clipping questions

[darthvibrator]

i just bought some jbl 608gti to replace some ctx65cs. i like the speakers so far. they are rated at 150wrms and 600wmax. right now im running an unclipped 300w to each side as per a snap-on ocillioscope at vol 72. ive heard from others that they've ran 450wrms to these sets to really make them sing.

at 300w, they get pretty loud but they still sound kind of starved for power, the mids have a 2" vc so id assume they can take some decent power. now at vol 72 i can play them all day. if i up it to say 74-75 (im in the clipping zone now since 72 is maxed out) they get louder but after a bit i can smell them. either the xover or the mid.

i find it odd that i can keep it at 72 and its fine, but a slight clip and they dont like it. so let me ask, is this smell due to clipping (esentially dirty overpowering right?) , or is it simply from overpowering regardless of a clipped signal, and ive maxed them out (could i run 400w to them so long as its unclipped?)

or am i playing with fire?

[mackin]

Playing with fire. Maybe I'm just paranoid because my BL caught fire... lol

[darthvibrator]

Playing with fire. Maybe I'm just paranoid because my BL caught fire... lol

what?!

[jesus]

:wtf:

[mackin]

lol yep. Happened last summer. Came home from something, went inside, and decided I was going to go get something from my car, I see smoke coming from the hole in the middle of the back seat (the thing you can put ski's through or whatever).

So I quick open the trunk, rip the wires out of my box, pull the box out and watch it smoke like a mofo on my front porch.

[darthvibrator]

lol yep. Happened last summer. Came home from something, went inside, and decided I was going to go get something from my car, I see smoke coming from the hole in the middle of the back seat (the thing you can put ski's through or whatever).

So I quick open the trunk, rip the wires out of my box, pull the box out and watch it smoke like a mofo on my front porch.

well if it makes you feel better my buddies civic caught on fire randomly. shits "totaled" lol

[darthvibrator]

but seriously, is 300 clipped watts truly any different than 300 clean watts in terms of a speakers ability to handle power? or is distortion the only difference?

[mackin]

well if it makes you feel better my buddies civic caught on fire randomly. shits "totaled" lol
Damn that would suck.

I reconed my BL. It was in the trunk for about a week, and one day I opened it to find the box up against the back wall of the trunk. It wore down the surround in a couple parts. I said FML and just took it out. Never installed in the Jeep when I got it.
but seriously, is 300 clipped watts truly any different than 300 clean watts in terms of a speakers ability to handle power? or is distortion the only difference?

dontaskmebro. Apparently idk what's going on.

[jesus]

Are you being serious? 100 watts clipped would do damage.

[darthvibrator]

Are you being serious? 100 watts clipped would do damage.

yea im being serious. im just trying to conclude whether my overpowering of the speakers is because im clipping them (which supposedly is overpowering) or is it because im simply going over their limits clean wattage or not

[jesus]

What amp are you running and how do you have it wired?

[darthvibrator]

What amp are you running and how do you have it wired?

Effects of clipping

In power amplifiers, the signal from an amplifier operating in clipping has two characteristics that could damage a connected loudspeaker:

*
Difference between clipped and maximum unclipped waveforms
Because the clipped waveform has more area underneath it than the smaller maximum unclipped waveform, the amplifier produces more output power. (See the waveform to the right for an example.) This extra power can cause damage to loudspeaker components, including the woofer, tweeter, or crossover, via overheating.
* In the frequency domain, clipping produces harmonics at higher frequencies than the unclipped signal. This additional high frequency energy has the potential to damage a loudspeaker's tweeter via overheating.

Other effects of clipping include:

* Music which is clipped experiences amplitude compression, whereby all notes begin to sound equally loud because loud notes are being clipped to the same output level as softer notes.


thats a quote from wikipedia. the bolded text seems to suggest that im just overpowering my speakers and even more clean wattage wouldnt help.

im running http://www.kaboodle.com/reviews/rockford-fosgate-25-to-life-punch-150

birthsheet claims 300w rms at 4 ohms. my unclipped voltage on the scope shows 34v unclipped (using that bullshit dmm gain setting tutorial the amp seems to be right in line with the birthsheet)

[jesus]

Punch 150, 75x2 @ 4 ohms, 90x2 @ 2 ohms, 180x1 @ 4 ohms. Built in crossover, Variable input sensitivity, short circuit protection, MOSFET output circuitry. Patented "Punch" equalization, Bridgeable.

This is what I'm finding on multiple sites. I think you might be clipping the shit out of it if your voltages apply to 300w.

Also you're understanding of clipping is wrong. It's not so much about power as it is the signal flattening off and overheats the sub.

[darthvibrator]

This is what I'm finding on multiple sites. I think you're clipping the shit out of it if you're voltages apply to 300w.

its an anniversary edition. rated super low but puts out lots of power like the old rf. the birthsheet states 300w and ive seen others around there.

using the gain setting tutorial if i want 300w at 4 ohms id need to set my gains to 34.6v. the scope shows a clean voltage upto 34v which seems to suggest the amp does rated power (off the birthsheet). this amp is as big as my sub amp which supposedly does 2k watts.

[jesus]

I honestly don't know anything about your amp but is that rating based on the bridged power at 4-ohms?

[darthvibrator]

I honestly don't know anything about your amp but is that rating based on the bridged power at 4-ohms?

no, bridged it supposedly does around 800 or something. id have to find the birthsheet.


hmmm, i just realized something. maybe i should bridge the amp to 1 channel and just listen to that one channel (set gains to around 400w or so, which would mean a lot of overhead and no clipping) and see where it gets me.

[jesus]

To bridge the amp your load would be 2 ohms in parallel which wouldn't be stable.

[darthvibrator]

To bridge the amp your load would be 2 ohms in parallel which wouldn't be stable.
what?

the amp makes some 800w at 4 ohms bridged. i run a set of 4 ohm components speakers.

this would still be a 4 ohm load on the amp.

am i missing something?

edit: ohhh, i think you thought i meant bridge it and wire the speakers in parralel. what i meant was bridge the amp to get 800 or whatever watts to 1 channel, and put that power on 1 speaker set (leave the other side unhooked), set it to 34v (300w) at a lower voltage (say, 50 on the HU) and then go up in volume from there and see if i get the same signs of overpowering (ie, shit smell) or if i get more output that stays clean

[IamDeMan]

This is what I'm finding on multiple sites. I think you might be clipping the shit out of it if your voltages apply to 300w.

Also you're understanding of clipping is wrong. It's not so much about power as it is the signal flattening off and overheats the sub.
http://www.bcae1.com/images/gifs/vcheat2.gif

[jesus]

Bada ba ba bah........I'm loving it!

[IamDeMan]

OK, that image does not work so well on a white background LOL.

George, I believe when you run it unclipped, you are nearing the power handling of that set. I am actually surprised you run that much reliably and I am skeptical about this 450WRMS claim you say other people have said.

The image above illustrates how the clipping is making the drivers see more total power over time periods. It is not necessarily "more power" overheating the coil but rather the amount of time it is seeing this much power.

[IamDeMan]

The RMS voltage of a pure sine wave is equal to the peak voltage multiplied by 0.707. The RMS voltage of a pure square wave is equal to the peak voltage

Note:
If your speakers are capable of handling significantly more than your amplifier can produce, driving them with a clipped signal will not likely hurt them.
If the speakers can handle 3 or 4 times the power that your amplifier can produce, there's virtually no way to damage your speakers (no matter how clipped the signal is).
If your speakers are rated for the same power handling as your amplifier is capable of producing cleanly, driving them with a clipped signal for extended periods of time may cause speaker damage and/or premature failure.
If your speakers are rated for the same power handling as your amplifier is capable of producing cleanly, driving them with a square wave signal for extended periods of time will likely cause speaker damage.

-BCAE

[ramos]

i just bought some jbl 608gti to replace some ctx65cs. i like the speakers so far. they are rated at 150wrms and 600wmax. right now im running an unclipped 300w to each side as per a snap-on ocillioscope at vol 72. ive heard from others that they've ran 450wrms to these sets to really make them sing.

at 300w, they get pretty loud but they still sound kind of starved for power, the mids have a 2" vc so id assume they can take some decent power. now at vol 72 i can play them all day. if i up it to say 74-75 (im in the clipping zone now since 72 is maxed out) they get louder but after a bit i can smell them. either the xover or the mid.

i find it odd that i can keep it at 72 and its fine, but a slight clip and they dont like it. so let me ask, is this smell due to clipping (esentially dirty overpowering right?) , or is it simply from overpowering regardless of a clipped signal, and ive maxed them out (could i run 400w to them so long as its unclipped?)

or am i playing with fire?

Couple questions.

Are you running them passively?

Are you deaf?

I'm running 300w to each driver in my front stage. I can't get the volume past half way before ears start bleeding. 450w to a set of passives means the drivers are probably seeing in the neighborhood of 200w per speaker depending on the crossover. It shouldn't take that much power given the frequency range they play. I have a pair of those jbl's, and they are monsters with just 150w a driver.

[ramos]

OK, that image does not work so well on a white background LOL.

George, I believe when you run it unclipped, you are nearing the power handling of that set. I am actually surprised you run that much reliably and I am skeptical about this 450WRMS claim you say other people have said.

The image above illustrates how the clipping is making the drivers see more total power over time periods. It is not necessarily "more power" overheating the coil but rather the amount of time it is seeing this much power.


450 with the passives is possible with the gti's, no where close to being needed, but it is possible. the crssover would soak up 50w or so, with the drivers seeing roughly 200w each.

[IamDeMan]

450 with the passives is possible with the gti's, no where close to being needed, but it is possible. the crssover would soak up 50w or so, with the drivers seeing roughly 200w each.
Oh you are saying 450 as in 225 per side?

I assumed he meant 450 per channel and that he is running 300 per channel.

I must have read wrong.

[IamDeMan]

. right now im running an unclipped 300w to each side as per a snap-on ocillioscope at vol 72.


Here is where I got that assumption from.

[ramos]

Oh you are saying 450 as in 225 per side?

I assumed he meant 450 per channel and that he is running 300 per channel.

I must have read wrong.

No I meant per side. 450 into the passives, 50w or so soaked up by the crossover, 200w to the mid, 200w to the tweeter.

[IamDeMan]

No I meant per side. 450 into the passives, 50w or so soaked up by the crossover, 200w to the mid, 200w to the tweeter.

Ah I see. I am not separating each side in my head. Still sounds impressive. Then again, I did look them up and they look pretty beefy. They remind me of the Dynaudio made Cadence set I had. That set acted like it could keep taking the power, but in the end I was not happy with the sound of them.

[pl8er]

are these the most inefficient speakers ever made by man.

[ramos]

Ah I see. I am not separating each side in my head. Still sounds impressive. Then again, I did look them up and they look pretty beefy. They remind me of the Dynaudio made Cadence set I had. That set acted like it could keep taking the power, but in the end I was not happy with the sound of them.

They are quite beefy, but that amount of power is way overkill for extended listening.

[ramos]

are these the most inefficient speakers ever made by man.

Pretty much lol JBl and "efficient" don't venture into the car audio realm together very often.

[pl8er]

I thought it was pretty crazy to have 130watts on comps before. 450watts?? WOWZa!

[ramos]

Techically I have 600w per driver in my car for a total of 4800w. But they never see 600w. Headroom is a wonderfull thing if you can control it and your fingers on the gains lol

[darthvibrator]

OK, that image does not work so well on a white background LOL.

George, I believe when you run it unclipped, you are nearing the power handling of that set. I am actually surprised you run that much reliably and I am skeptical about this 450WRMS claim you say other people have said.

The image above illustrates how the clipping is making the drivers see more total power over time periods. It is not necessarily "more power" overheating the coil but rather the amount of time it is seeing this much power.

wow, i just NOW understand the power over time thing (didnt see that white square wave at first lolz). for some reason i couldnt grasp that concept. thanks

Couple questions.

Are you running them passively?

Yes, they are ran passive with the jbl xover, tweeter at +2

Are you deaf?

not deaf, although im sure ive fucked up my hearing some what. however, both me and my friend were like "hmm, these dont get that loud". for some reason ive never been happy with output from my components. ive ran a few other component sets that were supposed to get "extremely loud" (according to online users) off 300w in my explorer (the jbl's are in my frontier) and ive been dissapointed everytime. i did run some morel tempo 6's, which were the loudest set ive ever heard once you kind of abused the set, but those were incredibly loud, but those were just 1 set of speakers.

I'm running 300w to each driver in my front stage. I can't get the volume past half way before ears start bleeding. 450w to a set of passives means the drivers are probably seeing in the neighborhood of 200w per speaker depending on the crossover. It shouldn't take that much power given the frequency range they play. I have a pair of those jbl's, and they are monsters with just 150w a driver.

hmm, maybe i just suck dick at installing? id love to hear someone elses install, to see if its me or the speakers, or at least to see what other people consider loud. it'd be nice to get some perspective.

thanks brosephs.

[ramos]

"Loud" as in loud to the ear is a very relative term. Frequency also plays a big roll in the perception of loudness. When hearing damage (Tinnitus) starts setting in, it's the higher frequency's you start losing first.

[_AnGeL_]

go PA if you want loud.

[pl8er]

pretty sure he wants loud and clean

[_AnGeL_]

you can have that with a PA set-up :fyi:

[ramos]

If you properly use the pa drivers yes you can in fact have loud and clean sound. If you misuse them and install them like 99.99999999999999999999999999999999999999999999% of the idiots using them, you get loud......

[_AnGeL_]

If you properly use the pa drivers yes you can in fact have loud and clean sound. If you misuse them and install them like 99.99999999999999999999999999999999999999999999% of the idiots using them, you get loud......

come install mine? :D

[pl8er]

a mexican with a PA system, that is a new one.

http://www.2dayblog.com/images/2008/september/dj_mobile_1.jpg

[ramos]

come install mine? :D

You want to use multiple drivers in the doors. look at the specs of most pa speakers, run them through some enclosure software and tell me what you come back with for enclosure size.......... Better have some big damn doors.

[_AnGeL_]

http://www.dbdragpr.com/DB/Gallery/main.php?g2_itemId=41948&g2_page=1

[_AnGeL_]

You want to use multiple drivers in the doors. look at the specs of most pa speakers, run them through some enclosure software and tell me what you come back with for enclosure size.......... Better have some big damn doors.

so should I go with just the 8" and the tweeter?

[ramos]

http://www.dbdragpr.com/DB/Gallery/main.php?g2_itemId=41948&g2_page=1

Hell I don't need photo's of the rich port. It's all over the place here in hillbillyville :(

[ramos]

so should I go with just the 8" and the tweeter?

You could possibly squeeze two in. The point I was getting at is reaching the point of diminishing return. There is no perfect anything, especially in the realm of audio. There is always a trade off. more drivers playing the same frequency band will be louder to a certain point given the drivers are in an optimal enviroment. How ever, putting 4-5 drivers in a common airspace that is too small for one of them is just shooting yourself in the foot. Yeah the power handling on the drivers in that tiny cramped space will go up slightly, at the expense of efficiency. Which defeats the purpose of using the efficient pa drivers in the first place. See what I'm getting at here ?

[_AnGeL_]

You could possibly squeeze two in. The point I was getting at is reaching the point of diminishing return. There is no perfect anything, especially in the realm of audio. There is always a trade off. more drivers playing the same frequency band will be louder to a certain point given the drivers are in an optimal enviroment. How ever, putting 4-5 drivers in a common airspace that is too small for one of them is just shooting yourself in the foot. Yeah the power handling on the drivers in that tiny cramped space will go up slightly, at the expense of efficiency. Which defeats the purpose of using the efficient pa drivers in the first place. See what I'm getting at here ?

I'm sayin' :hi5: I used to try and tell my friends that when i lived in pr, but they wouldn't listen. then they wondered why my door pods (with 2 6's) were louder than their doors with 2340923841209381230921380 speakers lol.

[ramos]

Some people just want to throw money at something without thinking about it. I have done a few installs that the owner just wouldn't listen lol

[JimJ]

you can have that with a PA set-up :fyi:

Sure, but good luck getting anything resembling a stereo image unless you're willing to do some work ;)

But if all you want is that tssss tsssss to go with that booooom boooooom, go for it...

[JimJ]

so should I go with just the 8" and the tweeter?

Would have to be one hell of a beefy tweet to extend that low, or prepare for lobing...

[ramos]

Or a better 8" to play higher *cough* B&C *cough*

[darthvibrator]

update: damn son, these speakers sound so good