OP doesn't either.

You fail harder and harder every time you post. You even said the amp doesn't give increments, so you're basically setting the gain to just a random spot and hoping you are in the correct place. Also music is not constant and not all songs are recorded at the same db level, so just cause you set your gain with one song does not mean you're not going to be clipping playing another. Also what sounds good to one person may sound like garbage to another, just cause it sounds good to you doesn't mean you're not clipping. You can be clipping and not hear it.

You just keep saying dumb things over and over. You do know that when the DMM reads the voltage you are supposed to set your amp at, your amp is matching the pre-out voltage of your head unit right? Its exactly the same thing as just eyeing it, just way more accurate. How is this so hard to understand?

Just stop posting stupid things, your method is a horrible way to set the gain and you just look stupider and stupider every time you post.

 

[IonRL205 10+ year member]

dbl ftl

 

[Buck 5,000+ posts]

Next step is finding out how many of your favorite songs are clipped //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif

 

[quackhead 10+ year member]

Yeah most amps dont' show incremental settings below lowest and highets, so why the fuck would you tell the OP to just eyeball his gain if he has no idea how much the increments are? You just completely failed from your first line.
The DMM method is the best way for people to set their gains if they don't have access to an o-scope or a DD-1, whether you're competing or just daily. You don't need to know your HU voltage if you use the Dmm method. Just use the formula and it will give you a certain voltage your amp will put out for that RMS rating and turn up your gain until your DMM reads it, and just back off a hair. Please tell me how just eyeing your gain and hoping you don't go too high is a better method than using a DMM.

Just eyeing the gain is NOT a good way to start. You can't just look at it and assume you are in the right spot, because more than likely you aren't. You are giving the OP terrible advice and leading him in the direction to clip his ****. Just don't post if you are gonna say dumb shit.

Yes you did give the op horrible advice. You told him to just eye his gain and hope to get lucky. That is a VERY easy way to clip things since you have no idea if you are too high or to low.

Like I said OP, DO NOT EYEBALL YOUR GAIN. Just buy a $10 dmm and use that method.

LOL...STFU and go back to school before YOU make someone ruin their equipment.

 

[quackhead 10+ year member]

ummkaayy...lets take this back to the original question at hand...

difference between amp and sub clipping?

is there a difference between these two? like if you're clipping the amp does that automatically mean your clipping the sub too?

the sub does not clip....the amplifier clips the signal when the input section is overdriven, the subs just die from trying to reproduce that amplified clipped signal.

 

---------- Post added at 12:51 PM ---------- Previous post was at 12:50 PM ----------

 

ummkaayy...lets take this back to the original question at hand...

difference between amp and sub clipping?

is there a difference between these two? like if you're clipping the amp does that automatically mean your clipping the sub too?

the sub does not clip....the amplifier clips the signal when the input section is overdriven, the subs just die from trying to reproduce that amplified clipped signal.

 

[keep_hope_alive Premium Member]

That is horrible advice. You shouldn't not be eyeballing your gain because you may be clipping and won't even know it. You can still be clipping and not hear it. An O-scope would be the best way to go, or the DD-1, but if neither then should at least use a DMM.
Op do NOT just eyeball your gain. You will more than likely clip your shit.

there was nothing to eye-balling the gain. his approach, which is conservative, is setting the amp gain to the HU output voltage. if you have a 5V head unit, set the amp gain at 5V. typically, this method means you'll never achieve rated output on the amp since you'd have to try hard to actually achieve rated output on a HU, but you'll never clip at the amp either. any clipping will be back at the HU. that is the only risk here, some HU's clip, some don't.

if you have a HU powering speakers, and a sub amp, then this method isn't useful since you'll never want to crank the HU volume. that is when using tools are required to match the HU output to the amp input sensitivity. sadly, a DMM is useless here since you don't actually know the HU output voltage at mid-volume. this is where a scope is required. so you can visually see the waveform and adjust gain accordingly.

using a Scope is required when you want to make rated power output while NOT achieving rated HU pre-out voltage. as such, the gain setting will be higher since you are working with a lower input signal. this is more risky since you have to constantly be aware of the HU volume and signal strength.

ideally, you'd have everything externally amplified, all amp gains set at the HU output voltage, and then lower gains from there to achieve desired level matching. easy and foolproof and you can make use of the entire HU volume range (assuming the HU won't clip at full volume, mine don't).

the only thing a DMM is really good for is matching amp gain on both channels of a stereo amp (since the pot dials aren't equal). setting gain with it based on Ohm's law calculations carries a lot of assumptions.

 

[hispls 5,000+ posts]

99% of the people see it's been used on the speaker boxes, website, manual, speaker itself, and people on forums.
I thought power was

P=I^2*Z not P=SQRT(I*Z)

Use of RMS explained:

rms and peak

Pretty much unless you're reading an osciloscope or an engineer, every voltage, current, and power figure you'll deal with as far as AC goes will be the RMS value. When people talk about 110V or 220V lines in the home they never say RMS (though that is an RMS figure). I haven't seen a home appliance that needs to put RMS after the power consumption.

I probably did fvck up that formula, it was about 3:30am when I threw that out. I'll stand behind everything else there though.

 

[IonRL205 10+ year member]

there was nothing to eye-balling the gain. his approach, which is conservative, is setting the amp gain to the HU output voltage. if you have a 5V head unit, set the amp gain at 5V. typically, this method means you'll never achieve rated output on the amp since you'd have to try hard to actually achieve rated output on a HU, but you'll never clip at the amp either. any clipping will be back at the HU. that is the only risk here, some HU's clip, some don't.
if you have a HU powering speakers, and a sub amp, then this method isn't useful since you'll never want to crank the HU volume. that is when using tools are required to match the HU output to the amp input sensitivity. sadly, a DMM is useless here since you don't actually know the HU output voltage at mid-volume. this is where a scope is required. so you can visually see the waveform and adjust gain accordingly.

using a Scope is required when you want to make rated power output while NOT achieving rated HU pre-out voltage. as such, the gain setting will be higher since you are working with a lower input signal. this is more risky since you have to constantly be aware of the HU volume and signal strength.

ideally, you'd have everything externally amplified, all amp gains set at the HU output voltage, and then lower gains from there to achieve desired level matching. easy and foolproof and you can make use of the entire HU volume range (assuming the HU won't clip at full volume, mine don't).

the only thing a DMM is really good for is matching amp gain on both channels of a stereo amp (since the pot dials aren't equal). setting gain with it based on Ohm's law calculations carries a lot of assumptions.

The problem with this is, that not all amps label the gain, like my amp. All it says is 9v and 0.2v and nothing in between. There is no way to tell when you are on 5v or not, you could be clipping or you could go higher. I just don't see the point when a DMM is much more effective.

 

[hispls 5,000+ posts]

[quote name='MisterDeadeye']Parts-Express has one for $3.xx today as their deal of the day. :fyi:

@hispls You shouldn't be so mean. I'm sure you know he was referring to power.[/QUOTE]

Not really. I genuinely wasn't following where that one was leading. Could have been voltage or current since either, in regards to an AC signal, would be the standard.

Someone should really make a sticky explaining RMS because it's one of those things people like to tack onto things that really just spreads misinformation and ignorance.