Thanks for checking this out... Kinda need some help here.
I just bought 4 Audiobahn Immortal Awis12p's and I'm planning on powering them with an old 1996 PPI a1200 606.2
Now the old PPI i'm pretty familiar with... except for the old bridging connections. If i remember correctly, i can bridge the amp to 0 ohm stable, and run the speakers series. Only a few minor glitches in the whole scheme....
1) I cant remember which way to bridge the amp to 1 channel mono. -there is also aold rumor about PPI amps that you can juice them up to 18+ volts to increase the output. ( true/false?)
2) I haven't built the box yet - Need specs, audiobahn page doesn't allow access to specs, only lame advertisments.
Plan to use 1"mdf for the whole enclosure, the trunk allows for a 36"lenght x 26"wide x 14 1/2 tall (outside dimensions)
That's roughly 3.4 cf. for 4 speakers? (non ported box)
3) Surely don't know anything about the new quad coils, how to divide the oms per terminal, much less, how to even hook them up properly. Unless i only use one terminal, but where's the fun in that?
4) Is this PPI amp even strong enough to run all 4 of these?
If not what size amp(s) should i consider. Even tho that
PPI is selling for 800.00 on ebay right now. ( for good
reason That amp WAS a killer back in the day.)
Lastly, if at all possible, whats the best connections/box type -series / parallel / both? Whats the best type Isoberic / ported / sealed / bandpass?
** My Goal on the amp is to run the gains at 80%, that should power all 4 speakers somewhere between 500-600rms each, i realize this is low, but it should produce cleaner bass IMO.
The head Unit - 2005 Alpine cda9835
The Rear Speakers are Audiobahn AS69V (4 on back deck)
- Powered by Punch 200aiv (crossover in head unit)
Door Speakers/satellites -JL Audio XR653-CSi
- Powered by PPI a600 (1995 model)
Any help would be greatly appreciated!
Thanks
PPIJunkie!
Replies (12)
PPIJunkie on 06/14/2006 01:13:56
http://www.audiobahn.com/Audiobahn06/images/tech/2005.html
closest page I can find for Box Specs
ttocs on 06/14/2006 03:46:07
"Now the old PPI i'm pretty familiar with... except for the old bridging connections. If i remember correctly, i can bridge the amp to 0 ohm stable, and run the speakers series. Only a few minor glitches in the whole scheme.... "
all amps are stable at zero ohms...... with 0 watts output....
newB on 06/14/2006 04:14:46
yeah that caught my attention when i saw it... isnt that a short?
-Drew
PPIJunkie on 06/14/2006 10:14:12
Kinda the point. not too sure how to wire this thing together. I'd really prefer not to start a fire in the wigwam if ya know what i mean.
any help would be greatly appreciated.
swez on 06/14/2006 10:18:27
We need to get a manual for these PPI amps. Best thing to do, is contact PPI and ask for the install manuals for both amps. Once you have these, we can help you figure out what to do next.
To go further w/o the manuals is pure guess work and we don't want to see you wind up damaging your amps. These amps were built very well, but no amplifier can handle a ZERO ohm load. (Dead short to outputs)
One ohm, 1/2 ohm stable amps are possible with High Current topology amps. However, if these amps are not HC amps, they cannot take ultra-low ohmic loads w/o damage.
http://www.precisionpower.com/contact/default.asp
Swez
MrBrownstone on 06/14/2006 13:36:30
PPI Junkie
Sounds like you are coming out of retirement with those amplifers !!! :-) I haven't heard the A1200 or A600 in years.
Concerning how you operate your equipment, we may want to break it down in sections. Speakers, power, enclosure.
In the case of your woofers, there's no way in hell those woofers are designed to perform in a sealed enclosure. Also, they'll need 1000W each to operate effectively. And lastly, they are SPL woofers...are you at all concerned about the sound quality? if not, they're perfect! GRIN
Concerning amplifiers, there's only one type of amplifier that can efficiently supply power to those woofers, and that's a Class D. You need 1kW per sub, period. Otherwise, you'll be disappointed.
The box...well, are you ready to give up 1.5cuft per woofer? after displacement?
From there, we'll determine if you can even use these subs or amps in this configuration
MrBrownstone on 06/14/2006 13:39:28
PS I have a master's degree in Art series amplifiers...:-) You have 300Wx2 or 1200Wx1 @ 4 ohms.
You can run them 600Wx2 @ 2 ohms...but expect the heat to be something similar to a barbeque grill if the load is any lower. That amplifier is really best used @ 4 ohms mono on woofers.
They were great products for their time, and probably the best ABs running for 6 or 7 years...but a lot has changed.
PPIJunkie on 06/14/2006 21:33:09
Sounds like you are coming out of retirement with those amplifers !!! :-) I haven't heard the A1200 or A600 in years.
- Yes retirement is now an issue of the past....
- my brother talked me into putting a system back in the jalope.
Concerning how you operate your equipment, we may want to break it down in sections. Speakers, power, enclosure.
-speakers are 2/4 AWIS12P AudioBahn 12's. (Immortal Series)
Power, Awesome Question. Not too sure if what i have is enough
1996 ax606.2 and a 1995 a1200. Those are the 2 Amps I Intend on using. Whether it be one or both.
In the case of your woofers, there's no way in hell those woofers are designed to perform in a sealed enclosure. Also, they'll need 1000W each to operate effectively. And lastly, they are SPL woofers...are you at all concerned about the sound quality? if not, they're perfect!
-Sealed Enclosure? Thats all i know about! Ports? WTF are those.. lol kidding, the specs call for a 4x11 port. How I will break that up i'm not too sure yet.
3 options:
1) can do 1 port @4x11
2) can do 2 Ports @ 4.5x4.5 (divided chambers) (increase resistance to 5% or so. compaired to 20% at 4x11)
-site claims it helps.. true/false I'm not sure.
3) Run them Free Air, If that's EVEN POSSIBLE! ( thats the best SQ install IMO. These boxes don't cut it for me. Bass is too Pingy, and tight. like Looser Lower bass but yet powerful.
SPL Speakers? Seriously just not hip on the terminology.
My extent of installs is hiding wires, putting in head units, amps blah blah... and some intermediate wiring. Bridging, running series, parallel, isoberic,or just + to + and - to -.... Push Play.
I still don't know how to break the ohms down, or what is better.
To answer the question, sound quality is somewhat important. I have all my High's and Mids set perfect. Every beat/clash/is SUPERBLY Crisp. I would hate to ruin that by some lame sounding subs. It would be more important to me to have lower end subs with better quality, than to have 5 million watts in the trunk.
Concerning amplifiers, there's only one type of amplifier that can efficiently supply power to those woofers, and that's a Class D. You need 1kW per sub, period. Otherwise, you'll be disappointed.
Again not too sure on what my PPI amps are, Class D? RMS/peak, Can I bridge it to 2 Ohm mono? Can I Over Power them ( did that already 18v to each amp. ran a lil warm but otherwise no worse for the wear.) I thought they were. But, again my lack of knowlege in the dept makes me a little uncertain.
The box...well, are you ready to give up 1.5cuft per woofer? after displacement?
yeah what ever I have to lose to get these in the trunk is fine w/me I haven't opened the trunk since i put the 6x9's on the deck.
My basic problem is
1) is it sufficient power
2) how the sam hell do i wire these new types of speakers with multiple voice coils. And with the amps, Even if i bridge them to 2ohm 1 channel, how would i run them series or parallel?
3) The Box, the raw truth about limiting the port sizes to alot for breathing, can it be reduced by a %, to change the performance of the speakers?. the basic hook up is simple (power to amp)
Prob lies withing the Amp to the speakers. ( mainly the speakers). 2 sets of terminals and no clue what to do with them.
Do I run 2 amps to one speaker?
or do i run one anp to each speaker?
or the 2000 RMS means I can run 4 500/1 mono blocks to each one? this is the confusion i face.
I appreciate all the responces greatly.
I have contacted PPI and ordered the manuals today. be here friday.
- PPI Junkie
MrBrownstone on 06/14/2006 22:39:12
Why don't we look at just one thing at a time...the woofers.
Although the salesman (or Audiobahn) may have told you otherwise, these woofers are designed to reach maximum loudness...and waste a lot of power in the process. Although we can help you, plan on buying a different amplifier for best results. However, as we are making due with what we have....
Box
These woofers are made for a vented (ported) enclosure. Because of their stiff suspension, the 1st 25-50W or so are basically going to be wasted overcoming the suspension. Until you get to about 100W, you aren't going to hear the entire audio spectrum...and likely 200W.
Audiobahn recommends VENTED:
Everyday Driver
3.0 cu ft gross (2.3 net)
2-4" ports 15" long
Ultimate SPL
4.0cu ft gross (3.4 net)
2-4" ports 10" long
Essentially, the amount of space you were going to alot for all 4 woofers is what you need for EACH woofer?
Honestly, can you return 2 of them? or do you have 10-12cuft for this design?
swez on 06/16/2006 13:03:33
Frankly, many of us here know the value of less is more. Having 4 subs of this design, requires a very large enclosure, a huge amount of power to run the amps to rated potential and major electrical upgrades to go with the package.
If you are planning to compete it SPL Comps, then consider this a long term project with much $$$$ to be invested. However, if you wish to enjoy strong bass and skip all the added work, expense and loss of space, 1-2 of these subs are more than adequate.
Say more on which way you wish to go.
Swez
PPIJunkie on 06/19/2006 12:13:02
I have made the decision that I'll only use 2 of the 12's. And the 2 PPI amps. Balancing the power from the amps shouldnt be too hard tho, if i seperate the compartments for each speaker. yes/no?
ax606.2 and a A1200. Same thing except the Ax606 has a Xover in it.
the Amps and the wiring are the hard part. These have quad coils. So i'm wondering how the connections are.
1) got the specs on the amp to bridge them both down to 1 channel each. so each speaker will get roughly 1200 w RMS.So i'm hoping i should be able to turn the gains to 75%-80% and utilize the power of the amps as best as possible. without distorting too much.
2) the series/parrallel. which one or both?
Speakers can go to .( ?? Im guessing any ) ohm. but the amp is bottomed out at 4ohm mono. anything lower than 11 volts, or 4 ohms will trigger the the protect circuit.
Amp Stats are.
power Bandwith 10Hz - 50kHz
THD 0.02%
Input Sensitivity .2- 2.5 v ( my H/U has 5 V PreAmp out... that a problem?
Input Imperdance (stereo) 2-8 ohms
Load impeadance (bridged) 4-8 Ohms.
Supply Voltage 11-18v
Then there is the wiring. I know the amp wiring, but the speakers..... Whats the best way, JLaudio.com has a chart that gives the Diagrams for changing ohms, and wiring choices. But which is the best way for these amps, Since they are Mosfet powered?
And lastly, the Port sized recommended, Can that be altered? To a smaller Size. Reason being, the sound will change A lot of i change the port sizes. Seeing as how I'm not pushing the speakers, the tighter the enclosure the better they should sound.
I want to go with a 6" Round Port, With Baffles inside. I'd prefer the Sealed box, but i'm sure the manufacturer suggests against it for good reason. But I do know I won't be happy with that much port. the Speakers are going to sound like garbage. no really deep Bass in them, Or am I wrong?
Thanks again you guys are the best site so far Ive found for help. So Stick with what works!
btw where do i go to make donations? get this thing hooked up and I'll see what i can float over.
Thanks guys,
-PPI
MrBrownstone on 06/19/2006 12:46:34
Junkie
Now that we have a decision on the speakers, we have something to work with.
Concerning the box recommendations, these woofers are not designed to sound 'tight' or even care about the quality of sound. Although it is a stereotype of mine, if you see monstrous magnets, huge surrounds, and massive power ratings, plan on it being an SPL only woofer. Sounding like ass is not a problem when you are only playing 1 note. :-) In the 'daily' version of a vented enclosure, they'll sound decent, but you need 1kW per woofer.
Now for the port tuning...you can change that, but you are not going to make it sound 'better'. All you are going to do is change the frequency that the port is centered. I would recommend the 3.0cube 'everyday' box for your application. Sealed would sound like ass (not kidding) and the 'ultra' would sound quite 1-noted.
Coils? they are 2ohm coils. Are you implying that you are going to run 1 sub per amplifier? if so, you need to make a 4ohm load out of those coils. The only way is to use BOTH speakers on 1 amplifier.
A quad 2ohm coil woofer can be: 8ohm (all in series), 2ohm (series/parallel), and 1/2 ohm (all in parallel). Therefore, you need to run both woofers off 1 amplifier (both woofers on 1 amp) or you need an amplifier that'll deliver all the power @ 1 ohm or 4 ohms.
Any other configuration will not give your woofers proper power, or, you'll fry the amplifier.
I just bought 4 Audiobahn Immortal Awis12p's and I'm planning on powering them with an old 1996 PPI a1200 606.2
Now the old PPI i'm pretty familiar with... except for the old bridging connections. If i remember correctly, i can bridge the amp to 0 ohm stable, and run the speakers series. Only a few minor glitches in the whole scheme....
1) I cant remember which way to bridge the amp to 1 channel mono. -there is also aold rumor about PPI amps that you can juice them up to 18+ volts to increase the output. ( true/false?)
2) I haven't built the box yet - Need specs, audiobahn page doesn't allow access to specs, only lame advertisments.
Plan to use 1"mdf for the whole enclosure, the trunk allows for a 36"lenght x 26"wide x 14 1/2 tall (outside dimensions)
That's roughly 3.4 cf. for 4 speakers? (non ported box)
3) Surely don't know anything about the new quad coils, how to divide the oms per terminal, much less, how to even hook them up properly. Unless i only use one terminal, but where's the fun in that?
4) Is this PPI amp even strong enough to run all 4 of these?
If not what size amp(s) should i consider. Even tho that
PPI is selling for 800.00 on ebay right now. ( for good
reason That amp WAS a killer back in the day.)
Lastly, if at all possible, whats the best connections/box type -series / parallel / both? Whats the best type Isoberic / ported / sealed / bandpass?
** My Goal on the amp is to run the gains at 80%, that should power all 4 speakers somewhere between 500-600rms each, i realize this is low, but it should produce cleaner bass IMO.
The head Unit - 2005 Alpine cda9835
The Rear Speakers are Audiobahn AS69V (4 on back deck)
- Powered by Punch 200aiv (crossover in head unit)
Door Speakers/satellites -JL Audio XR653-CSi
- Powered by PPI a600 (1995 model)
Any help would be greatly appreciated!
Thanks
PPIJunkie!
Replies (12)
PPIJunkie on 06/14/2006 01:13:56
http://www.audiobahn.com/Audiobahn06/images/tech/2005.html
closest page I can find for Box Specs
ttocs on 06/14/2006 03:46:07
"Now the old PPI i'm pretty familiar with... except for the old bridging connections. If i remember correctly, i can bridge the amp to 0 ohm stable, and run the speakers series. Only a few minor glitches in the whole scheme.... "
all amps are stable at zero ohms...... with 0 watts output....
newB on 06/14/2006 04:14:46
yeah that caught my attention when i saw it... isnt that a short?
-Drew
PPIJunkie on 06/14/2006 10:14:12
Kinda the point. not too sure how to wire this thing together. I'd really prefer not to start a fire in the wigwam if ya know what i mean.
any help would be greatly appreciated.
swez on 06/14/2006 10:18:27
We need to get a manual for these PPI amps. Best thing to do, is contact PPI and ask for the install manuals for both amps. Once you have these, we can help you figure out what to do next.
To go further w/o the manuals is pure guess work and we don't want to see you wind up damaging your amps. These amps were built very well, but no amplifier can handle a ZERO ohm load. (Dead short to outputs)
One ohm, 1/2 ohm stable amps are possible with High Current topology amps. However, if these amps are not HC amps, they cannot take ultra-low ohmic loads w/o damage.
http://www.precisionpower.com/contact/default.asp
Swez
MrBrownstone on 06/14/2006 13:36:30
PPI Junkie
Sounds like you are coming out of retirement with those amplifers !!! :-) I haven't heard the A1200 or A600 in years.
Concerning how you operate your equipment, we may want to break it down in sections. Speakers, power, enclosure.
In the case of your woofers, there's no way in hell those woofers are designed to perform in a sealed enclosure. Also, they'll need 1000W each to operate effectively. And lastly, they are SPL woofers...are you at all concerned about the sound quality? if not, they're perfect! GRIN
Concerning amplifiers, there's only one type of amplifier that can efficiently supply power to those woofers, and that's a Class D. You need 1kW per sub, period. Otherwise, you'll be disappointed.
The box...well, are you ready to give up 1.5cuft per woofer? after displacement?
From there, we'll determine if you can even use these subs or amps in this configuration
MrBrownstone on 06/14/2006 13:39:28
PS I have a master's degree in Art series amplifiers...:-) You have 300Wx2 or 1200Wx1 @ 4 ohms.
You can run them 600Wx2 @ 2 ohms...but expect the heat to be something similar to a barbeque grill if the load is any lower. That amplifier is really best used @ 4 ohms mono on woofers.
They were great products for their time, and probably the best ABs running for 6 or 7 years...but a lot has changed.
PPIJunkie on 06/14/2006 21:33:09
Sounds like you are coming out of retirement with those amplifers !!! :-) I haven't heard the A1200 or A600 in years.
- Yes retirement is now an issue of the past....
- my brother talked me into putting a system back in the jalope.
Concerning how you operate your equipment, we may want to break it down in sections. Speakers, power, enclosure.
-speakers are 2/4 AWIS12P AudioBahn 12's. (Immortal Series)
Power, Awesome Question. Not too sure if what i have is enough
1996 ax606.2 and a 1995 a1200. Those are the 2 Amps I Intend on using. Whether it be one or both.
In the case of your woofers, there's no way in hell those woofers are designed to perform in a sealed enclosure. Also, they'll need 1000W each to operate effectively. And lastly, they are SPL woofers...are you at all concerned about the sound quality? if not, they're perfect!
-Sealed Enclosure? Thats all i know about! Ports? WTF are those.. lol kidding, the specs call for a 4x11 port. How I will break that up i'm not too sure yet.
3 options:
1) can do 1 port @4x11
2) can do 2 Ports @ 4.5x4.5 (divided chambers) (increase resistance to 5% or so. compaired to 20% at 4x11)
-site claims it helps.. true/false I'm not sure.
3) Run them Free Air, If that's EVEN POSSIBLE! ( thats the best SQ install IMO. These boxes don't cut it for me. Bass is too Pingy, and tight. like Looser Lower bass but yet powerful.
SPL Speakers? Seriously just not hip on the terminology.
My extent of installs is hiding wires, putting in head units, amps blah blah... and some intermediate wiring. Bridging, running series, parallel, isoberic,or just + to + and - to -.... Push Play.
I still don't know how to break the ohms down, or what is better.
To answer the question, sound quality is somewhat important. I have all my High's and Mids set perfect. Every beat/clash/is SUPERBLY Crisp. I would hate to ruin that by some lame sounding subs. It would be more important to me to have lower end subs with better quality, than to have 5 million watts in the trunk.
Concerning amplifiers, there's only one type of amplifier that can efficiently supply power to those woofers, and that's a Class D. You need 1kW per sub, period. Otherwise, you'll be disappointed.
Again not too sure on what my PPI amps are, Class D? RMS/peak, Can I bridge it to 2 Ohm mono? Can I Over Power them ( did that already 18v to each amp. ran a lil warm but otherwise no worse for the wear.) I thought they were. But, again my lack of knowlege in the dept makes me a little uncertain.
The box...well, are you ready to give up 1.5cuft per woofer? after displacement?
yeah what ever I have to lose to get these in the trunk is fine w/me I haven't opened the trunk since i put the 6x9's on the deck.
My basic problem is
1) is it sufficient power
2) how the sam hell do i wire these new types of speakers with multiple voice coils. And with the amps, Even if i bridge them to 2ohm 1 channel, how would i run them series or parallel?
3) The Box, the raw truth about limiting the port sizes to alot for breathing, can it be reduced by a %, to change the performance of the speakers?. the basic hook up is simple (power to amp)
Prob lies withing the Amp to the speakers. ( mainly the speakers). 2 sets of terminals and no clue what to do with them.
Do I run 2 amps to one speaker?
or do i run one anp to each speaker?
or the 2000 RMS means I can run 4 500/1 mono blocks to each one? this is the confusion i face.
I appreciate all the responces greatly.
I have contacted PPI and ordered the manuals today. be here friday.
- PPI Junkie
MrBrownstone on 06/14/2006 22:39:12
Why don't we look at just one thing at a time...the woofers.
Although the salesman (or Audiobahn) may have told you otherwise, these woofers are designed to reach maximum loudness...and waste a lot of power in the process. Although we can help you, plan on buying a different amplifier for best results. However, as we are making due with what we have....
Box
These woofers are made for a vented (ported) enclosure. Because of their stiff suspension, the 1st 25-50W or so are basically going to be wasted overcoming the suspension. Until you get to about 100W, you aren't going to hear the entire audio spectrum...and likely 200W.
Audiobahn recommends VENTED:
Everyday Driver
3.0 cu ft gross (2.3 net)
2-4" ports 15" long
Ultimate SPL
4.0cu ft gross (3.4 net)
2-4" ports 10" long
Essentially, the amount of space you were going to alot for all 4 woofers is what you need for EACH woofer?
Honestly, can you return 2 of them? or do you have 10-12cuft for this design?
swez on 06/16/2006 13:03:33
Frankly, many of us here know the value of less is more. Having 4 subs of this design, requires a very large enclosure, a huge amount of power to run the amps to rated potential and major electrical upgrades to go with the package.
If you are planning to compete it SPL Comps, then consider this a long term project with much $$$$ to be invested. However, if you wish to enjoy strong bass and skip all the added work, expense and loss of space, 1-2 of these subs are more than adequate.
Say more on which way you wish to go.
Swez
PPIJunkie on 06/19/2006 12:13:02
I have made the decision that I'll only use 2 of the 12's. And the 2 PPI amps. Balancing the power from the amps shouldnt be too hard tho, if i seperate the compartments for each speaker. yes/no?
ax606.2 and a A1200. Same thing except the Ax606 has a Xover in it.
the Amps and the wiring are the hard part. These have quad coils. So i'm wondering how the connections are.
1) got the specs on the amp to bridge them both down to 1 channel each. so each speaker will get roughly 1200 w RMS.So i'm hoping i should be able to turn the gains to 75%-80% and utilize the power of the amps as best as possible. without distorting too much.
2) the series/parrallel. which one or both?
Speakers can go to .( ?? Im guessing any ) ohm. but the amp is bottomed out at 4ohm mono. anything lower than 11 volts, or 4 ohms will trigger the the protect circuit.
Amp Stats are.
power Bandwith 10Hz - 50kHz
THD 0.02%
Input Sensitivity .2- 2.5 v ( my H/U has 5 V PreAmp out... that a problem?
Input Imperdance (stereo) 2-8 ohms
Load impeadance (bridged) 4-8 Ohms.
Supply Voltage 11-18v
Then there is the wiring. I know the amp wiring, but the speakers..... Whats the best way, JLaudio.com has a chart that gives the Diagrams for changing ohms, and wiring choices. But which is the best way for these amps, Since they are Mosfet powered?
And lastly, the Port sized recommended, Can that be altered? To a smaller Size. Reason being, the sound will change A lot of i change the port sizes. Seeing as how I'm not pushing the speakers, the tighter the enclosure the better they should sound.
I want to go with a 6" Round Port, With Baffles inside. I'd prefer the Sealed box, but i'm sure the manufacturer suggests against it for good reason. But I do know I won't be happy with that much port. the Speakers are going to sound like garbage. no really deep Bass in them, Or am I wrong?
Thanks again you guys are the best site so far Ive found for help. So Stick with what works!
btw where do i go to make donations? get this thing hooked up and I'll see what i can float over.
Thanks guys,
-PPI
MrBrownstone on 06/19/2006 12:46:34
Junkie
Now that we have a decision on the speakers, we have something to work with.
Concerning the box recommendations, these woofers are not designed to sound 'tight' or even care about the quality of sound. Although it is a stereotype of mine, if you see monstrous magnets, huge surrounds, and massive power ratings, plan on it being an SPL only woofer. Sounding like ass is not a problem when you are only playing 1 note. :-) In the 'daily' version of a vented enclosure, they'll sound decent, but you need 1kW per woofer.
Now for the port tuning...you can change that, but you are not going to make it sound 'better'. All you are going to do is change the frequency that the port is centered. I would recommend the 3.0cube 'everyday' box for your application. Sealed would sound like ass (not kidding) and the 'ultra' would sound quite 1-noted.
Coils? they are 2ohm coils. Are you implying that you are going to run 1 sub per amplifier? if so, you need to make a 4ohm load out of those coils. The only way is to use BOTH speakers on 1 amplifier.
A quad 2ohm coil woofer can be: 8ohm (all in series), 2ohm (series/parallel), and 1/2 ohm (all in parallel). Therefore, you need to run both woofers off 1 amplifier (both woofers on 1 amp) or you need an amplifier that'll deliver all the power @ 1 ohm or 4 ohms.
Any other configuration will not give your woofers proper power, or, you'll fry the amplifier.
Copyright ClubKnowledge 2009 * All Rights Reserved
