Drudis

I've been looking around for an amp in the 1000-1200 watt RMS range, and I was wanting some opinions on if that warrants upgrading the stock alternator. I haven't had much luck with capacitors in the past, so I probably wont go that route either way. When I say 1000-1200 RMS, I'm talking Fosgate or Alpine (more realistic) wattage.
Anyone?

phlames

It can handle that with no problems.

I hate cars

You're going to get away with a lot more class D power than A/B. 1000 should be ok with either platform but it might be a little stressful with an A/B. Class D will be a lot gentler on the electrical. I had a huge A/B on my pair of 12W6s and when pushing them to their limits I got some light dimming. It couldn't have been putting out more than 1200w but being A/B it might have been drawing 2000w or more. Right now I have 1500w of class D power and no issues but my system is really efficient, I'm not using all of the available power.

You might want to look into subwoofer efficiency. I have a 92db efficient pair of 15s infinite baffle that requires very little power. I hardly use half of the available 500w to shake the car apart. You could look for an efficient large sub and go with a ported enclosure or infinite baffle to reduce power requirements by over 50% at the same output as your typical small sealed setup. There are many advantages to efficiency.

I used to look at power handling first but now I look at efficiency since you get the same end result but it's easier on the electrical system and you end up with less distortion and power compression all else being equal. Take an 87db efficient sub and a 90db efficient sub, the 90db will require half the power for the same SPL. The enclosure makes even more of a difference.

niebur3

It really depends on what frequency range you are playing? 20-80hz (subs) will drain your electrical system WAY more (like 10 times) than if you are playing 80-20k.

If assuming you are talking a sub amp, then lean toward the class D for the power. Why do you need so much power?

Drudis

Phlames: That's the answer I was hoping for.

I Hate Cars: Most of the amps I've been looking for are class D, I'm actually trying to find one thats anywhere between 900-1200 RMS@4ohms, because of the efficiency ratings as opposed to 900-1200@1ohm. I'm about to install my old subs, which aren't extremely efficient (Audiobahn AW1200q's) but they are in a large ported box (4.5cf@38hz) so the box should make up for that. Not many people know much about the efficiency ratings it seems. I learned myself when I traded my 12" Type R's for 12" Infinity Perfects. Those subs were the best I've ever owned by far. I believe they were efficiency rated at 96dB@1watt and they were much, much louder and cleaner than the Type R's with the same amp (JL 500/1). It's also the reason why I'm leaning towards a Fosgate amp, because they actually publish their efficiency ratings.

Niebur3: It's for subs so I'll be using it for 38-100hz. I need the power because I'll be upgrading my subs in the near future and I'd like to keep the same amp. Although my subs are rated at 700RMS each, Audiobahn subs are overrated in the power department.

Thanks for the input fellas.

eggyhustles

Make sure your wiring and distribution is right.

Should handle 1200 with no issues.

1200w is a lot of power?

I think i have more on tap for my front stage, lol.

OP, why do u want to roll off at 38hz? This gonna be an spl setup?

I hate cars

When did you get the JL amp? I never thought I would see the day.

I literally have more on tap for my front stage but my subs only have 500w to begin with.

I prefer a system that will play the full audio spectrum including 20hz and sometimes slightly below (not aimed at you, I think yours plays low, right?). Not a whole lot of content down there but it really adds a lot to the impact and "feeling" of the music. Several people have been really impressed with the sub 30hz stuff even before I turned it up. It's one of those things I never knew I was missing until I took my existing 12W6s and installed IB.

eggyhustles

It's my 2nd HD. Only small amp i knew of that does 300 x 2 @ 8. Gonna buy another soon to replace the dreadnought

28hz tune. Plenty of low end.

niebur3

Please say it ain't so. Audiobahn? That "A" word should be banned from all audio discussions. Please invest into something worth while. I don't care if it is new/used or whatever.

Drudis

I bought this setup years back (after 2 break-in's in my previous car) to be very very cheap but still loud. It was cheaper altogether than my previous sub amp.
2 Audiobahn AW1200's - 180
1 Rockford Fosgate 25 to life Punch 150 (1000 watt RMS) - 220
Box building stuff - 50
Wires - 40
I built the box based on manufacturer specs for SPL yes, but it's obviously not a real SPL setup. It wasn't anything to brag about but pretty loud in a little Firebird. Then the third break-in occurred but the A-hole couldn't get the sub box. So I've had these subs sitting in my closet for 4 years. Now that I drive the TL, I figured it was time to pull them out and see what they can do with a nice amp, blow them up and get new subs haha. I'm not sure there is a whole lot of activity in the 20-30hz range in most music.
You guys have some killer setups from what your signature says, but question: why in the hell would you need 1200 watts rms in your front stage?

I hate cars

Dynamics. Everytime I've added more power the SQ gets better. I think Eggy likes things a little on the loud side as well.

That sucks getting your car broken into that many times. I would be afraid to put anything in it. Good luck, I hope you have better luck with the TL.

jda123

I run 1300w at 4 ohms (D class), Audison 4.1K and Zapco 350.2... so the potential for 2600, or so watts of output. When I slam it, it will dim the lights. Unless you need to slam it all of the time, the TL will handle this. Music is dynamic and rarely takes all of that power at once...I don't like 135 db of bass anymore, though.

I have zero run to the trunk, then 4 to the T1500.1bdcp and to the Audison, then 8 to the zapco.

You will be fine.

Drudis

I lived in the dorms at UK (Go Cats!) for 2 years, and I had no choice but to park it a 1/2 mile away. So after the second break-in I decided that I would buy cheap stuff that wouldn't hurt my pockets if it needed to be replaced (even as a poor college kid). I have my own place now, but I'm still pretty paranoid about getting jacked (maybe more now since my TL is much nicer than my Firebird was).

I Hate Cars: Gotcha on the SQ thing, 1200 RMS for the front alone just seemed like major overkill (read my disclaimer below I have no clue about TL's at this point). Either way judging by your sig I bet your setup sounds better than a unicorn fart.

JDA: Why would you have a 1500 watt RMS sub amp if you dont enjoy bass over 135dB? Do you run it at 4 Ohms or something? And you have a 1500.1bdcp, 4.1k, and 350.2 with 0 guage wiring running from the stock electrical system? That is impressive.

So how many amps does the stock alt put out?

Eggy: (I've been out of the game for years) Are those JL HD amps the new version of the old 500/1, 1000/1 series amps? I mean like are they the ones rated 500 watts at 4,3,2 ohms at 12-14V? That 500/1 JL amp I had was so money, I about cried when it got stolen. Perfect SQ amp for subs.

I have to admit I've been driving the TL (which is a dark grey 04 with Navi) for about 3 months now, I'm still pretty clueless about it. I don't even know what half of the dash buttons do. And I haven't been much into car audio for quite a while, so I'm trying to catch up on what I missed.

jda123

For me? Headroom. With some amps, you need to do it with RMS numbers. I only run one sub (at 3.2ish ohms), so I need 1300 watts to get to 135db... and even then, it is not for long... maybe a song, or two.

With other amps, they slew so well, that you can get well above RMS when you need to dip in for extra power. I have some Zapco amps that at 50 watts RMS make as much "sound" as 150 JL audio watts. I have always wondered why and have heard many theories, but I don't really care.

Larger amps also run cooler, last longer and are more immune to eventual noise and distortion since they are built for more that you are putting at them.

Even with a 2K watt system, you are hardly ever pull that much for most listening - music is dynamic. You can have the battery supplement the alternator every now and then for a few minutes while you take the high output beating.

The JL HD are not like the slash. JL still makes the slash. Different, but very similar in quality and sound. Very good amps that are probably among the best of the "larger/common" manufacturers.

That 25 to life amp is no joke, but even though it says 1000 watts, it might only hit that if you try and hit like 80 hertz from all of the channels at once, or something like that.

I hate cars

The HD amps are some of the best amps period, regardless of price or brand. They pack a huge punch and are tiny. They don't have to be big because they don't have to dissipate a lot of heat due to very high efficiency. I have one under each seat which is not easy in the TL. Noise floor is practically non existent, they sound great even when pushed hard and I could not tell a difference in SQ between the JL and my $1,500 McIntosh other than the Mac has significantly less output, higher noise floor, and even though it sounded great, when you pushed it to it's limits it got harsh. The HD puts out the same power from 1.5 to 4ohm and from 12-14v. It looks like they make close to 20% more than rated power on a static load.

The goal of my system was to offer very few compromises to the daily drivability and trunk space was at the top of the list. Being able to fit the amps under the seats meant I could put the spare tire and jack back in and still have 90% of my trunk space (the 15s take up maybe 10% but I can live with that). No false floor or exposed amps.

Some people say they sound cold in the higher frequencies but I haven't noticed that and I prefer a laid back high end but still very detailed. On the other hand, many people say amps that sound warm or make a lot of sound for a given power have higher distortion. I'm not saying this is good or bad but it's worth thinking about.

xxx_busa

I agree with most the comments above, I've seen more amps than the 3 TRU billets I have, I've added the extra battery and my power control seems better, Naturally getting a beefier alternator would be nice but I've not seen any signs I must do this yet.

RBeachTL

The '07-'08 alternators are rated at 130 amp output. The car load varies; 5a DRLs, 7a fuel pump, 20a climate control fan (at max), 15a radiator fan, 10a for other lights, 15a wipers. You get the idea. One rub to this calculation is the Electrical Load Detection (ELD) circuitry. The ELD reduces the alternator output when the load is low. With all of this I think that the TL usually has about 30-50 or so amps of surplus capacity to drive aftermarket audio. You can do the math on what amp load that supports. You have to take into account the efficiency of your amp and the duty cycle of music that you listen to (the difference between sine wave power and real music power). You also need to consider the battery in that the battery will support the amp load for short periods to compensate for the demands of both the music and the car. I run 3 Zapco amps that are rated at a total of 1860W. I have to periodically charge my battery so I believe that about 1500W of A/B amp is about the limit of the stock alternator.

I hate cars

Are you basing the current of each circuit based on the fuse rating? The reason I ask is some of those seem really high. I can understand the fuse ratings since some items have a huge current spike on the initial turn-on like fans.

If I'm correct, 130a at 14v=1,820w. Looks like the battery will be helping out quite a bit in some of these systems. I never really looked at the stock alternator output before, I just assumed we had a ton of headroom but we really kill that headroom with these systems. The one thing I'm not positive on but I believe to be true is that while an AB *can* be up to 78% efficient at full volume (compared to class D at 90%+), efficiency can be below 50% at partial volume and a class D is about the same throughout the volume range. Someone correct me if I'm wrong.

I'm way too tired to think, going to sleep.

RBeachTL

The current draws for the circuits are estimates; I figured 1/3 (for lights) to 1/2 (for motors) of the circuits fuse rating. In some cases; such as the blower motor the service manual lists a power rating (240 w) so I used that.

I really don't think that the manufacturer provides us with a whole lot of electrical headroom. Like I said I know that I do deplete my battery charge over the course of a few months. One of the real problems is the ELD; it prevents giving the battery anything more than a topoff charge.

Your figures of merit for the different amp types are similar to numbers I've seen elsewhere.

I hate cars

Since my commute went from 90 miles roundtrip down to 3 miles round trip for work, I have to drive the car for a while over the weekend or it gets hard to start. My GN which doesn't have 1/4 of the electronics the Tl has, comes factory with a 120amp alternator. I'm guessing the purpose of ELD is possibly to reduce alternator load and possibly help mpg?? But at full output, what's 130a@14v, 2.4hp? You can watch it bouncing around with a scanner hooked up. With my old system, you can see it going to 100% when the bass would hit. It was a bit out of time, hopefully just scanner resolution.

So those figures you used aren't exactly "worst case" and there's much less head room than I thought.

niebur3

What is funny is I have 3 big class A/B amps in my TL capable of drawing just over 300 amps from my TL! I have a factory Alternator and upgraded under hood battery. Why don't I have dimming issues??? Just because my amps CAN draw 300 amps, doesn't mean they will ever be able to. This goes back to the frequency the amp is being asked to produce and how hard it is to produce it. To me, putting a Class D amp on your front stage for efficiency purposes is not gaining you what you think. On your subs....hell yes, but the front stage is mainly playing from 80Hz-20KHz. At 80HZ you are drawing some power from the amp, but as the frequency climbs, less and less is needed and therefore you are not gaining but maybe a few amps difference in draw from your electrical system. Now, Class D amps are smaller, so that is another benefit. However, most are still a little dirty for the front stage.

Matt, I think if I sent you my ARC SE's for a day, you would notice a difference over your HD's. I'm not saying the HD's are bad or anything, other than the slightly boosted lower end (midbass/sub bass), I actually like them and they have the size advantage . But the SE's are absolutely stunning!

I hate cars

I don't believe you. You're going to have to send me one.

niebur3

No problem. What is your addy again? Oh, and I need that darn credit card number....lol!

RBeachTL

Do you have a volt meter hooked up to the car? If not you should try it and see what happens. The TL electrical system has a lot going on. I've been on long freeway drives where I've watched the voltage drop almost 1/2 volt (from 14.1 to 13.6 V). The ELD works to minimize the alternator output and if you tap into the electrical system at the battery like everyone I know does, the ELD is not sensing the load from the audio system. When this happens you start drawing more of your load from the battery. Most of the time that's not a problem but I've seen situations where it can be.

Your specific situation might be different, I'm only relating my experience.

jda123

Could this be a year thing? My 2004 and 2006 seem to stay around 14.0 except for drops when I might slam some bass. Even at listening levels enough to do hearing damage, the stock system stays fine as long as the bass is not slamming. Is this a 2004-2008, thing or 07 and 08?

Are the arc amps bipolar or MOSFET? I might have to get one and try it. You all know that I believe (one of the few, perhaps) that amps really do matter.

niebur3

They are bipolar. I have a used 2300 and 4200 if you are interested. But yes, these are REALLY good sounding amps.

jda123

I totally believe you if they are bipolar. Send me some prices. I might buy one. Heck, I have a masterstroke that I haven't tried yet... so why not try them all. ...better put mosconi and tru on my list too.

Drudis

Thanks for all of the advice gentlemen, I'm leaning towards an RF T1500-1bdcp. It seems like it'll be perfect for what I'm looking for (that will run at 4 ohms until I blow up the audiobahns and then I can upgrade to subs that take 1000rms each, and wire it to 1 ohm.)
Any advice on subs that will take 1000 rms? I'll probably go for 15s unless I can find other 12s that will work in 4.5CF@38Hz.

jda123

There are many subs that can take 1000w RMS. You will likely need a new box for whatever you choose, but maybe you will get lucky... 38 seems a little high for most, though.

tdub206

Can anyone please help i know started another thread asking about this but i have jlw7-12 powered by a alpine pdx 1.1000 and its 1000watt stable at 2-4ohm. Im getting alot of voltage drop at the amp when the volume is turn up and bass hits. I noticed voltage drops as well at the battery terminals. Im planning to do the big 3 upgrade soon but is a high output alternator is the only amswer for my problem?

350

iTrader: (4)

What gauge wiring did you use? I would definitely do Big 3 before messing with the alternator unless there's signs it's bad. No issues here with my 800 watt Alpine MRP and 4 gauge, also extra 4 gauge grounds and a 1 gauge off the battery. You might want to look into thicker wiring from the battery to the amp. If you go thicker there, repurpose that long run into several grounds under the hood.

tdub206

Im using 4 ga awg wiring for my power and ground for the amp. Im using one of those line out converter connected to the factory subwoofer wiring with the factory sub disconnected and taken out. So that lets me control my sub level using the factory radio. Could this line out converter be bad or its putting out too much voltage?

My alpine amp has 4 20 amp fuses does it mean the max it can draw is 80 amps? So with the the factory alt at 130 amp gives me 50 amp left to to work with?

Also my alpine amp gain is only slightly turnt up maybe about 1/4 way. So im not even using near 1000 watt am i?

xxx_busa

It took 3 Ground Zero reference amp to cook my alternator, Now I have a DC power 180amp with 2 XS batteries D975 & D3400, Amps are capable of 2702 watts ea, my previous system had no strain with 3 TRU billet's....

Big 3 AND AN UPGRADED GROUND, is the first I would do, an additional battery will help with the draw.

tdub206

So i decided to take a look at the LOC, it was set at about 75% so i turned it down to 50% and turned the volume up to where i usually have it. I noticed i had to turn the gain up on the amp so its about half way now vs before it was only about 25%. I noticed that with the gain on 75% with the speaker hitting just as loud as before but the voltage drop is a little less then before.
With knowing that i just ordered a LC2I and waiting for it now.
I also went ahead and got started on doing the big 3 but the O ring terminals i bought couldnt fit in the alternator's bolt slot. But i went ahead and change out the battery negative to ground and wow what a surprise it showed improvement already. As soon as i get all stuff in i'll finish it up and post a update.

Can anyone show me where i can get a good affordable 1/0 ga 150amp fuse holder?

Thanks everyone for your help