Official Car Audio Thread

[Michowski]

what kind of sub?

[Ponch]

The one in slim's for sale ad I assume.

[Tex]

yep, see slim's for sale ad, that's it.

Brand and model of sub aside, does anyone know how to hook it up to run 2ohms ??

[dentguy92]

if it is a 4 ohm sub just bridge the amp and you will be running at two ohms.
if the sub is a duel voice coil then you have may have to run the coils in series then bridge the amp...all depends on what you got....

[Tex]

Ok, thanks...I'll ask slim on saturday how many ohms the sub is.

I think I will google how to "bridge" amps or run "series" cause I don't think I'm comfortable in that area yet.

[slim]

it is a 4 ohmer.
technicly John is right, but thats not how they really do it. if your amp is 500w @ 4 ohm and 750 @ 2 ohm, you hook a 4 up to it, your gonna get 500. Even tho "internally" the amp is seeing 2 ohm. thats is why most amps have a problem running 2 ohms ( pair of 4 ohms ). altho they are getting better at making the amps play at 2 with out problems.

im running 80 watts to it, and it does just fine for out put. not gonna make ears bleed, but enough to get a ticket i spoze lol.

[Tex]

I have a RF punch single channel amp, 100W RMS at 4ohms, 200W RMS at 2ohms....I was hoping to put 200W to that JL sub.

How do I bridge a single channel amp? that's NOT possible right? you need 2 channels to bridge them together?

[slim]

yea no bridging on a mono amp.

this sub is real efficient...
doubling you power is only gonna get you 3db louder... and at a loss of dampning factor.

[Tex]

ok cool...I'll just hook it straight up normal and run 100W RMS through it. Thanks and see ya saturday slim

[Racin' Ranger1]

well ive got my box built just need to seal,carpet and wire it up. ill get some pics up later pre carpeted

[Ponch]

Anyone have feedback on Kenwood 1200 watt 12 inch subs? Heard some today at best buy, and compared to the others they had, the sounded the best.

[4wheelinrevo]

yea no bridging on a mono amp.

this sub is real efficient...
doubling you power is only gonna get you 3db louder... and at a loss of dampning factor.

thats theoretical

you need double the power or double the area (cone size) to see a gain of 3bd's.

it als takes 3db's for hte human ear to notice a difference

and yes you can bridge ANY 2 channel amp.

heres how to do it on an amp that does not support bridging, you can even do it with 2 amps if you want

in order to unders tand how an amp works you need to know that it is a push pull AC current, all an amp does is take DC and convert it to AC.

you wnat 1 amp to push and the other amp to pull (or channel) so to do it you need to run one of the maps out of phase.

basically do this take 1 RCA and put it to one amp then take the other side of the RCA and run it to a crossover in FULL mode with it out of phase, this giving 1 amp a in phase signal and the other amop an out of phase signal

then you take the + of the first amp and wire it to the + of the sub, then you take the - of the first amp and hook it up to the - of the other amp, then you take the positive of the other amp and put it to the - of the sub.

the reason that you need to put the - of the first ampt ot he - of the second amp is because both amps need to share the same ground.

FYI i have extensive knowledge in car audio, i used to compete heavily in MECA and was sponsored by a very well know company and have several trophoies to prove it.

theres not much about car stereo that i dont know

[4wheelinrevo]

Anyone have feedback on Kenwood 1200 watt 12 inch subs? Heard some today at best buy, and compared to the others they had, the sounded the best.

wht are you looking for SQ or SPL or SQL?

there is s differnet types of subs, what are you looking for?

FYI the kenwoods cant handle 1200 watts at .01 THD, they are most likely rated 1200 peak at .3 THD (THD= total hormonic distortion) the heat that 1200 watts produces cannot be disipitated by the pole vent that kenwood subs use, you will melt the coil to the pole vent.

[4wheelinrevo]

it is a 4 ohmer.
technicly John is right, but thats not how they really do it. if your amp is 500w @ 4 ohm and 750 @ 2 ohm, you hook a 4 up to it, your gonna get 500. Even tho "internally" the amp is seeing 2 ohm. thats is why most amps have a problem running 2 ohms ( pair of 4 ohms ). altho they are getting better at making the amps play at 2 with out problems.

im running 80 watts to it, and it does just fine for out put. not gonna make ears bleed, but enough to get a ticket i spoze lol.

you have to also remember are they running stereo or mono, it makes a huge difference.

4 ohm mono is not the same as 4 ohm stereo.


internally the amp seeis what the final load is, and that is determined by the subs ohms.


also to let you know a 4 ohm sub is not always 4 ohms, most likely it is DMM'd at about 3.4-3.7 and also when a sub moves from one excursion to the other excursion the impedence lowers so a 4 ohm sub in peak excursion will make the amp see about a 1.5ohm load, that is the real reason alot of amps have a hard time with 2 ohms, because during peak excursion it is oerating at less then 1 ohms.

i have actually run 1/8 ohms load on MMATTS amps


and for the love of god do not thing a capacitor will stop your lights from dimming, if your lights are dimming you have other electrical issues going on. Anyone who knows how a capaictor works will tell you that in car audio a capitor is best suited to filter out AC ripple form getting into the amps power supply.

[FreeRideFrosty]

Should anyone tell him that Slim competed as well, was sponsored, and is an audio Guru?? Or should we just wait..... Haha. Matt, IMO they are decent subs for being as cheap as they are. It all depends on what you want to do. IMO the best sub that you will get from Best Buy is an Alpine Type-R. They are a great sub for the money, hit hard and clear, and if anything are under-rated power wise. I'll keep the Brahma though.

[4wheelinrevo]

alpine type r are OK subs, they dont sound that godd, just get loud. the type X is better, hits alot lower and sounds alot better

if you want a low hitting sub get a phoenix gold RSD sub rated at 500 but i have thrown over 1200rms at it for an hour with no issues.the rsd is one oof the lowet hitting subs out right now, i was metered at 148db off of 1 12 and hit 22hz@138 which is pretty impressive, espeially since the sub costs only about $120

[4wheelinrevo]

I'll keep the Brahma though.

thats a nice sub, i would keep it too

which series you got?

here is some pcs of my SQ ride, can you guess who i was sponsored by






the alpind didnt stay long, nice sub, but doesnt do the job at all, just swaaping it out for a sponsored piece of gear gained me a few DB's







here is my SPL ride (dont have anymore as i dropped out of SPL)



heres a 9.75cf box inside the back of a ford focus




here is just a collage of some gear, if you cant tell who sponsored me then i dont know what else i can tell ya






here is my first focus show car when i was dual sponsored by MTX/phoenix gold








i first used a red top but later moved to kinetik


all 3 amps are behind plexi-glass and have neon to show case them

o yea all work performed by yours truely, most of these pics are during the final build stages and not the final with all the touch ups

[slim]

very nice!

[slim]

whats your name? i was in meca for a bit too...2003 year... got 4th at finals due to a retarded judge that gave me a 64 and the other 2 scores were 81 and 79... hmmmmm...would have got 2nd if i got at least a 77 i think it was. my average thru the year was 81 at all the shows.

[4wheelinrevo]

whats your name? i was in meca for a bit too...2003 year... got 4th at finals due to a retarded judge that gave me a 64 and the other 2 scores were 81 and 79... hmmmmm...would have got 2nd if i got at least a 77 i think it was. my average thru the year was 81 at all the shows.

my name is scott

was in meca 05 and 06, not much competting really, more of a show car.

onlu been to a couple of shows in illinois, mostly went to vegas to work the electronics show

the reason i never really got into meca too much was because, as im sure you know, there is alot of back stabbing young punks there, im was in car audio for fun, and yea to win but never had to sabatoge others to do it, it was a hobby more then anything for me.

the judges show major favoritisim at the comps, especially when you compete in SQ, they never go by the AC mic, they go by ear.

thats why i stopped, plus no more sponsor so no more dirt cheap gear
you ever go up to great lakes drag way?

the big boner in meca is the CRX

[slim]

yea i went to the grove a few times.... but got tired of paying to race and had no interest in it + the entry fee to compete... then in 04 and on EVERY show was up there so i never continued...

and your right... altho i did goto nashville and spank the home team one time...i def did not deserve the raping i got at finals, a 64... wtf come on...
i threw a fit lemme tell ya. and they had to re add all the sheets at the end cuz they cant count, i think it was a lil intentional IMO

i used no sub all year till finals and i dont think ever lost more than 1 time.

[FreeRideFrosty]

Nice! 2 Phoenix Gold guys. Haha I have one of their older 4 channel 300 watt amps that I will probably end up using to power speakers when I swap from the factory premium sound. I don't think their new stuff has the same quality of their older stuff but I could be wrong. I definitely like hearing complete systems though. Someday when I get some cash I would lover to get a full SQL system in my car.

[FreeRideFrosty]

And though a Type R may not be a great sub it is damn good for the money IMO and probably the best you will finds at Best Buy.

[Tex]

and yes you can bridge ANY 2 channel amp.

If you were referencing that statement off my questions (slims answers) about my amp, I have a (1) channel mono amp. No bridging there

[4wheelinrevo]

Nice! 2 Phoenix Gold guys. Haha I have one of their older 4 channel 300 watt amps that I will probably end up using to power speakers when I swap from the factory premium sound. I don't think their new stuff has the same quality of their older stuff but I could be wrong.

i would have to say you are wrong on this one, let me explain why.

remeber the 90's, when PG was the best of the best witht he famous MS series amp? well i have a few friends that work at PG and i have visited there portland oregon facilities

the original designers of the MS series were brought in on the new RSD series amps, thats why hte new RSD amps do not have all the bells and whistles that the xenon, and TI series amps do.

what amp do you have? it sounds like the XS series amp.

the RSD amps are every bit as good as the MS series amps are, believe me i tested them out before there release, there RSD sub is superb, it hits all the way down to 20hz and with some authority, i mean authority, the only other sub i have ever heard go that low is the PG cyclone, and as everyone knows the PG cyclone is the lowest hitting sub ever to make production