Clipping, Thermal Cooling, and Woofer Efficency.......?

[BassAddictJ 5,000+ posts]

ok......4:45 am and im an insomniac but here it goes......

xxx 15, 4 cubs tunes to 28Hz. hatchback 2002 vw golf, 2 opt red tops, dual 4 gauge power and grounds, big 3 soon, question about switching sub amps

right now its the 1501d and @ 1.5ohms dcr and intended 2 ohms after some imp rise and heat.... (each voice coil is 2.9ohms dcr, both run in paralle to get about 1.5dcr, which the sub is rated as dual 4 ohm voice coils.)

im getting a solid 1300 watts out of that amp with the voltage ive read, however i cant measure current with my tools, so i did voltage squared divided by the ohms to get a rough estimation for the watts. so about 1300-1400watts out of it when running hard.

now the sub heats up after about 20 min of hard playing, and i think its from clipping. because people run xxx15's with alot more than 1300w and have no problems, my cone is getting way hot after 20 min of hard playing. is it possible most of this heat is from mechanical wear from clipping????

and if clipping is a factor of the heat, theoretically would the sub run more efficently with an unclipped signal? even if there's more power being given with the unclipped signal (1600-1800w against 1300w)?? or will alot of heat occur due to the factof which theres more power and subs are only so efficent?

all same car, same electrical system, etc.... amps are currently mtx 1501d, and the next amp that will give more power will be an oldschool planet audio big bang.

thoughts? -5:00am

Click to read more...

 

[RandyJ 10+ year member]

Clipping will cause more heat, simply because the period of time on the signal when the driver is supposed to be heading back towards the trough or peak, it is not, and during that time, there is no motion to create wind resistance which in essence cools the driver. So yes, if you are sending the driver a clipped signal, it has the ability to get warmer than it should be. And you can find current without directly measuring it.

P=EI

I=P/E

 

[squeak9798 5,000+ posts]

http://forum.soundillusions.net/showthread.php?t=47441&highlight=clipping

Pretty interesting. Notice that when the drivers received the same power level, but from two different types of signals (one clipped, one non-clipped), that they still failed about evenly. They couldn't prove that a clipped signal of the same power level as a pure sine wave caused the driver to fail any sooner.

The main problem with clipping isn't so much the clipped signal itself, but rather the increased power output by the amplifier while clipping. If you have a 1300w amp and clip it hard, you'll have ~2600w worth of power being received by the subwoofer.

 

[BassAddictJ 5,000+ posts]

wow cool article....

as for the equations, those are what i used to get my watt readings..

soooo all in all the sub is probly still going to heat up wether its clipped or unclipped.....

how about the efficency of the xxx15, iheard its not that efficent compared to other woofers of its class.

also does anyone reading this have an experience running more than 1600w to a xxx15 ported...?

also...occassionally i get the smell from the woofer and im not sure if its excess gluemelting or voice coil fryage....kinda scary.......

 

[hoss 5,000+ posts]

Clipping will cause more heat, simply because the period of time on the signal when the driver is supposed to be heading back towards the trough or peak, it is not, and during that time, there is no motion to create wind resistance which in essence cools the driver. So yes, if you are sending the driver a clipped signal, it has the ability to get warmer than it should be. And you can find current without directly measuring it.
P=EI

I=P/E

squeak pretty much covered it, a clipped signal will NOT cause more heat or woofer failure, an amp clipping however, will.

remember, a 50Hz tone moves back and forth 50 times a second, whether its clipped or sinusoidal. so it gets the same amount of air cooling the coil //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

 

[BassAddictJ 5,000+ posts]

cool

now as for the smell.....after bout 30 min of hard riveing ill smell a wierd little smell and i alway let her cool down after that...im hopeing its just excess glue on the voice coils and not the voice coil themselves frying.....

 

[stones 10+ year member]

http://forum.soundillusions.net/showthread.php?t=47441&highlight=clipping
Pretty interesting. Notice that when the drivers received the same power level, but from two different types of signals (one clipped, one non-clipped), that they still failed about evenly. They couldn't prove that a clipped signal of the same power level as a pure sine wave caused the driver to fail any sooner.

The main problem with clipping isn't so much the clipped signal itself, but rather the increased power output by the amplifier while clipping. If you have a 1300w amp and clip it hard, you'll have ~2600w worth of power being received by the subwoofer.

God I've been trying to say that for ages.

Thanks for getting it into the proper words squeak.

squeak= my hero

 

[squeak9798 5,000+ posts]

cool

now as for the smell.....after bout 30 min of hard riveing ill smell a wierd little smell and i alway let her cool down after that...im hopeing its just excess glue on the voice coils and not the voice coil themselves frying.....

Are you still getting the smell 3 months later?

 

[squeak9798 5,000+ posts]

God I've been trying to say that for ages.Thanks for getting it into the proper words squeak.

squeak= my hero

:highhorse

 

[xnbastar 10+ year member]

:highhorse

lolol

 

[BassAddictJ 5,000+ posts]

Are you still getting the smell 3 months later?

nah, she runs fine now.....i keep the gains a little more conservative just in case

 

[squeak9798 5,000+ posts]

nah, she runs fine now.....i keep the gains a little more conservative just in case

Do you like check the forum once every 3 months ?