Starting the 2nd stage, looking for advice

[LetMyBeatPound]

Hey guys long time no post, lol.

Anyway just a recap, I got 2 FU750v2 18s in a 32hrz tuned 14cf box, powered by an Alphard Machete M2000D and 2 100aH batteries. All ran with 2/0 ofc welding wire. N 8g ofc welding for the speakers.

This is where I start needing a bit of advice, I'm getting an Excessive Amperage 300amp hairpin alt, reconning my subs, add 4g push terminals instead of the 8g, maybe add 2 more 100aH batteries I'm not sure yet about that.

What I would like to know is with that alternator, he says I'll get around 220 amps at idle, is this enough to power my set up and charge the batteries?

I'm trying to find a fabricator to make me a dual alternator bracket n run the stock 90amp n the 300 but that will most likely come later maybe even use 2 300amp hairpins when I do it.

I also need to get a new HU, because not only is it broke n breaking more, it intermittently cuts in n out on the right side and other things like only 3band EQ n it only has 1 RCA output n it's got crappy power for it output signal. I also need new 5.25 dash speakers, not looking for anything crazy just a place holders till I get the PRV Neo mid range n mid bass speakers at tax time.

I know that's a lot but just would like a few HUs to check out, I got about $200 budget for it more if it's a good one. I was thinking 80prs but idk

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[LetMyBeatPound]

Just for lil more info on where Im going with my build is after upgrading the electrical and trying to improve my signal now, I will be doing an active 3way front stage at tax time with PRV 5.25 neo mid ranges, PRV 8" midbass, and some Crescendo silk super tweeters, a fosgate DSR-1 dsp with 2 1000.4 amps of some sort. And probably add a 5th or 6th battery when I do all that

 

[Jeffdachef 5,000+ posts]

80 prs if you can, if you cant then jvc 340bts will do just fine and its 80 bucks. I can attest that that JVC will hold its own against the 80 prs for the most part.

As for your electrical, we wont know until you see voltage drops.

 

[winkychevelle 10+ year member]

Electrical wise you should be fine that amp is what 2500rms if so it prolly draws 250-275amps of current on a sine wave. You shouldnt be dropping voltage that bad now eith 2 100ah batts. Yea youll drop to 12.8 but then it should pretty much hold there.

Are you wired below 1 ohm? Or are you wanting to add a bigger amp? What are your actual goals?

If it's to stop dimming, led or hid headlights will do it for far cheaper. If it's just to built a stout electrical the 300a alt and 2 100ah batts should be sufficient.

 

[LetMyBeatPound]

Final goal is 4 18s. I'm also getting I forget the name but it's a Bluetooth SPL meter. I want to make a 3-1 4th order but someone told me with out a meter to check resonat freqs that I'll will probably make a crappy box so I'm ordering a meter. Than n because it's $50 for 3 1minute runs to get metered at a local place. Want to be able to hair trick. So I'll have a active 3way front stage very similar to what JeffDaChef has I believe, he's the one who told me about how I should set it up. Idk what I should do to power the 4 18s... But that's is probably done in may/june. And yes I have em wired at 1ohm

 

[winkychevelle 10+ year member]

Add the alt add 1 more batts and see if it can support the 2 2000w amps. On music I suspect it would be fine but competing on the meter or long demos full tilt you may need the 2nd alt or at least the 4th batt.

My general rule of thumb is get the most alt possible at least 50% of amp fuse rating plus what the car needs and 100ah of batter for every 100ah of fuse rating on the amp.

 

[LetMyBeatPound]

The plan is to add the HO 300amp/220@ idle hairpin alt.

Replace my cheap HU, (only 1 low voltage output) with either a 80prs or the other HU Jeff said.

Add 2 more 100aH batteries (total 400aH+60aH from start battery)

ReCone both my FU750 18s.

The first day I got everything hooked up, I stunk up the subs causing them to have mechanical/scraping noise at low volume n loose their crispness at higher volumes. I think this happened because of dirty power running through everything because my stock alt is like 40-50amp at idle. I have seen videos n heard of people putting 1000w to 1500w per FU750 without issues. So I don't see how I damaged mine with a 2000w amp ran at 1ohm pushing both of them any other way.

So I'll finish my electrical with the HO alt already have big 4 done in 2/0g ofc welding cable. My batteries are even grounding back at the start battery. And I have 8g ofc wire for my speaker wire. I am also upgrading the terminals from 8g to 4g push terminals on the subs them selves. Hopefully this will make them able to get all the good clean power they want.

Does this all sound like I'm headed in the right direction with my build?

After I finish my front stage at tax time, in May I'll get 2 more 18s, have a dual alt brackets fabricated, and build a 3-1 4th order wall build and either add another M2000D or try to find another set of 2500-3000rms amps.

 

[Papermaker85 5,000+ posts]

Pics bro!!

 

[LetMyBeatPound]

Pics bro!!

https://imgur.com/gallery/Q6Zy3

Here ya go PaperMaker I have a box that the batteries that's not shown because I used bedliner spray on it n just haven't had time to put it back in. I havent painted it or anything be cause when I recone them, I'll pull the box because I have to add 45s in the corners and put a few new T-Nuts.

 

[staan]

The first day I got everything hooked up, I stunk up the subs causing them to have mechanical/scraping noise at low volume n loose their crispness at higher volumes.

more likely a distorted signal than voltage drop caused this.

 

[hispls 5,000+ posts]

The first day I got everything hooked up, I stunk up the subs causing them to have mechanical/scraping noise at low volume n loose their crispness at higher volumes. I think this happened because of dirty power

So the issue is "dirty" power as opposed to running two 750W subs on an amp that makes > 2500W?

Carry on. Batteries and alternators will totally make that 2.5" coil hang with 1200W+

 

[LetMyBeatPound]

How do you figure 2500w. it's 2000w RMS, @ 1ohm @ 14.some volts, plus it's an older amp technology n is not as efficient, and my van barely makes 13.2v no mater my rpm ... Figure like 1600w to 1850w at best in my situation. Frank if FU Audio just shared a FU750 12s video with 4x FU750s in 6k full tilting no problem

 

[hispls 5,000+ posts]

How do you figure 2500w. it's 2000w RMS, @ 1ohm @ 14.some volts, plus it's an older amp technology n is not as efficient, and my van barely makes 13.2v no mater my rpm ... Figure like 1600w to 1850w at best in my situation. Frank if FU Audio just shared a FU750 12s video with 4x FU750s in 6k full tilting no problem

2.5" coils are rated at 750W for a reason, but again, carry on. m

 

[LetMyBeatPound]

Either way I still need to upgrade the alternator and HU. Especially the alternator since I plan to add more stuff.

And I'm not making no where need 2500w with this amp, that's a rediculous statement, 40-50amp alt n 260aH of regular refurbished lead acid batteries isn't supplying my amp with nowhere near the 200-240amps it wants. It's rediculous to try and say differently. Between my 50amps my alt produce n the maybe 20-24amps my Batts produce gives me 74a multiplied by 13.2 gives 976.8 of max wattage my current electrical system can supply. There's no way I hurt my subs over powering them. It's pretty simple math, even if you take all my components and use the best possible outputs it's still less than 1200w max capability

Edit: and that don't even account for the needs of my vehicle...

 

[Jeffdachef 5,000+ posts]

you system wasnt capable of making clean watts. However, If you force the amp to do it, ti'll make more power but it'll be clipped power. If the subs stunk then its actually you cooking them with a dirty signal. Thats caused by voltage drops or dissatisfaction with output which leads to overdriving the amps and not even noticing. So you were actually making that amp's power but clipped. Even a boss amp can make power when clipped.