car shifts weird when stereo is turned up
Joined: Jul 2007
Posts: 983
Likes: 14
From: Lone Tree, CO
car shifts weird when stereo is turned up
just wondering if anyone else had this problem with their 5at? seems if my stereo is turned up decently loud not only do the lights dim a bit when bass hits, but the trans will sometimes shift weird/downshift at lower speeds.
if so anyone know a good way to fix it?
amps im running are 100wx4 and 1500wx1
and I do have a grounding kit installed also
if so anyone know a good way to fix it?
amps im running are 100wx4 and 1500wx1
and I do have a grounding kit installed also
well done, your poorly installed audio system is causing problems for your car.
If lights are dimming that means the load on the battery/alternator is too high. You 5at uses power to control solenoids to shift (valve body,TCM ect).
If lights are dimming that means the load on the battery/alternator is too high. You 5at uses power to control solenoids to shift (valve body,TCM ect).
Registered User
Joined: Oct 2009
Posts: 27
Likes: 0
From: Balt-DC region
I'm not an expert on car stereos, but the amp draw seems real high. Even with a larger battery and better wiring it seems too much for the stock Alternator. Wouldn't a capacitor be appropriate for the 1 x 1500W?
Why caps don't do much good - the extremely short and basic version.
Let's imagine a car with a 12v battery and an alternator putting out 14v. This car also has a 1000watt amp powering some random sub.
We now add a 1 farad capacitor.
A 1 farad cap charged to 14v stores about 84 joules.
Since we have the battery sitting at 12v, the potential (usable power) of the cap is 2v or 12 joules.
We CANNOT use more than the 12 joules, since that would put the cap below the magical 12v where the battery kicks in.
In order to use the power stored in the cap, we would have to turn off the alternator, or the power it outputs would somehow have to drop - like if it's overloaded (BAD).
Note: 1 joule = 1 watt-second. 1000w for one second is 1000 joule.
Anyway, our 1 farad cap has 12 joules of power we can actually use. this translates into 12 watt-seconds. This can power our 1000w amp for 12/1000s of a second, or 0.012seconds.
This means that if we charge the cap to 14v, and turn off the alternator, we can play a single test tone of 83hz one single time before the cap becomes useless.
Since I'm not at all an expert on this, I have neglected to mention ESR and ESL, which would significantly reduce the benefit we get from the cap.
Because of ESR (ElectroStatic Resistance), an amount of power will be converted into heat in the cap. The more power you try to pull, the more heat and the less useful it is.
Additionally, the amp will convert some amount of power into heat - all depending on the amp.
In the end, the cap may give us as much as .005 seconds (single 200hz tone) of power at 1000w amp output, IF the alternator suddenly dies or for some magical reason (it's overloaded, duh) it drops it's output to 12v. If you only run 500W, it would be about 0.01 second or a single 100hz test tone.
Let's imagine a car with a 12v battery and an alternator putting out 14v. This car also has a 1000watt amp powering some random sub.
We now add a 1 farad capacitor.
A 1 farad cap charged to 14v stores about 84 joules.
Since we have the battery sitting at 12v, the potential (usable power) of the cap is 2v or 12 joules.
We CANNOT use more than the 12 joules, since that would put the cap below the magical 12v where the battery kicks in.
In order to use the power stored in the cap, we would have to turn off the alternator, or the power it outputs would somehow have to drop - like if it's overloaded (BAD).
Note: 1 joule = 1 watt-second. 1000w for one second is 1000 joule.
Anyway, our 1 farad cap has 12 joules of power we can actually use. this translates into 12 watt-seconds. This can power our 1000w amp for 12/1000s of a second, or 0.012seconds.
This means that if we charge the cap to 14v, and turn off the alternator, we can play a single test tone of 83hz one single time before the cap becomes useless.
Since I'm not at all an expert on this, I have neglected to mention ESR and ESL, which would significantly reduce the benefit we get from the cap.
Because of ESR (ElectroStatic Resistance), an amount of power will be converted into heat in the cap. The more power you try to pull, the more heat and the less useful it is.
Additionally, the amp will convert some amount of power into heat - all depending on the amp.
In the end, the cap may give us as much as .005 seconds (single 200hz tone) of power at 1000w amp output, IF the alternator suddenly dies or for some magical reason (it's overloaded, duh) it drops it's output to 12v. If you only run 500W, it would be about 0.01 second or a single 100hz test tone.
To get some perspective on how big a farad is, think about this:
A standard alkaline AA battery holds about 2.8 amp-hours.
That means that a AA battery can produce 2.8 amps for an hour at 1.5 volts (about 4.2 watt-hours -- a AA battery can light a 4-watt bulb for a little more than an hour).
Let's call it 1 volt to make the math easier. To store one AA battery's energy in a capacitor, you would need 3,600 * 2.8 = 10,080 farads to hold it, because an amp-hour is 3,600 amp-seconds.
A standard alkaline AA battery holds about 2.8 amp-hours.
That means that a AA battery can produce 2.8 amps for an hour at 1.5 volts (about 4.2 watt-hours -- a AA battery can light a 4-watt bulb for a little more than an hour).
Let's call it 1 volt to make the math easier. To store one AA battery's energy in a capacitor, you would need 3,600 * 2.8 = 10,080 farads to hold it, because an amp-hour is 3,600 amp-seconds.
Last edited by Wrathernaut; Oct 25, 2012 at 11:58 AM.
If you go on about what brands sound better, or amps that can reproduce certain sound waves more accurately, there's where some art and opinion really matters, but watts, charging rates, amps and such are all easily, scientifically measurable.
Thread
Thread Starter
Forum
Replies
Last Post