I currently own 2 MA1200xl
• 600W Rms
• 1200W Max
• Dual 4-Ohm Voice Coils
I'm looking for a single amp to power these subs my budget is about $200-$300. (willing to spend more if i have to but will hurt the wallet FROWN)
??? By my figures i would need a 2 channel amp capable of a 4ohm load ( as 2x 4ohm DVC subs = 4 ohm load?? ), and around 1400w RMS or more??? (i dont know how close this is to being correct its just what i figured out hence the ????)
if any one knows of a good amp for me pls comment...
--------------------------------------------------------------------------------------
I would prefer not to but if it comes down to it i would be willing to try and run 2 amps for these subs as they are of decent watage
***so if anyone could suggest a good plan consisting of 2 amps to run the subs that would be great.
* now considering that there are 2 amps would i need an additional battery in the trunk or can they be on the same one under my hood?
*Using two amps would also require 2 power wires, 2 ground wires, and 2 remote turn on switches, ect.....correct??
USFLAG
Replies (9)
cplkittle on 12/17/2006 22:26:10
I would recommend an amplifier that is 1 ohm stable (all voice coils wired together in parallel (all positives together, and all negatives together) This will give you a 1 ohm load. This amp is really close to what you need:
http://cgi.ebay.com/POWERBASS-MONO-CLASS-D-2000-W-CAR-AMP-AMPLIFIER_W0QQitemZ270067104189QQihZ017QQcategoryZ18797QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
Ash on 12/18/2006 07:46:29
Running two amps isn't necessary and will only make it more expensive.
Those dual voice coil subs if wired parallel will net a 1 ohm load. Hard to find a decent class D amp to run that load without overstressing. Most are made to run 2 ohms "maximized". High current amps can do it, but will tax your electrics hard and your wallet!
If series-parallel then you will wind up with a 4 ohm load. Again, finding a amp that will net output into that load usually means utilizing a class A/B amp which still isn't that efficient and will cost quite a bit.
You may be able to find older model JBL BP.1200 on ebay for cheap. Those amp series are excellent performers and with true output. They can easily handle 2- 1 ohm loads and barely heat up.
You don't have to have all of what the subs rms rating is. 60-75% will net good results especially if the subs are running ported or lower Q values. If you stay stuck on the idea of running the exact amount, you may be limited on the amps available for choosing.
swez on 12/18/2006 13:08:08
It would be wise to choose a Class D amp that is stable at 1 ohm loads and can deliver a solid 1000 - 1200 watts RMS @ 1 ohm. This amp class is very efficient on power comsumption VS power output. (typ. ~80% eff)
It is a bit harder to find a 1 ohm stable Class D as these tend to be more expensive and generate a good amount of heat @ 1 ohms loads when pushed hard. They also consume substantial current draw at full power. (80 - 100 A's) of current is not unusual for amps in this category. So, your electrical system have to be robust enough to take strong bass hits w/o severe voltage drops.
Things to consider as you plan your way through the entire system OK?
Swez
PS A stock GM alternator for this vehicle is often the CS130 Series, 105A model. That's 105 A's at full power, > 2000 RPM. At idle, this ALT is more like 50-55A's of steady current flow. Some can get by with a larger CCA rated Battery, (700 + CCA BAT) and upgrading power lines under the hood.
Big 3 Upgrade:
http://forum.sounddomain.com/forum/ultimatebb.cgi?ubb=get_topic;f=5;t=007801;p=
MO on 12/19/2006 13:43:28
Alternators and Charging Systems
Upon reading and answering many questions about car audio, one question always pops up:
"Do I need a high output alternator or just a capacitor?"
If you want a killer system, you may think that all you need are big amplifiers and huge speakers. Not so! Adding a bunch of car audio components to your vehicle without the proper charging system may lead you to disappointment, distortion and damaged equipment.
Let's say you install a 1,200 watt amplifier in your ride. Your rides charging system must produce enough electrical current to run the amplifier and still power the rest of the car's electrical requirements. Now how do you know how much current is needed? Simple:
step 1: Find out how much RMS wattage your amplifier will produce based on the load presented by your speakers.
step 2: Divide this number by 12 (volts)
step 3: Take the resulting number and multiply by the factor below, based on the amplifier type:
Class AB: *1.4
Class T or D: *1.2
step 4: Add the totals together if there is more than one amplifier in the system
step 5: add your stock alternator's HOT current rating to this figure.
The total you get is the amount of current your car and audio system will draw at peak output.
Most vehicle electrical systems are 12.5VDC at idle, and between 13.8 and 14.4VDC above about 900rpm but we use 12 volts as the standard for these calculations because most amplifiers today use a regulated power supply, so they get 12VDC regardless of input voltage, so...
1,200 watts divided by 12 volts equals 100 Amperes of current.
If this is a class D amplifier, it'll be ~80% efficiend, so we'll add 20% of 100A to the total, and we get about 120A of current demand continuously at peak output.
This means that the electrical system of the vehicle will need to produce an extra 120 Amperes of electrical current to power your amplifier and subwoofer at peak levels. Keep in mind that the factory electrical system is designed to produce enough charging power (alternator and battery) for the vehicle's stock equipment, and was not designed to accomodate high-powered audio systems.
The biggest mistake made by consumers (and many installers) is failing to beef up the charging system to handle the extra load of the audio system. First, you need to understand how the electrical system operates. This must be one of the most mis-understood systems of the entire vehicle, so here's a brief summary:
Turning the ignition key begins the process of cranking the motor. The battery supplies the power to get things started. Once the engine is running, the electrical burden is shifted over to the alternator, and the battery then goes into a charging state, and only functions to filter and stablize the DC voltage from the alternator. The alternator uses the engine's mechanical power to produce electrical (AC) current. The AC current is passed through a rectifier and changed to DC current by the DC voltage regulator to smooth out and set the voltage rails for the car . The alternator also has the duty of recharging the battery after starting the vehicle by providing a forward bias voltage higher than that of the battery.
Everything works perfectly so long as the power requirements of the vehicle do not exceed the capabilities of the alternator. If the peak output is surpassed due to excessive load, then power will be pulled from the battery. If the alternator and battery combined cannot meet the demand, then the vehicle's voltage rails, and subsequently the electrical devices are diminished (dimming lights, spark plug misfires, audio distortion and amplifier clipping, or even the car stalling.)
The first place to look to determine if your charging system is up to the task is the alternator itself. If possible, look for the HOT RATING on the alternator. IF you can't see it easily, call a local auto-parts store or car dealership and ask them to look up the stock alternator size, or rating for your vehicle. The hot rating will tell you the amount of power the alternator will produce once the engine reaches it's operating temperature (this is a lower rating than the cold rating). I suggest using your stock alternator unless you experience problems. That's how you know if you need to upgrade, since there is no concrete way to tell if a stock alternator has enough reserve to handle your additional burdens. Now, if you do need a new and larger alternator, after finding the stock rating, then allow your alternator about 10 Amperes credit or buffer area.
For more information on charging systems and alternators, see here:
http://www.bcae1.com/charging.htm
http://www.bcae1.com/chargin2.htm
swez on 12/19/2006 16:41:16
Nice work PR... CLAP
We preach this all the time and many either ignore the advice, do a little, (But not enough) or fry a perfectly good stock alternator.
Also, most stock electricals are designed to handle all vehicle power needs and about 30-40% above that. Once we exceed this upper limit, light dimming and battery discharging problems come into the game.
Another point to consider too, at idle speeds, the alternator is only putting out ~50% of its peak output. Above ~2,000 RPM, the alternator can now put out maximum rated power. The speed of the engine determines alternator output power. One can often drop to a smaller diameter pully on the alternator and get full power at somewhat lower RPM's. This helps too.
The last item to consider is wire gage between the alternator output lug and Pos battery terminal. Most stock cars use #8 gage wire here. Yes, it's short, but #8 is rated for about 60 amperes of continous current. The same is often noted at the Neg battery post to grounding lug on the body. These wires should also be upgraded to carry more current.
FYI: Look at the gage wire that runs down to the starter. (From the Pos battery post) It's usually #4 wire or even larger. Why? Starter current draw is very high on a cold engine. (Especially during the winter months when many see sub-freezing temperatures) The engine is stiff, oil viscosity is high and it takes a good deal more current to crank the engine over.
Swez
PS Pack, care to post your comments in a stand alone post? Then we can put it in the FAQ section of this forum for others to read and link to.
MO on 12/19/2006 18:53:36
You mean MO not pack right swez ?
swez on 12/19/2006 23:14:34
Yeah, I meant MO... not Pack Rat... GRIN
Swez
MO on 12/20/2006 01:17:16
Thats better :)
Yeah i will post it in a stand alone post.
swez on 12/20/2006 23:09:33
Done deal, I installed it for you in our FAQ.
Swez
• 600W Rms
• 1200W Max
• Dual 4-Ohm Voice Coils
I'm looking for a single amp to power these subs my budget is about $200-$300. (willing to spend more if i have to but will hurt the wallet FROWN)
??? By my figures i would need a 2 channel amp capable of a 4ohm load ( as 2x 4ohm DVC subs = 4 ohm load?? ), and around 1400w RMS or more??? (i dont know how close this is to being correct its just what i figured out hence the ????)
if any one knows of a good amp for me pls comment...
--------------------------------------------------------------------------------------
I would prefer not to but if it comes down to it i would be willing to try and run 2 amps for these subs as they are of decent watage
***so if anyone could suggest a good plan consisting of 2 amps to run the subs that would be great.
* now considering that there are 2 amps would i need an additional battery in the trunk or can they be on the same one under my hood?
*Using two amps would also require 2 power wires, 2 ground wires, and 2 remote turn on switches, ect.....correct??
USFLAG
Replies (9)
cplkittle on 12/17/2006 22:26:10
I would recommend an amplifier that is 1 ohm stable (all voice coils wired together in parallel (all positives together, and all negatives together) This will give you a 1 ohm load. This amp is really close to what you need:
http://cgi.ebay.com/POWERBASS-MONO-CLASS-D-2000-W-CAR-AMP-AMPLIFIER_W0QQitemZ270067104189QQihZ017QQcategoryZ18797QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
Ash on 12/18/2006 07:46:29
Running two amps isn't necessary and will only make it more expensive.
Those dual voice coil subs if wired parallel will net a 1 ohm load. Hard to find a decent class D amp to run that load without overstressing. Most are made to run 2 ohms "maximized". High current amps can do it, but will tax your electrics hard and your wallet!
If series-parallel then you will wind up with a 4 ohm load. Again, finding a amp that will net output into that load usually means utilizing a class A/B amp which still isn't that efficient and will cost quite a bit.
You may be able to find older model JBL BP.1200 on ebay for cheap. Those amp series are excellent performers and with true output. They can easily handle 2- 1 ohm loads and barely heat up.
You don't have to have all of what the subs rms rating is. 60-75% will net good results especially if the subs are running ported or lower Q values. If you stay stuck on the idea of running the exact amount, you may be limited on the amps available for choosing.
swez on 12/18/2006 13:08:08
It would be wise to choose a Class D amp that is stable at 1 ohm loads and can deliver a solid 1000 - 1200 watts RMS @ 1 ohm. This amp class is very efficient on power comsumption VS power output. (typ. ~80% eff)
It is a bit harder to find a 1 ohm stable Class D as these tend to be more expensive and generate a good amount of heat @ 1 ohms loads when pushed hard. They also consume substantial current draw at full power. (80 - 100 A's) of current is not unusual for amps in this category. So, your electrical system have to be robust enough to take strong bass hits w/o severe voltage drops.
Things to consider as you plan your way through the entire system OK?
Swez
PS A stock GM alternator for this vehicle is often the CS130 Series, 105A model. That's 105 A's at full power, > 2000 RPM. At idle, this ALT is more like 50-55A's of steady current flow. Some can get by with a larger CCA rated Battery, (700 + CCA BAT) and upgrading power lines under the hood.
Big 3 Upgrade:
http://forum.sounddomain.com/forum/ultimatebb.cgi?ubb=get_topic;f=5;t=007801;p=
MO on 12/19/2006 13:43:28
Alternators and Charging Systems
Upon reading and answering many questions about car audio, one question always pops up:
"Do I need a high output alternator or just a capacitor?"
If you want a killer system, you may think that all you need are big amplifiers and huge speakers. Not so! Adding a bunch of car audio components to your vehicle without the proper charging system may lead you to disappointment, distortion and damaged equipment.
Let's say you install a 1,200 watt amplifier in your ride. Your rides charging system must produce enough electrical current to run the amplifier and still power the rest of the car's electrical requirements. Now how do you know how much current is needed? Simple:
step 1: Find out how much RMS wattage your amplifier will produce based on the load presented by your speakers.
step 2: Divide this number by 12 (volts)
step 3: Take the resulting number and multiply by the factor below, based on the amplifier type:
Class AB: *1.4
Class T or D: *1.2
step 4: Add the totals together if there is more than one amplifier in the system
step 5: add your stock alternator's HOT current rating to this figure.
The total you get is the amount of current your car and audio system will draw at peak output.
Most vehicle electrical systems are 12.5VDC at idle, and between 13.8 and 14.4VDC above about 900rpm but we use 12 volts as the standard for these calculations because most amplifiers today use a regulated power supply, so they get 12VDC regardless of input voltage, so...
1,200 watts divided by 12 volts equals 100 Amperes of current.
If this is a class D amplifier, it'll be ~80% efficiend, so we'll add 20% of 100A to the total, and we get about 120A of current demand continuously at peak output.
This means that the electrical system of the vehicle will need to produce an extra 120 Amperes of electrical current to power your amplifier and subwoofer at peak levels. Keep in mind that the factory electrical system is designed to produce enough charging power (alternator and battery) for the vehicle's stock equipment, and was not designed to accomodate high-powered audio systems.
The biggest mistake made by consumers (and many installers) is failing to beef up the charging system to handle the extra load of the audio system. First, you need to understand how the electrical system operates. This must be one of the most mis-understood systems of the entire vehicle, so here's a brief summary:
Turning the ignition key begins the process of cranking the motor. The battery supplies the power to get things started. Once the engine is running, the electrical burden is shifted over to the alternator, and the battery then goes into a charging state, and only functions to filter and stablize the DC voltage from the alternator. The alternator uses the engine's mechanical power to produce electrical (AC) current. The AC current is passed through a rectifier and changed to DC current by the DC voltage regulator to smooth out and set the voltage rails for the car . The alternator also has the duty of recharging the battery after starting the vehicle by providing a forward bias voltage higher than that of the battery.
Everything works perfectly so long as the power requirements of the vehicle do not exceed the capabilities of the alternator. If the peak output is surpassed due to excessive load, then power will be pulled from the battery. If the alternator and battery combined cannot meet the demand, then the vehicle's voltage rails, and subsequently the electrical devices are diminished (dimming lights, spark plug misfires, audio distortion and amplifier clipping, or even the car stalling.)
The first place to look to determine if your charging system is up to the task is the alternator itself. If possible, look for the HOT RATING on the alternator. IF you can't see it easily, call a local auto-parts store or car dealership and ask them to look up the stock alternator size, or rating for your vehicle. The hot rating will tell you the amount of power the alternator will produce once the engine reaches it's operating temperature (this is a lower rating than the cold rating). I suggest using your stock alternator unless you experience problems. That's how you know if you need to upgrade, since there is no concrete way to tell if a stock alternator has enough reserve to handle your additional burdens. Now, if you do need a new and larger alternator, after finding the stock rating, then allow your alternator about 10 Amperes credit or buffer area.
For more information on charging systems and alternators, see here:
http://www.bcae1.com/charging.htm
http://www.bcae1.com/chargin2.htm
swez on 12/19/2006 16:41:16
Nice work PR... CLAP
We preach this all the time and many either ignore the advice, do a little, (But not enough) or fry a perfectly good stock alternator.
Also, most stock electricals are designed to handle all vehicle power needs and about 30-40% above that. Once we exceed this upper limit, light dimming and battery discharging problems come into the game.
Another point to consider too, at idle speeds, the alternator is only putting out ~50% of its peak output. Above ~2,000 RPM, the alternator can now put out maximum rated power. The speed of the engine determines alternator output power. One can often drop to a smaller diameter pully on the alternator and get full power at somewhat lower RPM's. This helps too.
The last item to consider is wire gage between the alternator output lug and Pos battery terminal. Most stock cars use #8 gage wire here. Yes, it's short, but #8 is rated for about 60 amperes of continous current. The same is often noted at the Neg battery post to grounding lug on the body. These wires should also be upgraded to carry more current.
FYI: Look at the gage wire that runs down to the starter. (From the Pos battery post) It's usually #4 wire or even larger. Why? Starter current draw is very high on a cold engine. (Especially during the winter months when many see sub-freezing temperatures) The engine is stiff, oil viscosity is high and it takes a good deal more current to crank the engine over.
Swez
PS Pack, care to post your comments in a stand alone post? Then we can put it in the FAQ section of this forum for others to read and link to.
MO on 12/19/2006 18:53:36
You mean MO not pack right swez ?
swez on 12/19/2006 23:14:34
Yeah, I meant MO... not Pack Rat... GRIN
Swez
MO on 12/20/2006 01:17:16
Thats better :)
Yeah i will post it in a stand alone post.
swez on 12/20/2006 23:09:33
Done deal, I installed it for you in our FAQ.
Swez
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