Has anyone had madisound custom build you crossovers?

[Mackenzie]

I am looking at completely redoing my front stage this time around. Im wanting to run a very efficient, but still decent sq. Im not looking to run an active system. Im thinking about just picking out drivers, and have madisound make the crossovers for them. Its really not expensive at all, and I should be able to come out with a killer set for under 200. Obviously I would make sure the drivers work well with each other first, but I thought this may be a good solution to a better front stage, and an efficient one, without a horn install. They seem to cater to car audio quite a bit actually, as they aready have some kits available.

Thoughts? Has anyone tried their custom designs?

[Eric D]

I for one am impressed to hear you want to try something more "from scratch", as no one ever seems to do this, and it is indeed challenging.

My best advice for you is to setup a temporary system using active crossovers, and multiple amplifiers. Even if you have to borrow the equipment. Try some logical crossover values first, and then tweak the tuning until you get the best sound you are happy with. Once known, make note of these crossover values, and have Madisound build your passive crossover to mimic your findings from the temporary test setup.

You may still wish to adjust values a bit, but even cheap crossover parts at not really all that cheap (IMO), so you probably don't want to buy a bunch of parts you will likely not use.

[dwnrodeo]

I too have played around with having Madisound build custom crossovers for Seas speakers. If you want specific drivers that don't have crossovers intended for them, having Madisound design and build your crossovers makes sense. A lot of thought and knowledge goes into the design of a passive crossover and even a bit of trial and error, which can get expensive if you start buying components and trying different values. I for one enjoy browsing this site: http://www.troelsgravesen.dk/Diy_Loudsp ... structions There is a lot of knowledge on speaker construction and quite a few examples that can help you with crossover design.

[ttocs]

if you are wanting efficient then you do not want to run passive crossovers as they suck up more energy then you would think, and probably want. Why not go with an active electronic crossover as it will allow you to tune your system and make it sound the way you want it too? Passives are a one time shot and you hope you will get it right. I would assume that most brands would do listening tests to see which sounded best and why while trying out a few different types, you will not have that luxury and will have to hope you matched it correctly.

[dwnrodeo]

if you are wanting efficient then you do not want to run passive crossovers as they suck up more energy then you would think, and probably want. Why not go with an active electronic crossover as it will allow you to tune your system and make it sound the way you want it too? Passives are a one time shot and you hope you will get it right. I would assume that most brands would do listening tests to see which sounded best and why while trying out a few different types, you will not have that luxury and will have to hope you matched it correctly.

Very true. The ONLY benefit of running passive is less amplifier channels required. The reason I want to run passive components on my next install is to minimize the number of amplifiers/channels and use one amp to run a 3-way setup.

[shawn k]

if you are wanting efficient then you do not want to run passive crossovers as they suck up more energy then you would think, and probably want. Why not go with an active electronic crossover as it will allow you to tune your system and make it sound the way you want it too? Passives are a one time shot and you hope you will get it right. I would assume that most brands would do listening tests to see which sounded best and why while trying out a few different types, you will not have that luxury and will have to hope you matched it correctly.

Very true. The ONLY benefit of running passive is less amplifier channels required. The reason I want to run passive components on my next install is to minimize the number of amplifiers/channels and use one amp to run a 3-way setup.

I agree with both of you here. Both are valid points! But Mackenzie stated he wanted "efficient" and running passive xovers is not an efficient solution..... just saying. I'm curious what kind of $$ you're looking at for the custom built xovers??

[Eric D]

Efficiency all depends on how you look at it.

Yes a passive crossover on a speaker is not as efficient as an active speaker without one, but the amount of energy used up by the passive crossover is pretty minimal. Ever feel how hot passive crossovers get when running them? They don't get hot at all, unless you are running them well beyond their ratings. Then they saturate and all hell breaks loose.

The other flip side to efficiency is you need more channels to run an active setup, so really is it less efficient by a long shot. 50W x 2 can run a set of components with a passive crossover, but if you want to go active you would need 50W x 4, or twice the amplifier as you had before. You could probably get by in my example here with only 25W x 2 on the tweeters, but that is still 75W a channel needed active, over only 50W a channel passive. So as far as amplifier power is concerned, running a passive setup is more efficient.

[shawn k]

Efficiency all depends on how you look at it.

Yes a passive crossover on a speaker is not as efficient as an active speaker without one, but the amount of energy used up by the passive crossover is pretty minimal. Ever feel how hot passive crossovers get when running them? They don't get hot at all, unless you are running them well beyond their ratings. Then they saturate and all hell breaks loose.

The other flip side to efficiency is you need more channels to run an active setup, so really is it less efficient by a long shot. 50W x 2 can run a set of components with a passive crossover, but if you want to go active you would need 50W x 4, or twice the amplifier as you had before. You could probably get by in my example here with only 25W x 2 on the tweeters, but that is still 75W a channel needed active, over only 50W a channel passive. So as far as amplifier power is concerned, running a passive setup is more efficient.

Ummm no man. Yeah, it's true that you will need more channels to run active but that's it. You state: " 50W x 2 can run a set of components with a passive crossover, but if you want to go active you would need 50W x 4, or twice the amplifier as you had before." but this is not true. You don't "need" to double your power just because you're running active! You can easily enough run four channels @ 25w each and have the same current damand from the charging system. The "efficiency" comes from removing the passive crossover. How ever much power you want to run is a whole different issue.

[holmis]

Efficiency all depends on how you look at it.

Yes a passive crossover on a speaker is not as efficient as an active speaker without one, but the amount of energy used up by the passive crossover is pretty minimal. Ever feel how hot passive crossovers get when running them? They don't get hot at all, unless you are running them well beyond their ratings. Then they saturate and all hell breaks loose.

The other flip side to efficiency is you need more channels to run an active setup, so really is it less efficient by a long shot. 50W x 2 can run a set of components with a passive crossover, but if you want to go active you would need 50W x 4, or twice the amplifier as you had before. You could probably get by in my example here with only 25W x 2 on the tweeters, but that is still 75W a channel needed active, over only 50W a channel passive. So as far as amplifier power is concerned, running a passive setup is more efficient.

Ummm no man. Yeah, it's true that you will need more channels to run active but that's it. You state: " 50W x 2 can run a set of components with a passive crossover, but if you want to go active you would need 50W x 4, or twice the amplifier as you had before." but this is not true. You don't "need" to double your power just because you're running active! You can easily enough run four channels @ 25w each and have the same current damand from the charging system. The "efficiency" comes from removing the passive crossover. How ever much power you want to run is a whole different issue.

That is not true either.... Amps has not a 100% eff. rate...
That means you loose more power when needing more amps/channels... not much, but som % it is..

[shawn k]

That is not true either.... Amps has not a 100% eff. rate...
That means you loose more power when needing more amps/channels... not much, but som % it is..

Yes my friend, it is true. It doesn't matter if it's a 25wx4 amp or 50wx2 amp. The efficiency is going to be nearly identical (for similarly designed/model amps). Approximately 50-60% for most class a/b amps and 70-90% for full bandwidth class d's.

[Eric D]

It is a very common misconception that amplifiers “push” power into a speaker. I read it all the time on eBay with comments like “this amp will really push your speakers”, or “pushes a lot more than rated at”.

All an amplifier does is provide a voltage at its outputs, and then the resistance (impedance) of the loudspeaker “draws” current from the amplifier. This is why a 2 ohm speaker will get twice the power of a 4 ohm. It has half the resistance, so it draws twice the current. Current multiplied by voltage is power. With the same voltage, and twice the current you get twice the power.

If you don’t connect a speaker to an amp, the amp won’t get all that hot at full output. You have some heat generated by the power supply section of the amp, and some generated by the Class A biasing of the Class A/B output section, plus some power ate up by the Class A preamp section as well. All in all, not much power though, so not much heat.

Now think about a midrange speaker. Say we connect it to an amplifier which has a tone of 100Hz as its output, and it is at 10V. If you use a DMM, you will measure 10V at the terminals to the speaker. (yes the wire has some resistance, but for this discussion it is negligible)

Take that same speaker, but now insert an inductor in series with one of its terminals. Use an inductor value for a crossover point of 5kHz. Again, play the 100Hz tone, at 10V, and you will measure 10V at the speaker terminals. All of your power is getting to the midrange, and you will find the inductor is not getting hot at all. Below the crossover point, the inductor is “acting as a wire”. It has little affect on anything. (Note: you will get less than 10V at the speaker due to some resistance of the inductor, but it might not even be something you can measure on a typical DMM, say 9.999V for example)

Now keep that setup as is, and play a 10kHz tone again at 10V. This time you will find you measure very little, or almost 0V at the speaker terminals. So, where is the signal going then? It must be getting ate up by the inductor (passive crossover). Wrong! The power never really leaves the amplifier. When you go above the crossover point with this inductor setup, it exponentially increases in impedance. It presents almost no load to the amplifier, and “blocks” the current from passing to the speaker. Go high enough in frequency and it is almost as if you disconnected the speaker altogether.

Capacitors work just the opposite of inductors. At high frequency they act as a short, and easily pass current. At low frequencies they act as an open, and will not allow current to pass.

Now, as with everything there are exceptions to the rule. If you use an inductor with too small a wire, it will heat up with higher power into it, and can even burn up in the right situation. Same for the capacitor. If you use a cap rated for only 10V, but then put 100V AC on it, it will probably heat up so quick it explodes.

Now, what about resistors? If you go back up to my first example and hook up the midrange with the inductor, and then in parallel with it you hook up a tweeter using a capacitor instead of the inductor, you would be making a two way, 1st order crossover system. There is a good chance you will have a tweeter in this system which is too loud. Tweeters tend to be quite efficient, so they don’t usually need as much power. So how do you make the tweeter quieter? Well, if you turn down the output of the amp, you end up making the midrange quieter as well, so you still end up with a tweeter which is too loud

The solution is to put a resistor in series with the tweeter. By doing this, some of the power goes to the tweeter, and some goes to the resistor. In this case the resistor is indeed a load, and is using up amplifier power. The power has to go somewhere, so it becomes heat. But, the benefit here is the tweeter is quieter, so it matches better with the midrange.

When you run an active setup, you have the ability to control the voltage to the tweeter and midrange independently, and with great accuracy. Since tweeters often need less than a midrange, you might find you only need an amplifier on your tweeters with half of the output of the amplifier on the midranges.

So, back to the passive crossover. The resistor in the passive crossover is indeed using up amplifier power, but it is not all that big of a deal, as you don’t want the tweeters so loud anyway, so the power being used up could not really be better utilized. One key disadvantage here is the power being used by the resistor has to come from your amplifier, so you are causing more heat in the amp, and depending on the situation this could be more distortion, or less control, or something else.

So, I guess my whole point with all this is passive crossovers don’t waste anything. The only energy they do waste is intentional, as a way to attenuate the output of a connected driver. Now, they are not without their problems though. They alter the phase of their connected speakers, and this can be an issue when not accounted for. They are also very challenging too design, so this to is a negative against them. Passive crossovers can also be expensive. Adding more amplifier channels for an active setup is always costly, but a very good passive crossover might cost more than a typical amplifier would! It all depends on the quality, size, and quantity of components in the crossover.

[Eric D]

Consider these three setup possibilities...

System A has a single 50W x 2 amplifier running a pair of components using their included passive crossovers.

System B has a the same exact 50W x 2 amplifier running on the midranges from the previous system, and another 25W x 2 (same brand and line) amplifier running on the tweeters from the previous system, with an active crossover being used.

System C has a pair of the 25W x 2 amplifiers from System B running the midranges and tweeters in an active setup like System B.

Here is what you will find...

System C will not be nearly as loud as the previous systems. It might still sound good, but if the owner had a chance to compare it to System A or System B, they would not be all that happy with their investment.

System A and System B will be just as loud as each other, as perceived by the human ear. There is potential for System B to be louder when measured by a precision SPL meter, but there is also potential for System A to actually be louder. In rare instances the combination of the loudspeaker drivers and the passive crossover network can actually lower impedance, thus drawing more current. Don’t quote me on this, but I think the term would be the system is acting in “resonance”.

Since System B is likely no louder than System A, I fail to see how System B could ever be more efficient. The addition of a second amplifier (no matter what the power), is still introducing more power into the system to get the same result.

Now, there is indeed potential for System B to sound better than System A. But, this is going to be so depended on personal opinion, I see no way to ever prove anything. Just as system B could sound better than A, the inverse could be true as well. It would depend on just how well the active setup turned out, or how well the passive setup was designed. One could easily sound better than the other.

[shawn k]

For the most part............. ABSOFRIGNLUTELY!

And for these reasons, that's why I asked how much $$ the passives will run him. In order to design and build a passive with very minimal loss, one is typically looking at HUGE $$$. Hell, just a 6db two way low loss crossover can run $100+ And that's only 6db!!!!!!! And as TTOCS had previously touched on, you're now completely "stuck" with the xover point. Now even "if" one were to design/build/purchase a high quality, low loss passive xover, this still doesn't take into account phase shifting (which Eric quickly pointed on) as the voicecoils of the drivers heat up! Nor the phase shifts caused from "less than ideal ie multiple baffle" driver mounting locations.

This is why for the past several years now I've been preaching to run active. As 12v audio enthusiasts, we are fortunate to have really nice processors that can account for almost all of these shorcommings, and for very reasonable prices! Add that we can also typically get nice gear (more amplifier channels ) for dirt cheap these days and now all it takes is a little effort on the installers part!

[shawn k]

Consider these three setup possibilities...

System A has a single 50W x 2 amplifier running a pair of components using their included passive crossovers.

System B has a the same exact 50W x 2 amplifier running on the midranges from the previous system, and another 25W x 2 (same brand and line) amplifier running on the tweeters from the previous system, with an active crossover being used.

System C has a pair of the 25W x 2 amplifiers from System B running the midranges and tweeters in an active setup like System B.

Here is what you will find...

System C will not be nearly as loud as the previous systems. It might still sound good, but if the owner had a chance to compare it to System A or System B, they would not be all that happy with their investment.




System A and System B will be just as loud as each other, as perceived by the human ear. There is potential for System B to be louder when measured by a precision SPL meter, but there is also potential for System A to actually be louder. In rare instances the combination of the loudspeaker drivers and the passive crossover network can actually lower impedance, thus drawing more current. Don’t quote me on this, but I think the term would be the system is acting in “resonance”.

Since System B is likely no louder than System A, I fail to see how System B could ever be more efficient. The addition of a second amplifier (no matter what the power), is still introducing more power into the system to get the same result.

Now, there is indeed potential for System B to sound better than System A. But, this is going to be so depended on personal opinion, I see no way to ever prove anything. Just as system B could sound better than A, the inverse could be true as well. It would depend on just how well the active setup turned out, or how well the passive setup was designed. One could easily sound better than the other.

Damn bro... I was agreeing with you untill you made this last post

[ttocs]

I disagree that x-overs do not get warm as I have seen them melt before and also felt them when they were warm. I can't remember where I heard it but I was taught you can figure the cross-over will suck up and burn off up to 25% of the input power. And as they said if you have 50 watts going to the woofer portion you do not need 50 going to the tweet.

good discussion though...

[Eric D]

If you run a crossover rated at 50W with 150W, chances are it will melt. The components have their limitations. But, then again, so do the drivers as well. I have seen a heck of a lot more smoked tweeters than I have seen smoked crossovers.

Shawn, it is fine you disagree with me, but instead of just disagreeing, how about you explain yourself? Maybe I can learn something, and maybe others reading this will learn something.

I fail to see how a 25W amp will be louder than a 50W amp, just because the system is active. Since the passive crossover is very little loss, twice the power will win out easily.

If you wanted to make the argument that a 90W x 2 active system is better than a 100W x 2 passive, I would be more inclined to consider agreeing. But to think a 25W system could ever compete with 50W (assuming same speakers, amp brand and line) is laughable.

For anyone else reading this who may be interested, consider this...

If a passive crossover wastes power, it has to do something with it. That power would have to become heat. It does not vanish into a black hole. So, if you put an IR thermal probe on the components, you can measure their heating. You will find caps and coils heat very little (dependent upon how close you are running them to their limits), and resistors have the most heating. None of this heating is significant compared to the heating in the speakers voice coil (where all the power is really ending up).

25% loss in a crossover sounds pretty extreme to me. Honestly if that were true, I really don't think anyone would be making passive crossovers. Speakers themselves are VERY inefficient. Last I remember they are around 1%. To get any actual output, you need to have as little losses upstream as possible. 10% sounds more reasonable, and if you calculate that out, you are looking at only 1db of acoustic loss at the speaker. Trust me, you won't hear 1db of loss. It takes about 3db to perceive anything.

With a passive crossover you will loose damping (the ability of the amp to control the speaker), however, my argument has for the most part always been that for the average car audio user, they are going to get better results with a passive (factory unit) than trying their own active setup. It does not matter how much loss of damping you get with a passive, if you have the wrong crossover points, slopes, and phase, the best active will still sound worse. Most people simply don't have the equipment resources to develop a correct active crossover.

On the flip side though, to get back to the whole point of this thread, I think starting with an active crossover for a DIY guy is the way to go, then once you get your data where you want it, use it to make a passive crossover. This is exactly the method we used at Rockford Corporation to design the crossovers for our speakers. We had a very expensive digital crossover which would let us pick frequency, slope, and even phase. We could actually design digital filters which could not be built in the passive world. Once we settled on something we would build a passive version, and then tweak the values up and down based on extensive frequency response testing and listening sessions.

[ttocs]

actually the cross overs I saw melted looked as though it was the coil that was heated and caused the problem. Its hard to tell afterwards but to see the plastic cover looking like it was almost liquid and formed perfectly over the coil.

[Eric D]

actually the cross overs I saw melted looked as though it was the coil that was heated and caused the problem. Its hard to tell afterwards but to see the plastic cover looking like it was almost liquid and formed perfectly over the coil.

I have seen this exact same failure myself. In the examples I have seen, the coil was thin gauge (maybe 24ga wire), and the speaker system was over powered. At some point the coil will go into thermal runaway. Just like a light bulb in a tweeter protection will have almost no resistance during normal operation, but rapidly increase resistance once a current threshold has been reached, an inductor will do the same. When it does, the plastic housing (typical on cheap inductors) will become goo.

[shawn k]

Shawn, it is fine you disagree with me, but instead of just disagreeing, how about you explain yourself? Maybe I can learn something, and maybe others reading this will learn something..

Ok fine, here we go even though time and time again I give good valid info and for some fucked up reason you just tend to ignore it.

I fail to see how a 25W amp will be louder than a 50W amp, just because the system is active. Since the passive crossover is very little loss, twice the power will win out easily.

If you wanted to make the argument that a 90W x 2 active system is better than a 100W x 2 passive, I would be more inclined to consider agreeing. But to think a 25W system could ever compete with 50W (assuming same speakers, amp brand and line) is laughable..

I fail to see how a 25w amp can be louder than a 50w amp as well!!! But I never argued that! I was comparing a 25w x4 to a 50w x2! NOT THE SAME ARGUMENT NOW IS IT!!?? Yet again you fail at reading posts and arguing on the facts! It's getting really tiring man!

For anyone else reading this who may be interested, consider this...

If a passive crossover wastes power, it has to do something with it. That power would have to become heat. It does not vanish into a black hole. So, if you put an IR thermal probe on the components, you can measure their heating. You will find caps and coils heat very little (dependent upon how close you are running them to their limits), and resistors have the most heating. None of this heating is significant compared to the heating in the speakers voice coil (where all the power is really ending up)..

Passive components do heat up (especially inductors)! Even the expensive ones. I've seen very high end crossover designs with heat sinks on the inductors in order to balance the overall temperature between two or more coils in order to minimize value swings as the coils heat up. Now just because these components dont create nuclear fusion doesn't mean they don't heat up at all. ANY heat means a loss of power!

25% loss in a crossover sounds pretty extreme to me. Honestly if that were true, I really don't think anyone would be making passive crossovers. Speakers themselves are VERY inefficient. Last I remember they are around 1%.

Yes, speakers are very ineffiecient as a transducer. And yes, approximately only 1-2% electrical energy is transduced into acoustical energy.

To get any actual output, you need to have as little losses upstream as possible. 10% sounds more reasonable, and if you calculate that out, you are looking at only 1db of acoustic loss at the speaker. ..

Your calculations here are inconclusive! 10% loss of how much power and referenced to what equals 1db? Too little information

Trust me, you won't hear 1db of loss. It takes about 3db to perceive anything..

Good! I'm so fucking glad you said this! Going back to your A, B, C (which did not make much sense btw) systems from your previous post you state: "System C will not be nearly as loud as the previous systems. It might still sound good, but if the owner had a chance to compare it to System A or System B, they would not be all that happy with their investment."

How the fuck will System C be "not nearly as loud" as the previous systems!!?? C and A are identical power! C just splits the power evenly between the two drivers! Even "if" the mid was recieving TWICE or HALF the power from the amp, that's only a 3db difference and...... It takes about 3db to perceive anything" (your words) So even with the mid recieving only half the power, it's still only barely noticable. Yet you make it sound like one system is going to be significantly louder than the other one!

With a passive crossover you will loose damping (the ability of the amp to control the speaker), however, my argument has for the most part always been that for the average car audio user, they are going to get better results with a passive (factory unit) than trying their own active setup. It does not matter how much loss of damping you get with a passive, if you have the wrong crossover points, slopes, and phase, the best active will still sound worse. Most people simply don't have the equipment resources to develop a correct active crossover.

Not on topic

On the flip side though, to get back to the whole point of this thread, I think starting with an active crossover for a DIY guy is the way to go, then once you get your data where you want it, use it to make a passive crossover. .

Holy shit! That's completely assbackwards man!

This is exactly the method we used at Rockford Corporation to design the crossovers for our speakers. We had a very expensive digital crossover which would let us pick frequency, slope, and even phase. We could actually design digital filters which could not be built in the passive world. Once we settled on something we would build a passive version, and then tweak the values up and down based on extensive frequency response testing and listening sessions.

[/quote][/quote]


Well yeah man no shit! You're not comparing apples to apples. Rockford isn't a "DIY" guy. They build their xovers out of necessity to easily sell component sets, NOT for best perfromance!


I'm also glad you brought up (yet again) that you worked for Rockford! What exactly did you do there??? I'm not sure if you (personally) were involved with all of this xover designing or not, but if you were then.......... damn dude... You should know this shit!!!!

[Francious70]

Good lord it's been a while since I've seen a discussion like this.

Just remember Eric, don't get pissed

[Mackenzie]

Didnt expect to see all this... I really Just wanted to keep amps minimal, and keep it less complicated. My system will be loud, so I just wanted an efficient mid, and a tweet that can take abuse. Im going to search around, and also see what madisound recommends aswell. Pricing if I read it right was 30 per crossover, or for both, not sure. The drivers can be had for pretty cheap, so for 200 or less I could have a much better front stage.

[shawn k]

Didnt expect to see all this... I really Just wanted to keep amps minimal, and keep it less complicated. My system will be loud, so I just wanted an efficient mid, and a tweet that can take abuse. Im going to search around, and also see what madisound recommends aswell. Pricing if I read it right was 30 per crossover, or for both, not sure. The drivers can be had for pretty cheap, so for 200 or less I could have a much better front stage.

That's cool man. I understand the need for minimizing amps. There are certain requirements for every system. Curious which drivers you have decided to go with? Any links? I commend you for trying the DIY route with picking raw drivers. You can more often than not have better performance for less $$ by going this route. I'm sure the crossovers Madisound builds are nice, but I can't see that they will be anything "super" nice for the $30 range. Even a 6 or 12db slope (minimul parts) can run much MUCH more than that when using high-end components. All in all, I'm sure they will do what you need.

[Eric D]

OK, lets give it one more shot...

System A again has the 50W x 2 amp with passive crossovers on a set of components. I can add a bit of math here to explain things better. 50W x 2 into 4 ohms means the amp will do about 14V per channel prior to clipping.

And as before System C has a pair of the 25W x 2 amplifiers from System B running the midranges and tweeters in an active setup. Since each amp can do 25W x 2 into 4 ohms, the amp will do about 10V a channel prior to clipping.

Now, for the sake of argument, our crossover is a 1st order passive at a point of say 2kHz. The active is set to the same point.

If we play a 100Hz 0db tone through our setup (with all gains set for no clipping), we will measure 14V into the passive crossover, and 14V at the midrange terminals, and maybe 0-1V at the tweeter terminals (if that). This is for System A. So, with a 100Hz tone, the midrange will be getting 50W in this system.

Now, in System C, if we play the same 100Hz tone, we get 14V out of the low frequency amp which would be 14V measured at the terminals of the midrange. The is only 25W, or half the power of System A.

Now for tweeters. If we play a 10kHz tone on both systems, we will get 14V at the tweeter on System A, and only 10V at the tweeter on System C. System C will be half the power.

As for for db, 1db is not perceivable, but 3db is. System A will be 3db louder than System C.

This is because in System A, you have 50W to the components no matter the frequency. Near the crossover point, the power becomes divided between the drives, and their acoustic powers add together.

Even though System C has 50W a channel total, you never get any more than 25W of output, as one amp is doing nothing for low frequencies, and the other is doing nothing for high frequencies.

Sure, System C "might" sound better than System A. That is a very big "might" though. In a car going down the road 25MPH+, with no Dynamat, etc, it will never sound any different. But, I am willing to say that System C has the "potential" to sound better.

Now, I worked in car audio for many years, but never in any big city, where we would get any "high rollers" in car audio. So, my experience could be different than others. Here are my findings...

System A costs less than System C. One 50W amp is likely less than a pair of 25W amps. Also, adding the active crossover adds cost, but a lot of amps have them build in, so I won't count that. And for the sake of argument, I am assuming the customer bought a nice set of components originally, which included the crossover, and he chose not to use the passive for System C.

With all this in mind, if one guy owns System A, and the other owns System C, the guy with System A is going to be a lot happier. Sure, the guy with System C can go on and on about the technical aspects of his installation, but 95% of the population will sit in his car and say "I like the other guy's setup (System A) better". That fact that System A is twice as loud would win over a huge portion of the population (sadly).

[shawn k]

Eric, I'm sorry man, but you really need to stop. The more you try to dig yourself out fo this hole you've dug is only making it worse!

OK, lets give it one more shot...

System A again has the 50W x 2 amp with passive crossovers on a set of components. I can add a bit of math here to explain things better. 50W x 2 into 4 ohms means the amp will do about 14V per channel prior to clipping.

And as before System C has a pair of the 25W x 2 amplifiers from System B running the midranges and tweeters in an active setup. Since each amp can do 25W x 2 into 4 ohms, the amp will do about 10V a channel prior to clipping.

Now, for the sake of argument, our crossover is a 1st order passive at a point of say 2kHz. The active is set to the same point.

If we play a 100Hz 0db tone through our setup (with all gains set for no clipping), we will measure 14V into the passive crossover, and 14V at the midrange terminals, and maybe 0-1V at the tweeter terminals (if that). This is for System A. So, with a 100Hz tone, the midrange will be getting 50W in this system.

Now, in System C, if we play the same 100Hz tone, we get 14V out of the low frequency amp which would be 14V measured at the terminals of the midrange. The is only 25W, or half the power of System A.

Now for tweeters. If we play a 10kHz tone on both systems, we will get 14V at the tweeter on System A, and only 10V at the tweeter on System C. System C will be half the power.

As for for db, 1db is not perceivable, but 3db is. System A will be 3db louder than System C.

This is because in System A, you have 50W to the components no matter the frequency. Near the crossover point, the power becomes divided between the drives, and their acoustic powers add together.

Your analogy here absolutely 100% does not apply to the real world! The ONLY way to validate this state is with test tones/sine waves! WE DON'T LISTEN TO SINEWAVES MAN! When music is played (real world) through system A, obviously the tweeter will be playing it's assigned portion of audio. This indefinitely means that a chunk of the voltage or power (50w in this case) has to be applied to the tweeter in order for it to perform. Therefore the mid indefinitely CANNOT be driven with the full 50 watts!

With an active system, one does not have to worry or account for a voltage drop to ANY of the drivers since each has its very own channel to drive it! Now also for the sake of argument... before I was comparing a 25wx4 to a 50wx2. Obviously one doesn't necessarily have match the power for different drivers. You can easily enough run a 50wx2 to the mids, and a different amp, say 25wx2, could run tweeters if one wanted to.
^^
This is also yet another reason why running active is beneficial. In the real world, most mids are not as sensitive as tweeters. This can easily be rectified (in an active system) by either reducing the output of the tweeter amp, and or by simply using an amplifier with lower power than the mid amp. The only way, and often used, to cut the output in a passive crossover is to utilize high power resistors. Which ultimately is a waist of power.

Now, I worked in car audio for many years, but never in any big city, where we would get any "high rollers" in car audio. So, my experience could be different than others. Here are my findings...

System A costs less than System C. One 50W amp is likely less than a pair of 25W amps. Also, adding the active crossover adds cost, but a lot of amps have them build in, so I won't count that. And for the sake of argument, I am assuming the customer bought a nice set of components originally, which included the crossover, and he chose not to use the passive for System C.

Sorry, but there are way too many assumptions here to prove/disprove anything!

With all this in mind, if one guy owns System A, and the other owns System C, the guy with System A is going to be a lot happier. Sure, the guy with System C can go on and on about the technical aspects of his installation, but 95% of the population will sit in his car and say "I like the other guy's setup (System A) better".

HOLY FREAKN' ASUMPTIONS BATMAN.... ARE YOU SERIOUS???

That fact that System A is twice as loud would win over a huge portion of the population (sadly).

System A is NOT "twice as loud"!!!!! It takes an aproximate 10db for humans to perceive double the output! Even if (which it's not) system A was 3db louder then system C then the difference would only be slighty noticable... NOT TWICE AS LOUD

[kg1961]

maybe we are way off topic but the question was did anyone have madisound custom builfd your crossover?