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[ejschultz 10+ year member]

Okay. I've got a question that may seem irrelevant or possibly plain stupid. This question stems from the bi-wiring theory. The point of bi-wiring is to get cleaner signal to a crossover that supports bi-wiring by having speaker wire only carry the frequencies it will pass to specific drivers. I'm taking this from PPI crossovers that are designed to be bi-wired. Suppose that if I were to go active and keep the exact same crossover points that are given with the passive crossovers, the RCAs going to my amp will only carry the given frequencies for a specific driver, the amplifier will only amplify given frequencies for a given driver, and the speaker wire will only carry an amplified signal of the specific frequencies for the given driver they will be powering. Essentially everything should be "cleaner" because everything will be processed after the head unit only in certain frequencies instead of every channel processing every frequency up to the passive crossover. Am I correct in this assumption?

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[HCCA 10+ year member]

I understand that you are wanting to know the benefits of bi-wiring. However, the more you wrote about your question, the less I understood what you want to know, specifically.

In my book...If you bi-wire (from what I've seen guys want to do) you are simply using a seperate amp channel to feed the tweeter, and another channel to feed the mid; while still using the supplied passives. Does it improve the SQ??? I've never heard a difference. In fact, I've heard system that won SQ contests that were ALL passive off of the SAME AMP!!!

 

[ejschultz 10+ year member]

I understand that you are wanting to know the benefits of bi-wiring. However, the more you wrote about your question, the less I understood what you want to know, specifically.
In my book...If you bi-wire (from what I've seen guys want to do) you are simply using a seperate amp channel to feed the tweeter, and another channel to feed the mid; while still using the supplied passives. Does it improve the SQ??? I've never heard a difference. In fact, I've heard system that won SQ contests that were ALL passive off of the SAME AMP!!!

I guess that doesn't really surprise me. There are a lot of high grade passive crossovers available assuming one has the money to purchase them. When using different channels of the amp to power a passive crossover, you're bi-amping, not bi-wiring. Bi-wiring uses the same channel of an amp but has 2 runs of speaker wire going to a passive crossover that has a mid and tweeter input. Here's a link on bi-wiring.

http://www.brilliancehifi.co.uk/how-to-bi-wire-speakers.htm

Basically I'm taking this one step further by doing all the processing within my HU. The RCAs, amp channels, and speaker wire will all carry the frequencies for the mids or the tweeters. None of which will carry a full range signal.

 

[FJF 10+ year member]

Bi-wiring uses the same channel of an amp but has 2 runs of speaker wire going to a passive crossover that has a mid and tweeter input. Here's a link on bi-wiring.

Bi-wiring is a debated topic in High-End. Personally, having auditioned the concept (many,many times) with some of the highest resolution gear available, I never heard a difference. Other folks feel differently.

 

[ejschultz 10+ year member]

Bi-wiring is a debated topic in High-End. Personally, having auditioned the concept (many,many times) with some of the highest resolution gear available, I never heard a difference. Other folks feel differently.

Now, I've never personally heard anything bi-wired so I don't have a good comparison. However, the theory behind it does make sense, but the amplifier is still processing a full range signal. Would the overall sound be cleaner if the amp channels and the RCAs going to the amp only carried certain frequencies instead of a full range signal?

 

[FJF 10+ year member]

Would the overall sound be cleaner if the amp channels and the RCAs going to the amp only carried certain frequencies instead of a full range signal?

Yes, under optimal circumstances. With a car system of this type, there may not be much of a change. Only one way to find out. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

This said, looking at the things as they sit, I think you're making the right decision by using the deck's processing instead of the amps' x-overs. That, alone, can account for the sonic difference you may hear.

 

[ejschultz 10+ year member]

Yes, under optimal circumstances. With a car system of this type, there may not be much of a change. Only one way to find out. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif
This said, looking at the things as they sit, I think you're making the right decision by using the deck's processing instead of the amps' x-overs. That, alone, can account for the sonic difference you may hear.

I'm not using my amp's crossovers; I'm using the passive crossovers that came with my 720PRS components. They seem to be a rather well built crossover. My one "gripe", if one would even call it that, is that I'll be losing power going to my front stage if I run my speakers active. In their current configuration, my fronts pull 200 watts RMS x 2. My amp is rated at 70x4 at 4 ohms. The mids are less than 4 ohms; I cannot remember the exact impedance. The tweeters are 5 ohm tweeters. I don't care if the tweeter pulls less power because I'd assume there's protection in the crossover for them that absorbs some of the power anyways. I know I'll be losing out on midbass power, but I don't know exactly how much. I guess I'll just have to try it and see...

 

[ejschultz 10+ year member]

Any other input on my inquiry?

 

[ejschultz 10+ year member]

Going back to my second to last post, I guess there's probably a little power loss within the passive crossover as well. I doubt it would be perfectly efficient. However, I don't believe that the power loss in the passive crossover would equal 200 watts RMS - loss

 

[FJF 10+ year member]

Going back to my second to last post, I guess there's probably a little power loss within the passive crossover as well. I doubt it would be perfectly efficient. However, I don't believe that the power loss in the passive crossover would equal 200 watts RMS - loss
I wouldn't even think about it, especially considering how many other pieces fit into the equation. It's just not a concern. Why is that, you may ask? I can only suggest that you look into the relationships at hand outside of car audio. Or, you could simply see how it sounds to your ears, as you mentioned.

 

[ejschultz 10+ year member]

I wouldn't even think about it, especially considering how many other pieces fit into the equation. It's just not a concern. Why is that, you may ask? I can only suggest that you look into the relationships at hand outside of car audio. Or, you could simply see how it sounds to your ears, as you mentioned.

I didn't think it should be a concern, it's just going to be something in the back of my mind as I'm tearing apart my car to run more speaker wire to the front. I guess I'll be going active just to try it out and see if I like it any better. Either way, active or not, I feel as though I'm wasting something. By using the passive crossovers, I might as well not be using an 800PRS. If I go active, I feel I'm wasting the crossovers that came with my 720PRS components. I'm ****ed if I do and ****ed if I don't. I'm still assuming though that active will sound cleaner because of my "theory", if one could call it that.