Sub volume vs. Mids/Highs volume?

[efm80 10+ year member]

equipment as follows: 1 JL HD600/4 powering Infinity Perfects components in front and infinity kappa in rear, 2 JL HD 750/1 each powering their own 12W7, premier deh-mp780(i think thats the model number). question is why can I keep turning the volume up on my deck and my mids and highs keep getting louder. They really do not even get distorted, but start sounding so harsh you want to turn it down. But after a certain volume level for my subs they stop really getting louder. Its like they stay the same. And when I try to put my subwoofer level up on my deck at high volumes I get no added output. Why is this happening?? I dont see how I could have maxed out each of my 750 watt JL HD amps nor do I see how I could have reached max capabilities with my W7's. But then I can lower my volume on my deck and then can put my subwoofer level up with dramatic increase in output. whats going on????

thanks

eddie

Click to read more...

 

[Immacomputer 10+ year member]

You're running out of signal somewhere. You may be running out of amp, sub, or line out from the headunit.

The pioneer units I have installed have all sounded just like you're describing and some people like that. It gives them full sub output at low volumes so they can say, "like omgz itz ownly half wayz up!!!@32" and stuff like that. I believe the loud settings on the older units could help this problem.

You can try measuring the output terminals of the amp to see if the voltage increases when you start to crank it. You can also measure the pre-outs and see if there is a point where you adjust volume and you get no more voltage. If at the amp terminals and the RCA terminals you're getting a steady increase in voltage, then you're running into power compression in the subs or the enclosure.

 

[efm80 10+ year member]

running out of signal?? how would I fix that? and what is power compression again? thanks for the reply bro

eddie

 

[TurdFergueson2 5,000+ posts]

Does that HU have subwoofer controls?

 

[efm80 10+ year member]

yes it does. that is what I am talking about. When my volume is up high my subwoofer level on my deck fails to have an impact and increase output. But, then I can lower the volume and put the sub level up and have a noticable output increase. weird...any thoughts thanks

eddie

 

[Immacomputer 10+ year member]

running out of signal?? how would I fix that? and what is power compression again? thanks for the reply bro
eddie

By running out of signal, I mean that either the amps have reached the max of what they can output or that the headunit's pre-out voltage isn't increasing after a certain point. You can check this by measuring the outputs of the amp with a DMM and seeing if the voltage increases as you increase the volume level. If it doesn't increase at the amp terminal, check the voltage at the RCAs and see if it increases.

Power compression can actually mean a number of things but in this case, it would mean that as you're applying more power, the drivers can't use the extra power and so they dump it off as heat.

Another problem could be the electrical system. If your amps aren't getting the current they need, then they won't be able to put out the power you're trying to get. Those JL amps are extremely inefficient and cause quite a bit of current draw.

Before we can go any further, you need to go out to your vehicle and take some measurements with a DMM. Your problem could be any number of things and you need to eliminate possible causes.

 

[dipitydoo 10+ year member]

do you have a loudness button on by any chance?

 

[Enellz 10+ year member]

By running out of signal, I mean that either the amps have reached the max of what they can output or that the headunit's pre-out voltage isn't increasing after a certain point. You can check this by measuring the outputs of the amp with a DMM and seeing if the voltage increases as you increase the volume level. If it doesn't increase at the amp terminal, check the voltage at the RCAs and see if it increases.
Power compression can actually mean a number of things but in this case, it would mean that as you're applying more power, the drivers can't use the extra power and so they dump it off as heat.

Another problem could be the electrical system. If your amps aren't getting the current they need, then they won't be able to put out the power you're trying to get. Those JL amps are extremely inefficient and cause quite a bit of current draw.

Before we can go any further, you need to go out to your vehicle and take some measurements with a DMM. Your problem could be any number of things and you need to eliminate possible causes.

I agree with those two, I would check your electrical though first. Because though JL audio are nice I think they pull to much current for what they push. Thats why I would never buy one. So you have 3 amps running close to 1500rms right? Upgrade your electrical first with a battery in the trunk

 

[efm80 10+ year member]

I have a Kinetik 1800 up front and the BIG 3 done, do I need more?