Just a thought on batteries and charging systems.

[rockFord_Expedition]

^^^ you are correct. You can actually drop down some in capacity and still get great instant discharge power with multiple battery set ups.

Was this referring to post #59 or 60?

[iwannabeloud]

[Wood]

This info is good to know, esp since I planned to motify my plans for my system rebuild! Now I know that since my alternator should provide enough power for my situation, there won't be any need for a second battery, esp considering if I have a good front battery like the D3400 as a "reserve" in case I dip below 13v, which I shouldn't because my Singer alt is supposed to handle at least 3300 total rms on its own.

So correct me if I'm wrong, if I'm running a Crescendo BC2000D & C1100.4, my 230a alternator should produce enough to power my system properly without the need for a secondary battery?

[rockFord_Expedition]

This info is good to know, esp since I planned to motify my plans for my system rebuild! Now I know that since my alternator should provide enough power for my situation, there won't be any need for a second battery, esp considering if I have a good front battery like the D3400 as a "reserve" in case I dip below 13v, which I shouldn't because my Singer alt is supposed to handle at least 3300 total rms on its own.

So correct me if I'm wrong, if I'm running a Crescendo BC2000D & C1100.4, my 230a alternator should produce enough to power my system properly without the need for a secondary battery?

Watts = voltage x amperage

You want 3300W rms take 3300 and divide by the voltage you want to stay at. We can use 13.5 as an example. 3300/13.5=244.44.... SO that is 244amps.

A few things to consider...........

Amps aren't 100% efficient so lets say you average 70% efficiency (again just a number for an example) between your amps after all is said and done...

3300 is 70% of (approx.) 4714.

So those amps need 4714 watts of input to give you 3300w of output.

Now divide 4714 by 13.5 and you get roughly 349 amps.

So to sum it up, at 13.5V you need 349A to push 3300W out of those amps. Of course my estimates could be a little, or a lot off. But you get the picture.

4XSPower.com has a pretty nice audio calculator that is vehicle specific and will tell you what you should run. They also have a wattage chart here

[Wood]

This info is good to know, esp since I planned to motify my plans for my system rebuild! Now I know that since my alternator should provide enough power for my situation, there won't be any need for a second battery, esp considering if I have a good front battery like the D3400 as a "reserve" in case I dip below 13v, which I shouldn't because my Singer alt is supposed to handle at least 3300 total rms on its own.

So correct me if I'm wrong, if I'm running a Crescendo BC2000D & C1100.4, my 230a alternator should produce enough to power my system properly without the need for a secondary battery?

Watts = voltage x amperage

You want 3300W rms take 3300 and divide by the voltage you want to stay at. We can use 13.5 as an example. 3300/13.5=244.44.... SO that is 244amps.

A few things to consider........... to be continued

Alright I'm tuned in to the rest of your response.... But just a little background... my alternator was originally built to power a Rockford T2500 and T600-2 which estimated around 3500rms total .... The alternator ended up benching close to 265a but I always use 230a just because... with the amount of power I will be running It should even exceed 3300 hypothetically with the BC2000 only putting out 2250 and the C1100.4 will put out around 800 rms (in which majority will be head room because of my speaker choice)....

[rockFord_Expedition]

Also, remember what our H.O. alternators are rated at usually isn't taking in to consideration rising temps under the hood and other things that keep the alternator from running at optimum efficiency. So you being conservative is a good thing.

Also, on one side of the coin, on music, 3300W rms is rarely actually a true 3300W and is only so for peaks and what not

On the other side, when at full tilt are you always at full alternator RPM to make rated power?

Way to many variables to nail it down, but enough info to get it close.

I always say just get close with calculations, round up and always do a little more instead of a little less.

[Wood]

Also, remember what our H.O. alternators are rated at usually isn't taking in to consideration rising temps under the hood and other things that keep the alternator from running at optimum efficiency. So you being conservative is a good thing.

Also, on one side of the coin, on music, 3300W rms is rarely actually a true 3300W and is only so for peaks and what not

On the other side, when at full tilt are you always at full alternator RPM to make rated power?

Way to many variables to nail it down, but enough info to get it close.

I always say just get close with calculations, round up and always do a little more instead of a little less.

I understand what you're saying! And I've never had it broken down like that!!!! very sophisticated.... esp considering amp efficency which basically means the amp draws more power then its capable of putting out so therefore you have to treat your electrical as such (learn something new everyday )

Also My ORIGINAL plan was to Have a D5100R up front and a D3400 as my secondary along with my Singer 230a.... After reading this I was thinking that It would be a bit overkill for only 2k worth of sub-stage and only around 600rms worth of mids and highs, but now I know it's necessary... Thank you!!!

[GSanders17]

This thread is full of wonderful information.

[thefourth]

Good thread, thanks CJ

[Sutliff]

i got my banks cheaper than d 31s lol

Are you set up to run on just caps ... no BATTs? And I mean no BATTs in the entire car ... just CAPs & an ALT. =)