Flooded and AGM together?

[ciaonzo 5,000+ posts]

I appreciate all the input, guys. I don't normally run big power so I'm not up to speed on all these high amperage additions.

Alright, so I'll get past the fuel economy thing and source a proper HO alt. From there, I like the idea of an additional run for the grounds. I may do two runs each of 1/0 for + and - just for good measure. Okay to do that? Just run ground straight from the front battery rather than just finding bare metal somewhere in back? Beyond that, I think I'll try the AGM/ultracaps combination in the rear.

 

[hispls 5,000+ posts]

I'd just add an extra AGM or two (one 110AH or 2 55AH size) would be plenty to support class D 3K amp.

Apart from db drag type applications, caps will not do you any favors, you'd do better with your money investing in alternator, lifepo, or just buy amps with regulated power supply.

Even if weight/space is a top concern, just HO alternator without upgrading under the hood bat is probably not going to be optimum.

In short, adding AGM batteries are the most bang for your buck all around (replacing primary with AGM when it starts getting weak down the road). HO alt and lifepo are expensive "upgrades" to this strategy when you want to trade money for weight/space.

I personally never used isolators and I don't think they were that popular even when they were a meme. For practical purposes, it isn't as though anybody plays with engine off for long periods, and at today's power levels, if you wanted to, your battery bank would be so big that it wouldn't matter.

Can't wait to see what you do with the power upgrade. Your access to killer subs seems limitless.

 

[LosIsATool 5,000+ posts]

The last thing I'd do with a struggling electrical system is putting regulated amps on it.

 

[hispls 5,000+ posts]

The last thing I'd do with a struggling electrical system is putting regulated amps on it.

The point was to drop money on that before caps if you're worried about dynamic peaks in music.

I'd be more verbose but I got my arm badly broken and typing one handed is slow going.

Also, for most situations running ground all the way front won't be any benefit.

 

[ciaonzo 5,000+ posts]

I'd just add an extra AGM or two (one 110AH or 2 55AH size) would be plenty to support class D 3K amp.
Apart from db drag type applications, caps will not do you any favors, you'd do better with your money investing in alternator, lifepo, or just buy amps with regulated power supply.

Even if weight/space is a top concern, just HO alternator without upgrading under the hood bat is probably not going to be optimum.

In short, adding AGM batteries are the most bang for your buck all around (replacing primary with AGM when it starts getting weak down the road). HO alt and lifepo are expensive "upgrades" to this strategy when you want to trade money for weight/space.

I personally never used isolators and I don't think they were that popular even when they were a meme. For practical purposes, it isn't as though anybody plays with engine off for long periods, and at today's power levels, if you wanted to, your battery bank would be so big that it wouldn't matter.

Can't wait to see what you do with the power upgrade. Your access to killer subs seems limitless.

All great points, I appreciate the experienced input. Especially with that broken arm. A speedy recovery to you.

 

[wew lad 5,000+ posts]

Apart from db drag type applications, caps will not do you any favors, you'd do better with your money investing in alternator, lifepo, or just buy amps with regulated power supply.

i mean in theory maybe, but with a banda 7k and i can only assume other brazilian amp toplogies with lower internal capacitance ive seen a major improvement in loudness and voltage drop (2v) with simply adding one bank of caps. i clamp 450a of draw fwiw. i see a lot of value in caps, pretty sure you've said or agreed that music isn't just a bass line, it's very dynamic. i do get lower voltage after long current draws compile with the need to charge the caps but its nowhere as bad as you hear about

 

[audiobaun 5,000+ posts]

Thanks, guys. I hear you, a couple batteries does add up to a bit of weight. I was thinking more along the lines of how the alternator is harder to turn and eats up a bit of horsepower, fuel economy in that regard. Those lithium batteries are so pricey, though. I almost want the bank of ultracaps just for that reason. Perhaps an AGM in conjunction with the bank of caps? Seems like it would address both the tones and the dynamics, sustained amperage from the battery and bursts from the caps?
I know that is a gross oversimplification but is the concept sound?

I can see multiple batteries of 4-8, but two batteries in my CRV(AGM Super Starts,one under the hood and one in rear ) didnt seem to make any difference on mileage or real weight gain that I could tell on approx 2300 rms with all 3- amps and ELD By-pass

 

[hispls 5,000+ posts]

i mean in theory maybe, but with a banda 7k and i can only assume other brazilian amp toplogies with lower internal capacitance ive seen a major improvement in loudness and voltage drop (2v) with simply adding one bank of caps. i clamp 450a of draw fwiw. i see a lot of value in caps, pretty sure you've said or agreed that music isn't just a bass line, it's very dynamic. i do get lower voltage after long current draws compile with the need to charge the caps but its nowhere as bad as you hear about

I'm very confident that the 280$ you paid for those will hold a lot more energy spent on a decent AGM. Not saying they don't have value, just that they just can't store as much energy as batteries. Bass Race vehicle that lean on caps fall on their face.

Music is dynamic, but some is basically test tones, same as your "half ohm" woofer load may actually blow your 1 ohm stable amp, or your amp may never see under 3 ohm. You won't know without proper testing and a basic understanding, and it is good to err on the side of caution.

Without such testing AND driving around with someone a lot to see what and how they listen we really can only guess and generalize what may or may not work.

 

[wew lad 5,000+ posts]

I'm very confident that the 280$ you paid for those will hold a lot more energy spent on a decent AGM. Not saying they don't have value, just that they just can't store as much energy as batteries. Bass Race vehicle that lean on caps fall on their face.
Music is dynamic, but some is basically test tones, same as your "half ohm" woofer load may actually blow your 1 ohm stable amp, or your amp may never see under 3 ohm. You won't know without proper testing and a basic understanding, and it is good to err on the side of caution.

Without such testing AND driving around with someone a lot to see what and how they listen we really can only guess and generalize what may or may not work.

absolutely agree from an energy density standpoint, from the standpoint of stabilizing voltages i dont see them being beat by anything other than lithiums which inherently have higher capacitance. having the charging capability to fill them back up is the most important thing, so i think we're on the same page

 

[ciaonzo 5,000+ posts]

Ultracaps must have pretty low ESR to go along with their very respectable ability to pass current, so putting a bank of caps between the amplifier and an AGM or lithium in the rear (fed by the HO alt) should satisfy both tones and music. The caps can discharge/charge very quickly for music, quickly replenished by the neighboring battery. If tones, then the caps would obviously dump but the battery would be there to sustain the current draw.

I'm about 50/50 for tones and music. I don't do shows or compete so I'm simply looking for reliability and a noticeable difference in dynamic performance.

 

[hispls 5,000+ posts]

absolutely agree from an energy density standpoint, from the standpoint of stabilizing voltages i dont see them being beat by anything other than lithiums which inherently have higher capacitance. having the charging capability to fill them back up is the most important thing, so i think we're on the same page

Which is true but that comes back around to just buy amps with regulated power supply for the premium price as opposed to weak power supply and external cap bank.

I think we've pretty well hashed out the strengths and weaknesses of each option. Everything is a compromise and any combination can be effective for most applications.