Amp hookup

Just another one of my silly questions...anyway

The amp's installed, it works and all that jazz.

It powers subwoofers. Its a monoblock amp with a R/L input. When both R/L are plugged in, it sounds ok. When I just plug the L in, it sounds like it has so much more power, but it noticeably dims my lights when it hits really hard. Do you hook a monoblock up with both channels or just one? As far as the lights, I guess I could always throw a cap in there. Any advice? I just have a bad habit of playing with things.

I suggest to go to your amps website and see if they have an online manual (unless you have the paper manual)

Yeah, of course the manual shows both hooked up. I just wondered why something that only puts out one channel anyway needs two inputs.

I'm really confused how you have a monoblock amp w/ a L and R input.

some monoblock amps are secretly stereo amps bridged
sometimes tracks have bass only on left or only on right channel... so it does this to grab both.

but it soulds like a defect in the amps phase reverse signal. basically it makes one channel (-) pull while the positive pushes as usual. it has to reverse the phase to do so. typically, negative is neutral, and positive pushes. When one chanel is hooked up, the amp goes into mono-block mode and takes the one channel and runs it to both channels.


when both are hooked up, it soulds like it's pushing as normal with one channel, as the other is not being phase reversed, so it's basically cancelling itself out...

if i would have a guess, it was a MTX? they had problems with that all the time...

also, some must use a switch if you run both channels input... so check for that (i'm sure you did)

Yeah, its a monoblock with both a R+L channel input (RCA) and only one set of speaker outs (+/-) 350x1 (4ohms) or 500x1 (2ohms). Right now its hooked up on two Infinity 1030W's @ 2 ohms. It just sounds so much better with only the left channel hooked up. Like the second channel robs it of juice, but it noticeably draws more current.

Brandon wrote:

I'm really confused how you have a monoblock amp w/ a L and R input.

It the same as JBL Bp1200.1 and them.

but i don't really know, your HU have one sub out if it does so i guess you can run it with only one input, i'm doing that with mine now.

are you running both speakers at 2 ohm each (in other words running them combined at 1 ohm), or are they 2 - 4 ohm subs that you are running in parallel to get 2 ohm? If they are both 2 ohm subs and you are running them in parallel, then you are running them at 1 ohm which is higher then the rating on that amp, and you will cause damage to your amp real quick like...

Don't you worry, they're both 4ohm subs hooked up @ 2ohms. And yes, its not an MTX (I liked my RT2120 though...) but rather a Bazooka *Ducks the hard can-like objects being thrown) EL1500. No switches, nothin fancy.

Now, it is hooked up through a pass-through adapter (Highlevel->RCA)attached to my stock speakers, not RCA's from the headunit (Stock) Would adjusting this be necessary if I could find it?

I had it originally installed years ago at CircuitCity w/ a MTX2120 and a Lightning Bolt woofer. Now I'm pushing a lot more power. I wonder if that box needs adjusting

Sublime0069 wrote:

Don't you worry, they're both 4ohm subs hooked up @ 2ohms. And yes, its not an MTX (I liked my RT2120 though...) but rather a Bazooka *Ducks the hard can-like objects being thrown) EL1500. No switches, nothin fancy. Now, it is hooked up through a pass-through adapter (Highlevel->RCA)attached to my stock speakers, not RCA's from the headunit (Stock) Would adjusting this be necessary if I could find it?

oh i know all about the bazooka el1500 considering i do have 3 of them (ducks), and i have both of mine plugged in...ive never run it without both of them plugged in, sounds silly to have one of them unplugged to me..isn't it meant to be plugged in?

Type-R - I've just decided to leave them both plugged in. I have to adjust bass/gain a bit (Almost max with two RCA [R+L]) versus very little of each (With one RCA [L]) I figure its using 14.4V on the Multimeter so its getting enough power. 6G wire should be sufficient as far as amperage. So maybe I just go a bit more deaf day by day...haha

One word... Polarity.
Since your amp has R/L on it, do you have the output wired to the speakers correctly? One easy way to tell is if you move the balance either all the way to the left or all the way to the right. If the bass gets louder on one or the other and not in the center, you have a sub out of phase.
The reason it seems like polarity to me is you stated that when you take one of the rca out of line, your bass gets louder, and when both are plugged in it gets quieter. Check to make sure subs are BOTH wired + to + and - to -.

nah... becuase an amp like that takes one signal (if it's the only one provided) and bridges it thru both channels anyway... and he said it's a monoblock amp anyway, so both would sound bad either way you had it if you had the polarity reversed.


let's get into details exactly... what amp is it? is it a true monoblock?

if not some have a reverse phase setting or pot (it'll rotate from 0-180) this would be usefull if you have 1 speaker facing in, and one speaker facing out, it would reverse the polarity at the preamp level...

Bazooka EL1500. 600W amp. 500W@2OHMS RMS, and 300W@4OHMS RMS. Only has one set of outputs, but R+L inputs. Definitely wired right. If I recall correctly, the diagram I looked at had this setup.

Isn't that parallel, giving me 2OHMS off two 4OHM subs? or should I have the sub plug separately into +/- rather than daisy chained? Amp only has gain, xover, and bass controls. Nothing else.

Manual is http://www.bazooka.com/pdf/current/el_amplifier_manual.pdf there <---

Your mono amp isnt as loud when u have both the left and right rca's hooked up because it isnt powerful enough when u have them both hooked up and it dims ur headlights because of that....you need a bigger amp for your subs, i dont know why it would get louder once you unplug one of them though, your wiring must be f-ed up....you should probally get it looked at....what wattage are your subs and amp?



__________________
1997 Monte Carlo Z34
Goldseries Underbody kit
2 12" Kicker VR comp
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800 watt rockford mono amp
1000 watt alpine amp
2 15" Liteglow Neons
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Kenwood KCD-519 Headunit
Pioneer equalizer
Infinity Kappa 6x9's and 5/1/4

"i dont know why it would get louder .... your wiring must be f-ed up"

Come "mess up" my wiring any time you want man

an amp like that should combine your signal on both... it will reverse phase, and both will cancel out eachother... sounds like a phase shifting thou...

if you had an osilliscope, then you'd be able to determin it quickly... could be the HU or the amp... anyway, just get a Y adapter and put it in 1 channel for the rca's... that should work just fine!.

The wiring was all done originally by Circuity City. They used a speaker level -> RCA converter to connect to my Ford Factory Radio/CD/Changer. The only thing I've upgraded since was the power and ground because I put in the more powerful amp. (6 Gauge) The amp produces 500W RMS (Supposedly) @ 2ohms, which is how I have it wired, and I checked that with a voltmeter. I guess I was expecting a lot more going from a bridged 100W amp to this.

Envious - No, the lights only dim if I have "ONE" channel plugged in. If both are plugged in, its fine.

Addicted - I was talking to the guy @ CC the other day and he said I'd just wreck the amp if I didn't plug both channels in, so I think a "Y" converter would do the same.

take it to Circuit City then. have them solve the problem. That's what you paid them for.

That would make perfect sense then... They have the converter wired wrong. If they have the positive to positive and negative to negative for one channel on the line converter which goes to one of your RCA's, and then negative to positive and positive to negative on the other channel (they accidently reversed polarity on one of the channels) for your other RCA, then when you plug both in, as A2I was stating, they'd cancel eachother out giving you less bass. I bet if you reverse the polarity on one of the lines going into your converter, you'd double your bass output with both plugged in, rather than cut it in half =)

CC usually talk in general and don't listen to you when you talk.

it would matter (eer... umm not really, but i'm not gonna get into it about this myth) for a 2 channel amp, but a mono amp can't tell the difference between 1 input and two... there's only one thing to push it... if anything, you'll kill the subs by having it out of phase, because they overextend the excursion of the sub by pushing eacother in favor, insead of against, as they should...

with one input out of phase on a mono amp, they will both cancel eachother out even before it reaches the amplifier circut, so no damage will be had anyway.

Yeah, CC did it for me years ago before I was confident venturing into installation. Now I've done speakers, amps, headunits, strobes, I'm not afraid of it anymore.

Mav - Yeah, like I said, with both inputs, I have to turn the gain and bass all the way up to get decent power. With only one input, I get much more power with minimal gain and bass, and it comes out cleaner.

Come to think of it, I used to have an MTX 2-Chan amp power a single sub. If I attempted to bridge the amp with both channels(L+R), it was quiet. If I only gave it the (L) channel, it was significantly louder. I just assumed that was the only way it would bridge. Maybe the polarities are wrong. I'm gonna have to tear the dash off I guess.

To make it easier (if you know which high levels lines the sub is being powered off) try pulling the deck out and cutting one set of wires and reversing polarity and see what happens..

I'm assuming the box is wired in behind the dash so yeah, I'm gonna have to pull it all out when its not 20 degrees outside. There's nowhere for them to hide the converter otherwise. I just wish I knew which colors wires were which. I've had a multitude of wiring diagrams (From putting bass blockers in) which weren't much help cauze none of the colors matched. It'll be a pain to figure out which wires behind the dash are + and - cauze you can't test em with a voltmeter either. Anyone have tips/tricks?

if you can at least seperate which pair of wires are per speaker (like if you know a specific pair of wire goes to 1 speaker, but you don't know which speaker it goes to), you can short the 2 wires acrosss a 9v battery, and the speaker will make a popping sound.

hook up the pair of wires to a battery... have a friend look at the speaker. if it's popping out, positive of the battery is positive wire if it's popping in, then the positive of the battery is hooked up to negative of the wire.

Which of course means I gotta start tearin the doors off. (At least in an Explorer, that's the only choice) I'll figure it out. Thanks guys.

or if you give me the year and model exactly, i can look it up on MAID for you not till this weekend thou!

Addicted -

Its a 1999 Ford Explorer XLT. Thanks a lot man. I've used like 3 different sites (Install DR., some site on changing speakers, etc...) and the colors were nowhere near what was in the door.

maid is commercial software for installers only. it should be correct... but the door wires might be on a different harness then the hu, and therefore the colors could be different.

Addicted --

Ok, I got the wire assignments from an installer program [WireMagic]. Upon comparing my existing wiring to the paper, the speaker level converter is hooked up to my Left Front (+/-) and Left Rear (+/-) Does this sound logical? Why would a R/L channel output be hooked up to only one side? Should I go about reversing them? <- One to a right side, one to a left?

definitely... and also have the poliarity correct...!!! sometimes bass track are only one one side or another in stereo recording...

Yeah, I'll match the polarity Guess maybe its cancelling itself when it automatically bridges L+L? Maybe that explains the output drop, and why I can't fade it at all.

Sublime0069 wrote:

Addicted -- the speaker level converter is hooked up to my Left Front (+/-) and Left Rear (+/-) Does this sound logical? Why would a R/L channel output be hooked up to only one side? Should I go about reversing them? <- One to a right side, one to a left?

And this is where Circuit City shines......

Come "mess up" my wiring any time you want man


Are you seriously ***??????
_________ ..cuz thats sick!

dude **** you.

I said come mess up my wiring b/c the post said that "it's louder, he must have messed up the wiring" or something to that effect. So I said that if he "messed" something up and it's louder, he can come mess up my wiring, thus making my car louder. So STFU

Remember. Circuit City has employees., and maybe its the install employees that suck. Ive had my local Circuit City install alarms in my last 3 cars and Ive never had a problem. ****, my camaro had a problem with the lights not flashing anymore and instead of keeping it and chragin me some BS diagnostics fee (the alarm was 4 yrs old) he looked and just replaced a fuse no charge and sent me on my way.

I went back today and the guy at the store insisted that I don't need a right channel and its ok the way it is. Don't care. Gonna change it over anyway to Left Rear/Right Rear instead of Left Front/Left Rear. Just in case some day I have a need for both channels. I'm just running it on a single L-Input now anyway. It sounds so much better.