Help with subwoofers

and the chart says the series wiring will be 8Ω
 
2 4 ohm subs wires in parallel is a 2 ohm load. 2 4 ohm subs wires in series is an 8 ohm load. Subs have no impedance restrictions. Only your amp does. His amp will run a 2 ohm load. And all that dictates is the throughput of your amp. If he is at 500 watts rms because of a 2 ohm load that's acceptable according to his amp specs. As far as hitting good a few times then a thump and low volume I'm leaning towards a bad connection, bad ground, or bad LOC. 8 guage is fine for your set up.
 
Thank you Bulky, and everyone else. I'm going to bring it to the shop monday to have it checked out, I'll let everyone know of the results.
 
regardless when i do mono amps svc get done in series and dvc gets done in parallel and i never have a prob but bulkybear is right tho that its all on how the amp wants to handle it .
 
9thgizzyguy said:
regardless when i do mono amps svc get done in series and dvc gets done in parallel and i never have a prob but bulkybear is right tho that its all on how the amp wants to handle it .
Click to expand...
Why? Svc and dvc doesn't matter. It does not affect power handling what so ever. Just gives uou more options going dvc. Say you have a 1000 watt amp that pushes that stable at 1 ohm and you have 2 2 ohm single voicecoil subs. You would still be fine in parallel. Only thing going series would do in that scenario is bump impedance to 4 ohms and you would only get 300 watts or so out of that shiny 1000 watt amp :D
 
yes please lets us know i would like to know what it was but what ever you do dont let them talk you into getting a new radio ok because that info is BS they're just tryin to make more $ out of you with aftermarket stuff and labor now.

watch it be somthing stupid like a loose screw or his wires are too wirey lol :rotfl:
 
which rms and peak come into play id rather stay closer to rms then to peak because most people want power which means wire it for peak power and thats when voice coils /subs start to explode lol
 
As long as your within the power handling of the subs and not overloading your amp with too low of an impedance it doesn't matter how you wire them. If you amp is stable down to 2 ohms and you wire it down to 1 ohm load is when you have issues. And even then the amp will go into protection mode and shut off. The only ways to shred a sub are clipping the signal (gain setting is what matters here) or just putting too big of an amp on them. The peak power rating of an amp is only what the amp can put out in short burst (think of a kick drum). That short burst will not hurt subs or amp. Rms is what an amp can put out continuously. Which is why that is what you want to look. Forfet about peak power output of an amp. Thats just for advertisement. Theres no way to surpass the power rating of an amp without forcing it to go into protection mode. So with svc subs wires in parallel as long as your not over powering the subs you will be fine. The fact that its parallel doesn't mean anything other than ohm load and what your amp is putting out. Amps push power to subs. Subs don't somehow draw power from an amp. Its a one way street. ;)
 
Speakers and subs can fail from 2 things only. Mechanical failure ( driving it past it's mechanical limits, like tearing the triple joint apart, breaking the spider, etc ) or thermal failures. ( voice coil open, lead in wires burnt, distorted coil former / adhesive melting )

RMS is a theoretical figure, but it doesn't necessarily mean "continuous power forever" as in a never ending sinewave, even then a sinewave unclipped. Music typically has a large peak to average ratio, and the actual power used by an amplifier is based on the crest factor of the signal, and if it is clipped or not.

Take a look at the amperage requirements of one of my QSC amps.

1/8th power represents a musical signal that is basically -1db under clipping ( IE: full power but a clean sinewave on the o'scope, with no clipping of the peaks )

1/3rd power is music with moderate clipping, lighting up the clip lights every 1-2 seconds.

Full power is basically a 100% clipped signal, where the tops and bottoms of the sinewaves are severely clipped, basically like a square wave.

Thermal dissipation goes up as more and more current is required from the power source. PLX power requirements.JPG
 
Michael Hurd said:
Speakers and subs can fail from 2 things only. Mechanical failure ( driving it past it's mechanical limits, like tearing the triple joint apart, breaking the spider, etc ) or thermal failures. ( voice coil open, lead in wires burnt, distorted coil former / adhesive melting )

RMS is a theoretical figure, but it doesn't necessarily mean "continuous power forever" as in a never ending sinewave, even then a sinewave unclipped. Music typically has a large peak to average ratio, and the actual power used by an amplifier is based on the crest factor of the signal, and if it is clipped or not.

Take a look at the amperage requirements of one of my QSC amps.

1/8th power represents a musical signal that is basically -1db under clipping ( IE: full power but a clean sinewave on the o'scope, with no clipping of the peaks )

1/3rd power is music with moderate clipping, lighting up the clip lights every 1-2 seconds.

Full power is basically a 100% clipped signal, where the tops and bottoms of the sinewaves are severely clipped, basically like a square wave.

Thermal dissipation goes up as more and more current is required from the power source. View attachment 25172
Click to expand...
You are right. But as far as rms rating you can typically count on them in car audio as long as your not clipping the signal. Once you start clipping the signal its really easy to surpass the handling of a speaker. Especially thermal as once a signal is clipping the speakers will move irregularly and not cool how they need to. This is how I fried my first sub. But even clipping won't fry a speaker if your still not surpassing the capabilities of that speaker.
 
RMS is a calculation of the peak voltage in an ac waveform that represents the same heating capability as a dc circuit. It is calculated as 70.7% of peak voltage.

In any amplifier what really matters is what it will put out for voltage into a load, manufacturers test into a resistive load bank, typically water cooled. A speakers impedance is never a resistive load, the impedance can spike up to 80 ohms or higher at certain frequencies with some pro audio drivers that are very efficient. This is not a problem, however as the actual power across the load is reduced when the impedance is high. For example, an amp delivering 30 volts into a 4 ohm load would be ( 30x30 ) / 4 = 225 watts across the coil.

30 volts into say a 65 ohm impedance peak would be ( 30x30 ) / 65 = 13.85 watts.

Sealed boxes exhibit only one impedance peak, ported boxes two impedance peaks, one on either side of the tuning frequency, and a tapped horn can have 3-4 impedance peaks. These peaks represent close to maximum efficiency, as the speaker will deliver high output with very little actual 'power' across the voice coil.

If you know voltage and resistance, you can calculate the amperage, or any two out of the three with Ohm's law. :)
 
This is what a clipped signal would look like with moderate clipping, the tops of the peaks are cut off.


tweak_clipped.gif
 
Here's a severely clipped signal displayed on a scope. The bottom one has severe asymetrical clipping, where only one rail is clipping, this is not typical of a good amplifier and a clean signal. It's basically showing that you are 'running out of gas' in the amplifier.

This is a dual channel scope, generally you would view the signal going into the device on one channel, and the output on the other. ( bottom of the scope )
clip.jpg
 
So I went to the shop this past Monday, and they told me that it's doing this because the amps are hooked up to the speakers and not the radio. That's why they told me I should get an aftermarket radio because it has the rca output. So my question is, the 13 honda civic's factory radio doesn't come with rca outputs?
 
arter said:
So I went to the shop this past Monday, and they told me that it's doing this because the amps are hooked up to the speakers and not the radio. That's why they told me I should get an aftermarket radio because it has the rca output. So my question is, the 13 honda civic's factory radio doesn't come with rca outputs?
Click to expand...
It doesn't. And that coincides with what I was talking about when I mention to much voltage to the inputs of the amp. Most line out converters have an adjustment so you can dial back the output voltage. You need to tell them to quit trying to sell you another product snd make your setup work properly. I know it can as I've done it.
 
Bulkybear said:
It doesn't. And that coincides with what I was talking about when I mention to much voltage to the inputs of the amp. Most line out converters have an adjustment so you can dial back the output voltage. You need to tell them to quit trying to sell you another product and make your setup work properly.
Click to expand...


:yeahthat:

Get it fixed and never go back to that place.
 
hes done it ...hell my si has been like that over a year and no probs so they are full of shhiizzznick !
it looks like you need to go somewhere else and get it done right my friend .
 
You must log in or register to reply here.
Back
Top