Component question (passive and bi-amp)

[kevin lu 10+ year member]

I have a set of comp that give me 2 option to run passive or bi-amp, i understand that bi-amp can play louder but do they sound better in sound quality?

Thanks

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[keep_hope_alive Premium Member]

bi-amp gives you the opportunity to give more power to the midbass, allows for better level adjustment, and even time alignment - all active.

you need four amp channels to run the component set with bi-amp. you can't necessarily play louder bi-amp unless you give the speakers more power than you do passive.

example: if you have a 50Wx4 amp you can bi-amp the fronts at 50W per speaker, or you can bridge the amp at 200Wx2 and run passive. in this case the latter will be louder due to more power.

 

[fasfocus00 5,000+ posts]

if you only have a 2 channel amp that's 2 ohms stable you can run it that way too.

 

[keep_hope_alive Premium Member]

if you only have a 2 channel amp that's 2 ohms stable you can run it that way too.

false. if you only have a two channel amp for both left and right speakers - it's not bi-amp. the term bi-amp implies you have two amp channels for each crossover - one amp channel for each tweeter and one amp channel for each woofer.. the jumpers at the crossover just feed the woofer and tweeter from the same input. it doesn't matter if they combine at the crossover or if they combine at the amp. it's similar to running active, but you're using the passive crossovers because you either don't have enough crossovers on the amp or because you like the way the speakers sound with the crossovers.

nor do you need to be 2 ohm stable. remember that the amp only sees one speaker at a time due to the crossover. below the crossover point it only sees the woofer. above the crossover point it only sees the tweeter. if each are 4 ohms, then the load is 4 ohms.

bi-amp is only useful if you have some processing you want to apply separately in or before the 4 amp channels. IMO - you need to have extra amp channels burning a hole in your pocket to make it worthwhile. you also need to have enough power to begin with. don't bi-amp and reduce power output (unless you're doing T/A).

usually when you bi-amp, you're giving the speakers 1/4 the power you could if you just bridged and ran them normally.

 

[kevin lu 10+ year member]

My Arc amp is 90.4 at 4ohms, 175.4 at 2ohms.

My component (KRX2) is rate at 100rms 2 ohms speaker so what the best option to run them?

Do they sound better if i bi-amp them?

Thanks K H A

 

[keep_hope_alive Premium Member]

hmmm, with that amp, bridging is probably out of the question unless it's 2 ohm bridged stable.

you have 2 ohm tweeters? regardless, that's plenty of power to consider bi-amp. go for it. i don't think you'll gain any output or SQ - just the ability to control the tweeter level separate from the woofer level, maybe increase crossover slopes, and add separate processing if you have that capability.

 

[kevin lu 10+ year member]

hmmm, with that amp, bridging is probably out of the question unless it's 2 ohm bridged stable.
you have 2 ohm tweeters? regardless, that's plenty of power to consider bi-amp. go for it. i don't think you'll gain any output or SQ - just the ability to control the tweeter level separate from the woofer level, maybe increase crossover slopes, and add separate processing if you have that capability.

Sorry they are 350.2 at 2ohms

The KRX2 is 2 ohms comp.

 

[fasfocus00 5,000+ posts]

false. if you only have a two channel amp for both left and right speakers - it's not bi-amp. the term bi-amp implies you have two amp channels for each crossover - one amp channel for each tweeter and one amp channel for each woofer.. the jumpers at the crossover just feed the woofer and tweeter from the same input. it doesn't matter if they combine at the crossover or if they combine at the amp. it's similar to running active, but you're using the passive crossovers because you either don't have enough crossovers on the amp or because you like the way the speakers sound with the crossovers.
nor do you need to be 2 ohm stable. remember that the amp only sees one speaker at a time due to the crossover. below the crossover point it only sees the woofer. above the crossover point it only sees the tweeter. if each are 4 ohms, then the load is 4 ohms.

bi-amp is only useful if you have some processing you want to apply separately in or before the 4 amp channels. IMO - you need to have extra amp channels burning a hole in your pocket to make it worthwhile. you also need to have enough power to begin with. don't bi-amp and reduce power output (unless you're doing T/A).

usually when you bi-amp, you're giving the speakers 1/4 the power you could if you just bridged and ran them normally.

wow, really. have you even owned a set of bi-ampable components? I've ran bi-amplable MB Quarts for over 12 years. bi-amp is just the passive crossover network allowing 2 (hence the word "bi") inputs, allowing one input to go to the tweeter and one going to the midrange. the crossover frequencies are still the same no matter which way you do it. the first bi-amp crossover were meant to give you the user the tuning capabilites of active setup with out the price of an active crossover. you are also sadly mistaken in you stating that the amp only sees 4 ohms due to the crossover. if you bi amp the crossover, it'll see independent loads of 4 ohms, so if each is on the same channel it'll see 2 4 ohm loads resulting in a 2 ohm load. so if he has a 2 channel amp that put out 50x2@4ohms and 75x2@2ohms, if he runs his crossover in the bi-amp setting the amp will see a 2 ohm load resulting in more power being sent to the speakers. bi-amping is not only useful if you have separate processing, it is useful in being able to run at a lower impedance to get more power from your amp.

 

[ciaonzo 5,000+ posts]

The sole purpose of bi-amplification is to escape amplifier clipping caused by high amplitude high frequency information riding on top of high amplitude low frequency information, as seen in the first graph. You move to four channels of amplification but you retain the passive network, and it's a step beneath going completely active. You will enjoy lowered distortion and prolonged tweeter life. Bi-amplification provides the results you see in the second group of graphs.

 

[skittlesRgood 10+ year member]

im guessing he isnt running and processors so to answer his question. it shouldnt sound any better or worse. it will allow you to turn up and down the tweeter and mid levels to blend them a little better. they should get louder as well.

ciaonzo - the amp will still get the same signal as the 1st pic because its still getting the same input. so each of the 4 channels will get the full range, like in pic 1, then change to the other pics after the crossover. the only way to change the signal at the amp is going active.

 

[kevin lu 10+ year member]

I have a Arc XEQ and 2 Arc amps, my system sound very good but i just want to learn more about car audio and get the best out of it.

Thanks.

 

[supermaxx123 10+ year member]

bi-amp gives you the opportunity to give more power to the midbass, allows for better level adjustment, and even time alignment - all active.
you need four amp channels to run the component set with bi-amp. you can't necessarily play louder bi-amp unless you give the speakers more power than you do passive.

example: if you have a 50Wx4 amp you can bi-amp the fronts at 50W per speaker, or you can bridge the amp at 200Wx2 and run passive. in this case the latter will be louder due to more power.

what are you smoking? how can your be running active running a passive crossover?

 

[keep_hope_alive Premium Member]

what are you smoking? how can your be running active running a passive crossover?

that's not a proper sentence. you're obviously the one smoking something. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

bi-amp is one step away from full active. you can even be running "active" - i.e. one amp channel per speaker with active crossovers and still use a passive crossover. you can insert the bi-amp capable passive crossover to allow for more adjustments - as plenty of other shave suggested. based on the graphs above from ciaonzo, the ONLY way you'd have any benefit from bi-amp is if you used active crossovers BEFORE the passive crossover to clean up the signal and separate frequencies. Granted, i disagree with the presentation of his information and reasoning behind it, but i know what he's trying to say.

example: alpine type-x pro crossovers have jumpers that allow you to tune the crossover settings, crossover points, slopes, tweeter level, etc. things that may not be easy for someone based on amplifier selection/location. you also retain tweeter protection circuits by using the passive crossover. and the type-x crossovers have settings that allow adjustment based on speaker location and aiming. without a decent processor, these features may be attractive to someone.

some passive crossover networks are designed to actually improve the sound quality of the speaker system - by addressing known response issues. granted, in the sub $500 category passive crossovers are usually just filters.

the main reason for bi-amp is to give more power to your midbass/woofer than to the tweeter.

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