new sub install, need help

[PAsi]

i just installed my head unit yesterday. i have a 10" sub that i'm putting in my hatch. i ran the RCA cables and i dont have another separate amp. i dont want to hear how it wont be enough power, lemme worry about that, but i wanna know if it's possible to hook the RCA cables directly to the sub box? thanks guys and girls

[Steve02Si]

Please please please tell me you're joking.

[BlackNRedSi]

sorry PA-SI, its not really that its not Enough power, wich it ISNT enough @ all...but people are saying you shouldnt do it just becuase there is NO reason to....

its like saying, can you drive your car w/o the alternator...sure you can try your hardest, its just not going to do jack shit...

dont hook your rcas to your sub it wont do anything, just let your wires hang loose somewhere cover them up...wait for you to buy a amp!

Eric

[Steve02Si]

it's not like he's talking about hooking up the head unit's speaker wires to it. that would "work" although it's not nearly enough to power a sub, not to mention the fact that it's most likely full range and not crossed over. He's talking about using the RCA. This could very well fry the line level output of the radio in seconds. I've seen far too many people try to install things themselves only to blow sh*t up, costing them alot more in the long run! bring it to a GOOD shop and you won't be sorry. I've got a Directed 600D sub amp cheap if you're interested. I can hook you up with the shop I used to work for in Horsham if you want.

steve

[PAsi]

way to answer my question. that didn't help at all and i'm not some idiot that doesn't know what he's doing. there's a sub output on my headunit and FOLLOWING THE INSTRUCTIONS it is possible to hook it up directly to the head unit. thanks for disregarding the part about how it wouldn't be enough power and i just wanted to know if it would work. i dont exactly have enough $$ for an amp right now so i wanted to see if i could do it the cheaper way FOLLOWING THE INSTRUCTIONS. thanks

[Steve02Si]

I did answer your question. You didnt understand what I was talking about or you wouldnt have responded the way you did. if you dont even understand that you can't connect an RCA level signal to a speaker, then you should by no means be installing your own equipment. I'm not trying to put you down, simply pointing out that if you're not sure how something works, either take the time to learn before you start a project or pay someone to do it! Jeez...

[PAsi]

ok, then tell me why the stupid instructions i got with my head unit has the RCA's going directly to the sub? i'm not sayin i know everything, but i'm saying that i had the instructions to follow.

[Steve02Si]

Why dont you stop down at a shop and talk to someone. Bring your manual and tell them what you're trying to do. I'm sure they can offer you an explanation. It's alot easier when you can see the manual and the equipment being used. Do a Mapquest for Good Vibrations, 350 Easton Rd. Horsham PA 19044. The # is 215-675-8204. If it's too far from you, find a reputable shop in your area. Any installer will usually offer free advice if you ask nicely.

[Speck]

First off: PAsi, what brand of headunit is it? Lots of times the manufacturers do not list amps in the documentation or in any pictures because they do not want you to not buy the products thinking you have to buy MORE than the headunit.

As far as using RCA's: Technically, yes you COULD use them, you would need to cut the ends off and unwrap part of the wire then twist it together, I believe that the inner part of the RCA jack is the positive and the outside is the negative.

Pros:
You saved money on an amp IF it works

Cons:
Will need to replace the RCA cable when you DO get an amp.
Won't have enough power to run the voice coil of the subwoofer.. you would get SOME movement, but not enough (then again, never tried).
Could possibly damage the headunit in causing a ground loop or similiar effect sending a voltage BACK to the Headunit.

Best way to test: Use CHEAP Rca's from Radio Shack, but the ends and twist em, you should have 4 wires (2 sets), use a CHEAP speaker, not your subwoofer, hook up the POS and NEG wires from ONE pair. If that speaker gets moving and you can hear the sounds the way you NORMALLY do in your other speakers.... give it a test on the subwoofer.

I would HIGHLY not recommend this, but I sure as hell remember not haveing any money and jury rigging EVERYTHING in my car to get sound. :)

Good luck

-=speck=-

[BarracksSi]

Originally posted by PAsi
FOLLOWING THE INSTRUCTIONS it is possible to hook it up directly to the head unit.

The instructions are making the assumption that you know to run your sub with a hundred or more watts of power from an external amp. Think of the "sub" shown on your instructions as a "subwoofer system, including its outboard amplifier".

RCAs are just for feeding a cleaner, unamplified signal to your external amplifiers. Save up for a month and get a mono or 2-channel amp to power your sub.

[oogy-boogy]

Originally posted by BarracksSi


The instructions are making the assumption that you know to run your sub with a hundred or more watts of power from an external amp. Think of the "sub" shown on your instructions as a "subwoofer system, including its outboard amplifier".

RCAs are just for feeding a cleaner, unamplified signal to your external amplifiers. Save up for a month and get a mono or 2-channel amp to power your sub.

Exactly.......Please, for the sake of your hard earned $$ that got you the headunit.......Don't try what you have in mind. Besides, if you even got this to work the THD would blow your sub if you could get it up to the same level as your stocks....

[Speck]

Before it is asked: THD is Total Harmonic Disturbance. Which is, I believe, the amount of distortion or noise in the signal.

-=speck=-

[PAsi]

the sub is a pioneer 10" (ts-w254c) and the head unit is the pioneer deh-p3500

[BarracksSi]

From the description on Crutchfield's website:

"Subwoofer/Non-fading Preouts: In addition to the front preamp outputs, there is one set of outputs that may be set for "subwoofer" or "non-fading" output. When set to "non-fading", the signal is full range and the output level is user selectable from -6 to +6. When set to "subwoofer", the outputs are non-fading, and they may be set for normal or reverse phase, 50Hz/80Hz/125Hz low-pass output, and the level is user selectable from -6 to +6."

The key word there is "Preouts". That's shorthand for "pre-amplifier output", which means that the signal in that cable is not amplified enough to drive a speaker. The head's onboard amplifier section, with 22Wx4 RMS, would go to the main speakers, but is not affected by the subwoofer channel controls as described above -- it's a full-range-only amp.

The 22 watts per channel isn't bad for a head unit these days. You could get a pretty well-balanced sound if you ran just 100 watts to the sub, either by bridging a 2x50W amp or using a 100W mono amp.

What kind of box are you planning on using?

[PAsi]

i'm makin a box, my dad is a carpenter and i got plans. .85 cubic/ft sealed box

[BarracksSi]

Cool, have fun. You'll have to show it off if we ever end up at the same gas station or something. Maybe I'll have put in my system by that time, too.

[PAsi]

are you in the service? if so, which one and where ya stationed?

[2k2ep]

Man are yall drunk the 1/4 of 1 watt coming out of the rca's are more than enough to run a sub. If you want to be able to hear it though put an amp on it dumbass.

[BlackNRedSi]

Originally posted by 2k2ep
Man are yall drunk the 1/4 of 1 watt coming out of the rca's are more than enough to run a sub. If you want to be able to hear it though put an amp on it dumbass.

No shyte! we know it can run it, we arent talking about running it, we are talking about actually being able to use it like its suppost to be used...and dont be callin him a dumbass, if you want to call people that shyte, go to clubsi.com they got the aceholes over there!

Eric

[2k2ep]

Get bent, I get grief here all the time for stupid stuff like messpelling words and nobody says anything. not like this where if the rca's where suppose to actually run the subs the instructions would have told you to.

[Z26]

If you have a better pioneer unit it can be done by using the rear channels if the unit. The pioneer has a sub level filter on some units which let you run 2 fronts and and 1 sub. But in any other case the rca's will not work. It just the signal going thru them not any wattage.

[Z26]

I just did some research on your unit. It is possible to run a sub off of the rear channels. Please read your pioneer books that can with the unit. You would dissconnet the rear speakers and hook one of the channels up to the sub. I dont no how loud it would be but it will work.

[BlackNRedSi]

ok then,

i am sorry...just dont want people going off on people...not cool, but i understand what you are saying


eric

[Steve02Si]

Ok, for the last time! You CAN NOT run an RCA to a speaker! it will almost positively fry the head unit! You're confusing the head unit's speaker level signal with the RCAs. Yes, there are some radios that allow you to bridge the rear speaker signals from the built-in amp to a subwoofer, although it's still hardly enough power for a moderate sub. Understand what you're talking about before you go telling people it's possible.

[PAsi]

damn people y'all argue too much. it's not that big a deal. i have something that'll put and end to it all anyways. and it shows that i'm not a dumbass, dumbass!!!

[Z26]

ONE MORE TIME!! I am not talking about the god dam rca's. On specific Pioneer units have a low pass filter on the rear (speaker) channels. He can connect the the right rear speaker wires directly to the sub. The unit then bridges the left and right channels into one sub channel @70 watts I think? This can be done. No rca's are needed.

[Steve02Si]

Z, you and I understand this, but most of the others dont get it and trying to explain it to them seems futile. Granted, from the pic of the manual, it's worded poorly. They should specify that you can use the RCA output WITH AN EXTERNAL AMP. Still, common sense should apply there. If someone doesnt understand that an RCA can't drive a speaker, they shouldnt be installing equipment.

[Z26]

I used to sell pioneer. I used to know it all now I cant remember how to add. I work at a bank now.

[BlackNRedSi]

i understand what everyone is saying, i just give up on the whole situation...nothing against you PA-Si

[Z26]

I agree. Try to explaine hoew to hook up a home theater to a 70 year old., over the phone. When I first saw this post i started to laugh but I thought I could explaine a better way to do it.

[BarracksSi]

OK, that excerpt from the manual is interesting --

So, no, don't hook the RCAs directly to the sub itself -- you'd use them for signal to an external amplifier.

But, you CAN flip that switch, and hook the sub to the head's speaker-level outputs.

One rule of thumb I've heard is to have at least twice as much power to each sub than to either of the main channels (for example, if your mains are getting 50W each, power the sub with at least 100W). Can you bridge the sub across both rear speaker channels of the head? Doing so would give just enough power to probably play the sub loud enough to balance with the front speakers. It won't go BOOM, but it might sound smooth.

I don't see that the rear speakers would get any power, which means that you'd end up with front speakers & the sub. I wouldn't mind that setup, because I could almost care less about rear speakers.

PAsi, I'm a Marine at 8th & I here in DC, with the drum & bugle corps. I recognized your sig line -- I see it every week in the summer at the Iwo memorial.

[PAsi]

well holy shit. i really didn't mean for this to become some huge discussion. all i wanted was a simple yes or no. i dont usually trust directions but when people started getting all complicated that's all i had to go on. again, all i wanted was a simple yes or no, so i could use my sub before i get up enough $$ to get an auxiliary amp. damn, u guys overanalyze and get flustered over the littlest thing. i give up...

[BarracksSi]

The answer to the original question -- whether you can use the RCA outputs to power the sub -- is an emphatic "no".

But, apparently, you can use the speaker-level outputs if you flip that switch, which I'm guessing is in the back of the head unit. So, with that method, it's a "yes".

So, yeah, try it out that way. Like I said, it won't be heard in the next zip code, but it might sound OK.

[Z26]

No, its not a switch. Its in the menu for the setup of the unit.

[BarracksSi]

Ohhhh, ok, gotcha. I'm interested to see how well it works.

[PAsi]

thanks for the decent answer. i'm just gonna wait for my freakin extra amp. all i want the amp for is to power the sub, the internal amp is enuf for the speakers. finally, a decent answer. i'll update you guys when i get an amp...