PDA

View Full Version : amp clipping



crustysack
06-03-2014, 04:46 PM
Will running larger gauge wire help stop my amp from clipping or should I go with another battery?
Kenwood -KVT 514 head unit, Infinity Kappa series 60.5 cs (4 pair components) Jl Audio 10w3v3 sub, Infinity Reference series amps a 7541a (111 watts x4) and a 611a for the sub.
The amp that runs the mids and highs will cut out at 3/4 volume for a couple of seconds then turn back on and then cut out -at this point i turn it down, the sub does not cut out. The positive wire run is about 15 ft of 8 gauge into a fused dist block,the maybe 18inches from the block to amp. The amp grounds are about 2 ft . As I am typing this it seems that bigger wire should help but its been suggested to get a 2nd battery. Running an 02 LS1 motor with a Napa 65 battery . The alternator is 102 amps.
any input with logical reasoning to back it up is greatly appreciated, Thanks

hifi875
06-03-2014, 05:29 PM
What size fuses are on the amps. 8g is only good for 60 amps of current draw. Prolly need 4g b+ and ground. Run your 4g into a distribution block to feed both amps and ground them to the chassis. A dual battery prolly won't help much. You don't really have enough stuff for that.

hifi875
06-03-2014, 05:35 PM
If you are in fact running 4 pr of speakers you prolly have a impedance problem. If they are true components w xovers then your amp is seeing 2ohm load per channel in stereo. Most high end amps can handle that but with your small wire the lower impedance causes the amp to draw more power. The amp isn't seeing enough voltage and shuts off toll the load goes away(turning the volume down)

crustysack
06-04-2014, 03:10 AM
Thanks for the reply, the amps each have dual 30amp fuses and the dist block also has 30 amp fuses- none of which have blown(not enough juice thru wire?) I will start out with the larger wire since its much cheaper than an extra batt setup. I am slightly confused on your 2 ohm load comment since the speaker sets are spec'd out at 4ohm http://www.crutchfield.com/S-WTTacYl5VOt/p_108K605CS/Infinity-Kappa-60-5cs.html#details-tab
But if it is it sounds like the larger wire will fix the problem I'll try it this weekend-thanks

alocker
06-04-2014, 03:19 AM
Hifi is on the right track but we need more info. These 4 sets of components, do they run to 1 four channel amp or 2 amps?

hifi875
06-04-2014, 06:53 AM
if you are running 4 pr of speakers on a 4ch amp then that is 8 speakers (woofer and tweeter hooked up to crossover=1 speaker @ 4ohms) then you are running 2 speakers per channel. I assume you are running them in parallel which means you are taking the two + leads and wiring them together and the two - leads and wiring them together, hence parallel. 2 speakers in parallel will drop the impedance in half so your (2) 4ohm speakers present a two ohm load to each channel of your amp. those amps should be able to handle that with the proper current. hopefully you have the internal electronic crossovers activated in the 4ch to high pass cutting all of the bass signal below say 60-80hz. that takes a lot of the load off of the amp and shouldn't cause it to draw an ton of current. As far as your bass amp make sure that if the amp has a bass eq setting or something along those lines, you either do not use it or if you do keep down low (assuming its adjustable).

scott_fx
06-04-2014, 07:52 AM
Will running larger gauge wire help stop my amp from clipping or should I go with another battery?
Kenwood -KVT 514 head unit, Infinity Kappa series 60.5 cs (4 pair components) Jl Audio 10w3v3 sub, Infinity Reference series amps a 7541a (111 watts x4) and a 611a for the sub.
The amp that runs the mids and highs will cut out at 3/4 volume for a couple of seconds then turn back on and then cut out -at this point i turn it down, the sub does not cut out. The positive wire run is about 15 ft of 8 gauge into a fused dist block,the maybe 18inches from the block to amp. The amp grounds are about 2 ft . As I am typing this it seems that bigger wire should help but its been suggested to get a 2nd battery. Running an 02 LS1 motor with a Napa 65 battery . The alternator is 102 amps.
any input with logical reasoning to back it up is greatly appreciated, Thanks

I'm assuming you have 2 pairs of components (totalling 4 woofers and 4 tweeters). A second battery will not help your situation. A battery is a storage device, not a power generating device. The only reason to run a second battery in your system is if you do extended long term listening w/o the car running. And if you do add a second battery, it's best to match the batteries. If it is an issue with power (as we'll figure out below) then your best bet is to upgrade the alternator. I had 150wpc x4 & 500 wpc x 1 in my ls1 c5 corvette running off the stock alt. ( i believe it was 145 amps though). So i'd probably look into getting something similar if you need to upgrade. (but don't do anything till we figure out the issue)

For the amp to cut out, is it going into some sort of protection mode (leds light up?)? I dont think it's a wire problem; though, 4 ga will show you a slight increase in performace (less resistance = more power).

first thing we do before you spend money is to problem solve.
step one: check to see if your gains are set correctly. http://www.glasswolf.net/papers/dmmgain.html, check your ground to make sure it's ideal, check your battery connections (ground to chassis, power to alt)
step two: disconnect the sub's amp and see if you still have the same issue. This will take the second amp, the wiring, and the amp output (well sort of) out of the equation. does it still cut out?
step three: if yes then get an iphone/mp3 player etc... and get one of these: http://www.bestbuy.com/site/eforcity-3-5mm-to-rca-aux-auxiliary-cable-cord-for-ipod-mp3/1307002483.p?id=mp1307002483&skuId=1307002483&st=3.5mm%20rca&cp=1&lp=4. this will change the input signal variable. do you still get the same result of the amp cutting out?

crustysack
06-05-2014, 02:37 AM
96888That gain setting article is good reading- I will tackle that saturday-
The amp is a four channel amp with an individual cross over for each set of components, amp is set to hp, stereo968859688696887
the sub amp bass boost is all the way down and the crossover freq (controlled thru deck )is set at 60hz and that frequency boost is set at -2.
I will get the alt specs and set the gains according to the article and get back, Thanks for all the info gentlemen:cheers:

scott_fx
06-05-2014, 10:34 PM
Let us know what you find out. Oh. And 60hz is a lot to ask of your front speakers. You may want to raise that a bit and see how it sounds. You may find you mids will handle the power a. It better. Not saying 60 is impossible, just takes more work.

crustysack
06-07-2014, 11:12 AM
I'm buying next time anyone shows up in Newport RI :cheers: Did the whole amp tone/voltage test and my gain way WAYYYYYY to high, just finished dialing in in and it sounds awesome, PLENTY of volume and NO clipping!!!! Can't thank you enough.

PT Sportwagon
06-08-2014, 04:44 PM
As other have said, go with 4 gauge power. I had the same problem. I was running a 25x2 and a 12.5x2 and the 12.5 kept starving for power. I should have realized that it was a Precision Power Pro-mos 12 high current amp. I guess it didn't like just 8 gauge feeding 2 amps.

Tim

MonzaRacer
08-10-2014, 02:49 PM
First of all if you are truly clipping your pushing the input too hard. See the input being too high pushes the electronics too hard causing it too "hit" the threshold or upper limit of the driver transistor.
Try to address power issues by reading the power consumed, but remember if the fuse isnt blowing your not exceeding the power limits if your properly fused.
I have a Marantz BP750 and it is supposed to run a 30amp fuse, but ran for nearly a month on a 20 amp fuse, till it started squalling cause it had nearly blown fuse.
Biggest issue I see with supposed experts on stereo systems have ZERO clue on how to PROPERLY design and install them. So watch out on "expert" installers.
So many are pushing large number amps but the numbers are peak numbers or conversely they push speakers with lower than amp spec rms input ratings and push drivers so far they overheat or damage drivers or amps.
After much research, training courses AND actual experiences, I find keeping 80% rule on amp to speaker ratings based on rom ratings works well and have even PUSHED that limit too 90% with decent results.
I watched many ex co workers mis match parts and pieces all with the "new" theory and technology some people decide "works".
I watch people and companies push electronics so far and so hard AND actually watched a fellows car catch fire from said "push".
Many years ago I built a girls S10 extended cab and we had all "off" brand or less than high end parts. We had over 1000W in cab and over 2500W on a bead cover that she could slide in. 2
We never had any single speaker pushed with MORE than 90% of it rms input rating or speakers combined input ratings. That trucks system ran for over 6 yrs before she had to do any major repairs.
I ran my setup in two different cars for over 6 yrs then put the amp in my truck.
I have always followed what I was taught and all of these systems function well above what we expected.
OH and that truck was set up with a 4 cyl, and ran one original alternator and 3 other alternators in semi separate charging systems, all share grounds but with separate batteries and charging cables. We used caps on all systems.
I see so many current system builders just NOT follow proper , or what I have learned proper system design and assembly.
I watch people make shoddy connections, build ground plane issues into systems and generally run high amperage cables in such dangerous places and everyone claims its ok and normal and the NEW great way.
So if an amplifier is clipping the output signal then if everything else properly rated the INPUT signal is pushing it too "clip" electronics can ONLY take proper use, otherwise you get bad results if not disastrous ones also.
So if you clip, try dialing down your input gain. if your driver(speaker) distorts you have exceeded its frequency ability either in signal quality OR quantity.
Good Luck

Nothingface5384
08-11-2014, 02:20 AM
http://www.wccaraudio.com/
more specificly
SMD Distortion Detector DD-1 (http://www.wccaraudio.com/front-page-categories/most-popular-products/smd-distortion-detector-dd-1.html)

scott_fx
08-11-2014, 09:29 AM
I'm buying next time anyone shows up in Newport RI :cheers: Did the whole amp tone/voltage test and my gain way WAYYYYYY to high, just finished dialing in in and it sounds awesome, PLENTY of volume and NO clipping!!!! Can't thank you enough.

awesome! glad it worked out!