to bridge them or not

[00camaro16]

ok i have a pioneer 760w amp and two 500w jl subs. the amp has 2 channels but can be bridged. it says something about 125w x 2/4 ohms or 380w x 1/4 ohm. should i bridge them or not. i want to supply my subs with the 380w. im sorry i don't know stereo systems. help me please.

[LSCyaL8R]

Sounds like you need more amplification.... if you have 2 500 watt JL subs and want to give them the most power then you need a two channel amp that can provide 500watts RMS to each channel.

Bridging your pioneer will let you give 380w to ONE of those subs.... not both. so you are stuck with 125w to each sub.

I don't know which JL you have so i'm not sure if your 500w rating is MAX or RMS. if it's RMS you have a LOT of room to get bigger and better amps in there.

[pajeff02]

It's been a while since my car audio days -- my recollection is that if you "bridge the amp" you end up with one channel. Since you have two (2) subs, the only way you would be able to run one (1) channel and power both subs is if you run them in series or parallel. Both affect the impedance seen by the amplifier. Running them in series doubles the impedance and running them in parallel halves the impedance. Therefore, it depends upon your speakers impedance (rated in ohms) and the amp's rating.

__________________________________________

Edit: I don't type fast enough.

[LSCyaL8R]

actually pajeff... you are right. but this also depends on the impedance of the subs. does he have 1 ohm subs? 2.... 4.... also... are the subs single voice coil? dual voice coil? JL makes some quality full featured units so more info is needed to make an informed reccomendation


Edit:

for example. To run 2 subs bridged on a 4 ohm stable amp you need to have 2 SVC 8 ohm subs. likewise if you have 4 ohm subs then you can wire them to present a 2 ohm load to the amp.

[pajeff02]

It's been a while since my car audio days -- my recollection is that if you "bridge the amp" you end up with one channel. Since you have two (2) subs, the only way you would be able to run one (1) channel and power both subs is if you run them in series or parallel. Both affect the impedance seen by the amplifier. Running them in series doubles the impedance and running them in parallel halves the impedance. Therefore, it depends upon your speakers impedance (rated in ohms) and the amp's rating.

__________________________________________

Edit: I don't type fast enough.

actually pajeff... you are right. but this also depends on the impedance of the subs. does he have 1 ohm subs? 2.... 4.... also... are the subs single voice coil? dual voice coil? JL makes some quality full featured units so more info is needed to make an informed reccomendation


Edit:

for example. To run 2 subs bridged on a 4 ohm stable amp you need to have 2 SVC 8 ohm subs. likewise if you have 4 ohm subs then you can wire them to present a 2 ohm load to the amp.

We are on the same page.

[00camaro16]

they are w3v3 in 10 inch, which are single voice. the amp i have is a pioneer 2 channel. so what im hearing is to not bridge them, to use it as a 2 channel.

[stew215]

Anyway you wire them together it will work ... but in the long run you WILL blow your amp. Your subs are trying to draw 500 watts RMS from an amp that can only put out 380 RMS. This means that the amp will most likely overheat and put it into protect mode or just fry the transistors.

Heat + Electronics =

[stew215]

Also like stated before if your amp is not 2 ohm stable you will have to run it as a dual channel and not bridge them. That would give you 125 watts RMS to each sub.....

[00camaro16]

Also like stated before if your amp is not 2 ohm stable you will have to run it as a dual channel and not bridge them. That would give you 125 watts RMS to each sub.....

so why do they even advertise it as 760w amp if it can never reach that out put no matter how you wire it. shouldn't you say it a 380w since thats the max it can send.

[02WS6dream]

Anyway you wire them together it will work ... but in the long run you WILL blow your amp. Your subs are trying to draw 500 watts RMS from an amp that can only put out 380 RMS. This means that the amp will most likely overheat and put it into protect mode or just fry the transistors.

Heat + Electronics =

inaccurate. I follow your logic--but understand that a speaker's wattage rating is not the same as 'trying to draw'. they aren't 'trying to draw' anything--the rms and max wattage ratings on the subs represent the amount of power the voice coils can safely handle without overheating and burnin up. as stated before--its depends on the rating of the amp. many modern amps are two ohm stable--if yours is i would recommend bridging it to the subs wired in parallel--presenting a 2 ohm load the amp and extracting maximum safe power from it. If the amp must see 4 ohms, you're best with one sub/channel for max safe power. overworking the amp (too low impedence or over volume causing it to clip/distort) is what commonly leads to speaker/component failure. the JL site actually has great wiring diagrams/explanations if you're curious to learn more.

[pajeff02]

Agree. The speakers do not "draw" anything -- whatever wattage you send them they will accept. Too little and the speakers will not perform as well, too much and they will blow, and impedances have to be considered.

Max (or peak) and RMS wattage are two entirely different things. A lot of the cheaper speaker brands boast max or peak wattage. This is what they will be able to handle for but an instant. RMS is what they can handle all day long -- this is the rating that really matters and what all good speakers are truly measured by.

[stew215]

inaccurate. I follow your logic--but understand that a speaker's wattage rating is not the same as 'trying to draw'. they aren't 'trying to draw' anything--the rms and max wattage ratings on the subs represent the amount of power the voice coils can safely handle without overheating and burnin up. as stated before--its depends on the rating of the amp. many modern amps are two ohm stable--if yours is i would recommend bridging it to the subs wired in parallel--presenting a 2 ohm load the amp and extracting maximum safe power from it. If the amp must see 4 ohms, you're best with one sub/channel for max safe power. overworking the amp (too low impedence or over volume causing it to clip/distort) is what commonly leads to speaker/component failure. the JL site actually has great wiring diagrams/explanations if you're curious to learn more.

Yeah i was not really all there when i wrote that ( last few minutes of work! ) ...Good catch ... I was trying to write that the sub can handle 500 watts and the amp can only put out 380..With the amp only supplying a percentage of the the subs max power you will have to turn the sub volume higher then if you would have had to with an amp supplying over 500 watts.Thus causing the amp to get hotter.

I have seen it a few times that people from school bought amps that could not deliver full power to there subs. Because the sound was so low, they cranked the amp up to full power the whole time they drove. Within a week they blew there amp from over heating. Not sure if this will happen with all setups but it did happen to more then one person.

[stew215]

so why do they even advertise it as 760w amp if it can never reach that out put no matter how you wire it. shouldn't you say it a 380w since thats the max it can send.

They advertise them at Max rating so people will buy them. If some kid went into walmart and was looking at too amps the same price, one said 380w and the other said 760w.....what do you think there choice would be?


Does anyone know how to calculate the max value ? It just seems to be a magical number the companys come up with

[00camaro16]

so if i wanted to supply both of my subs with 380w(what jl recommends) of continuous power at the same time. what are the specification of the amp i should buy. this is all really confusing for me i still don't quite get it.

[pajeff02]

so if i wanted to supply both of my subs with 380w(what jl recommends) of continuous power at the same time. what are the specification of the amp i should buy. this is all really confusing for me i still don't quite get it.

IMO - wire the subs up, one to each channel, and let it rip. You might be surprised at the result. Don't worry about JL's 380 watt crap. Does your amp have a low pass filter?

[00camaro16]

IMO - wire the subs up, one to each channel, and let it rip. You might be surprised at the result. Don't worry about JL's 380 watt crap. Does your amp have a low pass filter?

yes, preset at 40hz i believe and its on

[bberretta]

2 questions:

1. What ohm rating are your subs? (2,4, or 8)
2. Which amp do you have? This way we can determine how far you can push the amp. For example- if your subs are 8 ohm and your amp is stable enough to handle it, you could bridge it to a 4ohm mono and get more power out of it than if you just wire it left/right. If they are 2ohm subs, then bridging them could drop it to 1ohm and burn your amp up if it can't handle it. Most likely, they are 4 ohm, bridged to 2ohm. If your amp is a Pioneer 5100T, they do not recommend bridging it if the subs are less than 8ohm.

[00camaro16]

2 questions:

1. What ohm rating are your subs? (2,4, or 8)
2. Which amp do you have? This way we can determine how far you can push the amp. For example- if your subs are 8 ohm and your amp is stable enough to handle it, you could bridge it to a 4ohm mono and get more power out of it than if you just wire it left/right. If they are 2ohm subs, then bridging them could drop it to 1ohm and burn your amp up if it can't handle it. Most likely, they are 4 ohm, bridged to 2ohm. If your amp is a Pioneer 5100T, they do not recommend bridging it if the subs are less than 8ohm.

yea it a 5100t and the subs are 10 inch jl w3's. so bridging them is not the right option then. right now i have them wired 1 per channel, which has always worked i was just wondering if i could get more power out of them with the same amp. im a college student so i have no money (zero) to spend on a new amp.