Help me Build a s2K Sound System
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From: New Slowmyrna Beach
You are probably right, no need to make the eardrums bleed.
But why is Phil having so much trouble with 450 wrms and an 8? That doesn't seem like it would be draining THAT much power. My van has tons of power and two eights, but the van is so big I imagine it has a bigger alternator, so that compensates. But if I run the stereo for awhile without the van running, I generally have to jump it to get it started.
But why is Phil having so much trouble with 450 wrms and an 8? That doesn't seem like it would be draining THAT much power. My van has tons of power and two eights, but the van is so big I imagine it has a bigger alternator, so that compensates. But if I run the stereo for awhile without the van running, I generally have to jump it to get it started.
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From: Baton Rouge, LA
i'll tell you why! 
seriously though, class AB amps are generally 50-60% efficient. my Kicker is a known inefficient AB amp, so it's probably closer to 40-50%. i've tuned it pretty close to max excursion on the sub at high volumes - so i'm probably pulling at least 400 Wrms and 800 W peaks (peaks are when i get flickers). an 800 W peak = I amps * 13.5V. which means i'm using close to 58 amps (since my amp has a measured output of ~450Wrms) during those brief moments to provide my music... considering my amp is probably only 40 to 50% efficient, my momentary current draw may be closer to 150 amps!! (does this sound outrageous? - i think Dave's earlier calcs didn't consider efficiency... i may need to rethink this calc.).
that's WAY more than the alternator can provide instantaneously. so it falls to the battery to make up the difference... and the battery does... if i'm listening to deep sustained bass - i only get a flicker/dim for a fraction of a second right at the initial start of that note, after which everything looks normal. i'm suspecting my battery isn't reacting quickly enough due to having been deep cycled a couple times... it catches up, but it takes a moment.
and if you look at continuous draws it gets scary. still it explains why it didn't take long of tinkering w/ the stereo and the engine off to completely drain my battery... (sub 10 V)
and that's just 1 of my 2 amps...
now, class D amplifiers are much closer to 80% efficient, so they don't pull like an AB does.
now, here is where i may have goofed...
Willie -- what amp did you finally end up w/ for your sub? was it a Ti800.1 or a Ti600.2? the 800.1 is a D class... the 600.2 is an AB class.
it will also greatly matter on how agressively you set your gains... you don't have to max out your gains to get max power output, but you can roll back the gains (input sensitivity) to reduce your output to where you cannot reach max.
i've got mine set very agressively.
seriously though, class AB amps are generally 50-60% efficient. my Kicker is a known inefficient AB amp, so it's probably closer to 40-50%. i've tuned it pretty close to max excursion on the sub at high volumes - so i'm probably pulling at least 400 Wrms and 800 W peaks (peaks are when i get flickers). an 800 W peak = I amps * 13.5V. which means i'm using close to 58 amps (since my amp has a measured output of ~450Wrms) during those brief moments to provide my music... considering my amp is probably only 40 to 50% efficient, my momentary current draw may be closer to 150 amps!! (does this sound outrageous? - i think Dave's earlier calcs didn't consider efficiency... i may need to rethink this calc.).
that's WAY more than the alternator can provide instantaneously. so it falls to the battery to make up the difference... and the battery does... if i'm listening to deep sustained bass - i only get a flicker/dim for a fraction of a second right at the initial start of that note, after which everything looks normal. i'm suspecting my battery isn't reacting quickly enough due to having been deep cycled a couple times... it catches up, but it takes a moment.
and if you look at continuous draws it gets scary. still it explains why it didn't take long of tinkering w/ the stereo and the engine off to completely drain my battery... (sub 10 V)
and that's just 1 of my 2 amps...
now, class D amplifiers are much closer to 80% efficient, so they don't pull like an AB does.
now, here is where i may have goofed...
Willie -- what amp did you finally end up w/ for your sub? was it a Ti800.1 or a Ti600.2? the 800.1 is a D class... the 600.2 is an AB class.
it will also greatly matter on how agressively you set your gains... you don't have to max out your gains to get max power output, but you can roll back the gains (input sensitivity) to reduce your output to where you cannot reach max.
i've got mine set very agressively.
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From: Baton Rouge, LA
oh -- and i don't know about the yellow top... i should know more in a day or so...
if i were you, run like you can w/ the stock battery, but know where a yellow top dealer is in your area.... if you never have issues, more power to you. if you do have issues, you've done your groundwork.
if i were you, run like you can w/ the stock battery, but know where a yellow top dealer is in your area.... if you never have issues, more power to you. if you do have issues, you've done your groundwork.
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From: New Slowmyrna Beach
I'm getting two PG 600.2 Ti :
AMPS:
(2) Phoenix Gold Ti 600.2
150W x 2 @ 14.4V
(fronts)
600W x 1 @ 14.4V
(sub)
secret "Blingiest undercover mount ever" TBA with pics.
And I'm thinking about the ED12a instead og the ED10a, whaddya think? Darkknight's old sub enclosure should be big enough to take a twelve. Darkknight claimed his / my enclosure has 1.4-1.6 cubic volume. So the 12 will fit nicely with some pillow adjustment to taste.
AMPS:
(2) Phoenix Gold Ti 600.2
150W x 2 @ 14.4V
(fronts)
600W x 1 @ 14.4V
(sub)
secret "Blingiest undercover mount ever" TBA with pics.
And I'm thinking about the ED12a instead og the ED10a, whaddya think? Darkknight's old sub enclosure should be big enough to take a twelve. Darkknight claimed his / my enclosure has 1.4-1.6 cubic volume. So the 12 will fit nicely with some pillow adjustment to taste.
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From: Baton Rouge, LA
yup... i got to thinking about it on the way home... how dimming is dimming...
what i'm going on about really isn't nearly as bad as what i've seen elsewhere. is it noticable in the car? yes. if you watch the tailights when the system is full open, can you tell? yup. but most of the time, it really isn't noticable unless you're looking for it...
regarding the sub... if i had the money (very little difference in price between the 10" and 12" if i recall) and the space... i'd get the 12". just my opinion and my taste.
what i'm going on about really isn't nearly as bad as what i've seen elsewhere. is it noticable in the car? yes. if you watch the tailights when the system is full open, can you tell? yup. but most of the time, it really isn't noticable unless you're looking for it...
regarding the sub... if i had the money (very little difference in price between the 10" and 12" if i recall) and the space... i'd get the 12". just my opinion and my taste.
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From: New Slowmyrna Beach
IMO you've got a great taste, so yes, the 12 it is then.
I have lived with limited dimming in the Van, so if it occurs in the S it will only be when I am really pushing it, which is rare. I;ll push the car around corners harder than I will the amp for sure.
We will see, we will see...
I have lived with limited dimming in the Van, so if it occurs in the S it will only be when I am really pushing it, which is rare. I;ll push the car around corners harder than I will the amp for sure.
We will see, we will see...
