Crossovers Passive vs Active

[Chad L 1]

Question about the use of amps crossovers and sound processors. Is it best to go all active not at all or combine?? Are amp filters as good as sound processors? 

When you buy a component speaker system you are paying for a crossover too. More expensive units have better crossovers. It’s been suggested that these crossovers use up power so not using them and using HPF and LPF on your amps is the better way to go. An alternative method is using a digital active crossover that can be programmed. 

Different methods are also to influence phase shifts that can create cancellation  or have better frequency curves. 

The cons would be a dedicated amp just for tweeters and one for mids and one for subs so instead of a 4 channel amp driving 4 pairs it would drive the mids on two channels and two channels for the tweeters then not using the expensive crossover that came with the speakers. 

I’m running everything thru an Audio Control DQX with sub filter crossover point and EQ that is separating the signal at 90hz which I can adjust. Then thru a programmable crossovers The component and coax speakers are all actively crossed between subs and mids but I am using factory crossovers still. I’m assuming they are only helping tweeters but guessing they may have a filter for the mid too? 

Do you think I am negating phase advantage by leaving factory filters in? Is the phase pollution not disruptive in high frequency so phasing mids and Subs is sufficient?

 I’m bi amping a pair of JBL competition speakers that has a jumper to remove in the crossover when doing this I am also using amp HPF and running other tweeters off all 4 channels. The JBL owner manual goes into great details about phase shifts and axis to explain what this crossover is doing to help  

is there a better way to measure it sounds going to me but who knows?

 

[///M5 2,833]

I would never use stacked crossovers.  Every crossover has a phase and magnitude response.  When you use both the signals sum.  Summing two signals that are altered of course will increase the constructive and desconstructive interference.  It can be really damaging to the response.

It has the same effect of playing multiple drivers on the same frequencies.  For clarity and quality this should be avoided as much as possible.  This is exacerbated in a car due to all the nasty reflecting planes.  It is bad enough to have to drive a driver into the comb filtering domain, but then adding another or further interference in the crossover is terrible.

The other aspect of this of course is that in general passive car audio crossovers are made with uber cheap components and designed for an "average" install.  This is somewhat absurd since there is no such thing as an install that is exactly like another.  This means that the passive crossover was never a good choice for any vehicle ever to begin with.  If you want to use a passive crossover and have it really work you should design the passive crossover using in situ measurements in the installed location.  Anything else is EASILY surpassed with even a simple processor like a miniDSP.

Last comment on active processors.  I would avoid any ones with analog front ends.  Turning a knob to dial in the frequency response or eq was fine in 1985, but today it is absurdly inaccurate and makes no sense whatsoever.  I would always prefer to have control from the drivers seat as well.  The more you can adapt as you sit in the listening location of the car the better.

[Chad L 1]

Speaker need some form of crossover so a quality crossover is ok? A single capacitor is not the same as a filter system. I post the owner manually of my JBL that explains its function. 

Is there info with crossovers in relationship to systems with a sub. The crossover supplied with the speakers manages those but by adding a sub it’s creating a 3 way system that needs another crossover? A good head unit has a sub channel is that a filter or crossover before the speakers? I don’t think it takes away from the other channels unless using HPF LPF? 

 Using an active crossover or DSP with a separate sub channel is a crossover separating the 30-90(120) front the source and allowing the component speakers or coax handle the rest. It’s possible to add an additional active crossover for the tweeters but a quality passive could be ok with good placement and using EQ to compensate for location or reflection?

a good system should be adjusted to be measured flat? Meaning adjusted for environment and equipment used? Or to a personal preference? Then adjusted to compensate for source material or again change of taste. For example my talk radio settings are different from Led Zeppelin or Alaska Thunderfuck but I don’t need to reconfigure my crossovers or speakers. Some songs like more or less of something. 

The concept that multiple speakers diminishes sound quality hasn’t been properly explained to me. If that was the case one 4x10 on the dash would still be considered hi fidelity. Stereo is multiple speakers. Separate tweeters are separate speaker. Is one woofer better than two? 6 would be terrible? 

[///M5 2,833]

2 hours ago, Chad L said:

Speaker need some form of crossover so a quality crossover is ok? A single capacitor is not the same as a filter system. I post the owner manually of my JBL that explains its function. 

Quality crossover and car audio crossover is an oxymoron.  A single cap can be a crossover, but a simple one with a 6dB slope.  The manual didn't post right, but I don't need one.  Designing crossovers is not rocket science, but a good one is usually as expensive if not moreso than the drivers you use.

3 hours ago, Chad L said:

Is there info with crossovers in relationship to systems with a sub. The crossover supplied with the speakers manages those but by adding a sub it’s creating a 3 way system that needs another crossover? A good head unit has a sub channel is that a filter or crossover before the speakers? I don’t think it takes away from the other channels unless using HPF LPF? 

Any and EVERY driver should have a crossover on it.  Otherwise it is going to be playing all frequencies.  20Hz in a tweeter is worse than 5kHz in a sub, but your response will be a hot mess if you don't use a crossover to optimize what speaker plays what.

3 hours ago, Chad L said:

Using an active crossover or DSP with a separate sub channel is a crossover separating the 30-90(120) front the source and allowing the component speakers or coax handle the rest. It’s possible to add an additional active crossover for the tweeters but a quality passive could be ok with good placement and using EQ to compensate for location or reflection?

A quality passive and a well setup active will mimic each other perfectly.  They are electronically analogous.  The only problem is you do not have good passives so your question is moot.  EQ is also not for compensating for location or reflection.  It is mean to allow you to cut out anomalies in the system.  Those could be caused by either of the above, but it is a last resort not a first step.

3 hours ago, Chad L said:

a good system should be adjusted to be measured flat? Meaning adjusted for environment and equipment used? Or to a personal preference? Then adjusted to compensate for source material or again change of taste. For example my talk radio settings are different from Led Zeppelin or Alaska Thunderfuck but I don’t need to reconfigure my crossovers or speakers. Some songs like more or less of something. 

Flat?  NEVER.  Why do you care what the response of your stereo is if YOU find it perfect.  You should also generally NOT have to adjust for source material.  That shows that the calibration of your system is way off.  Do note that of course you will hear differences in sound, but it shouldn't be as drastic as you state.  

3 hours ago, Chad L said:

The concept that multiple speakers diminishes sound quality hasn’t been properly explained to me. If that was the case one 4x10 on the dash would still be considered hi fidelity. Stereo is multiple speakers. Separate tweeters are separate speaker. Is one woofer better than two? 6 would be terrible? 

One 4x10 sucks donkey.  In fact there is no such thing as a good 4x10.  I have to apologize in your first thread I really, really, really thought you were a troll posting misinformation and confusion to get a reaction.  I now see that it is regrettably real.

To answer this last question, I want to start with a question to make sure I go back far enough.  Do you understand constructive and deconstructive interference?  If not, google it and then come back with questions regarding it and it will make it very easy to clear up why multiple drivers are not a good thing.  You have an amazing amount of work in your car and have done a really nice job installing things; however, the information that led you to think you were doing something that would help your sound is really far off from reality.  Somehow along the way someone really confused you and caused you to spend a superfluous amount of money to have very lackluster results.  We can fix it, but first you need to understand why.

[Chad L 1]

y

9 hours ago, ///M5 said:

Quality crossover and car audio crossover is an oxymoron.  A single cap can be a crossover, but a simple one with a 6dB slope.  The manual didn't post right, but I don't need one.  Designing crossovers is not rocket science, but a good one is usually as expensive if not moreso than the drivers you use.

Any and EVERY driver should have a crossover on it.  Otherwise it is going to be playing all frequencies.  20Hz in a tweeter is worse than 5kHz in a sub, but your response will be a hot mess if you don't use a crossover to optimize what speaker plays what.

A quality passive and a well setup active will mimic each other perfectly.  They are electronically analogous.  The only problem is you do not have good passives so your question is moot.  EQ is also not for compensating for location or reflection.  It is mean to allow you to cut out anomalies in the system.  Those could be caused by either of the above, but it is a last resort not a first step.

Flat?  NEVER.  Why do you care what the response of your stereo is if YOU find it perfect.  You should also generally NOT have to adjust for source material.  That shows that the calibration of your system is way off.  Do note that of course you will hear differences in sound, but it shouldn't be as drastic as you state.  

One 4x10 sucks donkey.  In fact there is no such thing as a good 4x10.  I have to apologize in your first thread I really, really, really thought you were a troll posting misinformation and confusion to get a reaction.  I now see that it is regrettably real.

To answer this last question, I want to start with a question to make sure I go back far enough.  Do you understand constructive and deconstructive interference?  If not, google it and then come back with questions regarding it and it will make it very easy to clear up why multiple drivers are not a good thing.  You have an amazing amount of work in your car and have done a really nice job installing things; however, the information that led you to think you were doing something that would help your sound is really far off from reality.  Somehow along the way someone really confused you and caused you to spend a superfluous amount of money to have very lackluster results.  We can fix it, but first you need to understand why.

We agree a 4x10 suck that’s what is factory in the Saab. You missed the point that claiming adding speakers is good not bad like your trying to persuade. You loose credibility when you make absurd comments and you make many. First is to claim my results are lackluster having never heard it it simply trolling. You feel using audio controls DSP and 62X active crossovers are not good and moot? Your not looking smart on this. In fact you don’t look smart on anything. You only look like someone that likes to argue and besides trying to be insulting you’ve only proved you can’t validate what you claim. You make one false claim after another. Anyone that claims to be an authority can back it up with credentials credibility or show supporting articles you haven’t. You can comment more but you really need to bring something useful or educational otherwise you’re just a troll jumping on people and posts. I’m sad you have offered so little useful information. I’ll post an article I read that calls you a snake oil salesmen trying to be all knowing. Misusing information 

http://sound.whsites.net/ptd.htm

ABSOLUTE PHASE LUNATICS 

If we believe the 'absolute phase' lunatics, this would not be the case, so your partner may sound like your partner in one part of the room, but sound like the milkman in another. We all know that this doesn't happen - the tonal structure of a sound does not rely on the phase integrity of the received sound, only the relative amplitudes of the fundamental and harmonics. So a speaker that has perfectly flat frequency response but is not 100% phase coherent will sound the same as one that is also flat, but totally phase coherent. This does not include colouration caused by the cabinet or drivers - of course these are important. Assume the same enclosure, same drivers, but a phase shift applied to one, and not the other.

In isolation, they will sound the same. Put them together, and you will hear strange reinforcements and cancellations as you move about. This is relative phase between separate sound sources, and is very audible indeed. What we need to concern ourselves with is relative phase between sources, not absolute phase or phase shift. Two amplifiers with different phase responses used as a stereo pair will sound terrible if the shift is sufficient. Use two of the same amplifier, and there is no problem.

Absolute phase is inaudible within reason - a 3,600° phase shift represents a time delay that is significant, but a 360° phase shift will not be heard. Inverting a signal (e.g. reversing the connections to a loudspeaker driver) creates a 180° phase inversion, but this is not the same thing as a 180° phase shift! This is a point missed by many.

Relative phase is audible, depending on the amount, the frequency and the context. Two speakers side by side with 90° phase shift between them will sound dreadful - and the sound will change as you move about. The relative phase of two musical instruments playing in harmony makes the sound you hear - take away the phase shifts, and it will sound flat and lifeless.

Relative phase is audible, depending on the amount, the frequency and the context. Two speakers side by side with 90° phase shift between them will sound dreadful - and the sound will change as you move about. The relative phase of two musical instruments playing in harmony makes the sound you hear - take away the phase shifts, and it will sound flat and lifeless.

There have been many tests and experiments to look at phase shifts within the audio band, and whether they are audible. Under controlled laboratory conditions (or using headphones), there is strong evidence that with single (complex) tones, there is an audible change. However, in a listening room with speakers reproducing music, there is little evidence that phase shifts are audible with the vast majority of recorded material.

If there is enough phase shift, this gives rise to group delay, which may become audible if it exceeds the threshold of audibility. Fortunately, these thresholds are generally well in excess of the delay caused by any commonly used filter or crossover network. See the section on group delay for more on this topic.

An example of a pair of very typical all pass filters is shown in Figure 14. These are connected differently so I could show the different behaviour (not actually different, the phase of one is simply reversed from the other).

Relative phase is audible, depending on the amount, the frequency and the context. Two speakers side by side with 90° phase shift between them will sound dreadful - and the sound will change as you move about. The relative phase of two musical instruments playing in harmony makes the sound you hear - take away the phase shifts, and it will sound flat and lifeless.

There have been many tests and experiments to look at phase shifts within the audio band, and whether they are audible. Under controlled laboratory conditions (or using headphones), there is strong evidence that with single (complex) tones, there is an audible change. However, in a listening room with speakers reproducing music, there is little evidence that phase shifts are audible with the vast majority of recorded material.

If there is enough phase shift, this gives rise to group delay, which may become audible if it exceeds the threshold of audibility. Fortunately, these thresholds are generally well in excess of the delay caused by any commonly used filter or crossover network. See the section on group delay for more on this topic.

I was going to post more but you can read it yourself 

[///M5 2,833]

You didn't look up interference

Credibility comes from knowledge.  I don't like sharing things like that because I believe the answers are in the meat of the conversation...but you aren't reading the conversation with anything but blinders on so I will. I am a degreed Acoustician.  I do consulting work within the audio industry.  You name a big speaker manufacturer in the US and I've had engineers there ask for my assistance in development.  This includes integration in cars as well.  I run a company that has over $10M in audio and vibration measurement equipment in North American alone.

You are missing the fundamental basis for understanding acoustics.  I am trying to help, but you are getting defensive instead of reading.

[j-roadtatts 1,129]

 Why would I post up more links or information for you when I can tell you did not read the two links I left in your biuld log? The one clearly went over speaker applications and crossovers.  The second one clearly went over crossovers and reflections.

 As far as improving on what you have.

1.  Get the gains and xover set right. If you have questions please ask.  Try to keep the question short and to the point without coloring it with the unneeded information.  Read the links and if you did reread them.

2.  Stiffen up the mounting points of all the woofers. You are losing a lot of acoustical energy in the midbass range. I do not need to hear the car to tell you this.  Mount wooden baffles or braces on the backside of the  panels will be the most cost-effective.  Where you think you only need two layers of sound dampener, put four.  You can test this now by applying pressure/placing your hand on the panel next to the speakers when you are playing some midbass heavy music.  See how it changes the sound!

3.  Deal with reflections. Reflections have their own time signature.  No amount of settings will get rid of this signature.  It must be done with manually by placing absorbent material over reflective surfaces. Such as a dash mat or covering hard surfaces with a soft material.  You can do testing now by placing towels or blankets over all the hard surfaces and see how it changes the sound!

4.  Lastly is to touch on the cancellation/constructive/distructive distortion and comb filtering. This comes in many forms such as distortion in the music source. Distortion introduced from other equipment in the sources line, such as high THD of amplifiers being driven at 2ohms.  Speaker companies even design  harmonic distortion into the mid bass range,  to make the speakers sound warmer.  

 So the things you could improve on other than understanding the above paragraph.  Install an acoustical barrier to block the back waves of the woofers. The back waves of the speakers interacting with the front waves, causing  cancellation/distractive/constructive distortion and comb filtering.  No real way to test this other than to know the speakers true acoustical signature from playing it inside of a enclosure in a controlled environment,  before installing it in the car!

 I know you're trying to get it to sound better now, as you willingly admitted to me you thought it sounded better before. 

[Chad L 1]

4 hours ago, ///M5 said:

You didn't look up interference

Credibility comes from knowledge.  I don't like sharing things like that because I believe the answers are in the meat of the conversation...but you aren't reading the conversation with anything but blinders on so I will. I am a degreed Acoustician.  I do consulting work within the audio industry.  You name a big speaker manufacturer in the US and I've had engineers there ask for my assistance in development.  This includes integration in cars as well.  I run a company that has over $10M in audio and vibration measurement equipment in North American alone.

You are missing the fundamental basis for understanding acoustics.  I am trying to help, but you are getting defensive instead of reading.

Maybe I don’t play well with others. I’ll read again 

[Infinite913 381]

Chad I feel you are going about this all wrong. Here is what needs to happen. Pretend your car has 0 speakers and you didnt do anything to it yet. This is where we want to help you from. To try and tell you how to make 700 speakers on 800 different amps work and sound good isnt going to happen over the internet or ever for that matter. We are trying to help get you on the right path and im sorry to say it but its going to take ripping out all your stuff and starting fresh(ya i know no one ever wants to hear that). If you were to come to my shop and ask me to help you with your car i wouldn't touch it unless it was to yank it all out and start fresh. I am a custom audio shop owner and have built over hundreds of walls and hundreds of enclosures and have had cars with 8 6.5s in eaxh door(check the basstro build in the logs). And it took me reading up on info M5 shared for me to know less is more and way better. 

 

So i said all that to say this. No one here is your enemy. No one here is going to make any money off you. Everyone here is taking time out to respond to your questions and concerns. No trolls here. But honestly i have been following you like a troll and I can say your not reading the info your being given. Your just going off your experience and trying to have us figure out a way for your car to sound better. J road and M5 have supplied you with all the proper information and links aswell. M5 told you to google and unless he has stocks in them than he will make 0 off your research ability. So Chad please take what we are saying with a grain of salt. It will help it taste much better. 

Edited March 2, 2018 by Infinite913

[///M5 2,833]

For audio help, I bill at $2k/hr.  Have customers lined up wanting to pay it.  Obviously here it is all con gratis.  It is a way for me to relax from the hustle of my job and help people learn.  Of course the first step in that is they have to want to learn.  Once that is established the rest is much easier.

[Chad L 1]

Thanks 

[///M5 2,833]

Read.  Ask questions.  Perhaps keeping your car out of it for examples will help.

[Jay-C76 333]

I know sometimes help may sound condensing, but if there was anyone I would ever trust on any website or forum when it comes to understanding audio acoustics it would be M5. 

Not to chastise you in anyway, I have never in my life seen so many drivers in an install at any competition I have ever been in whole only driving two 15" subs.

Best in show is awarded for a visual appearance not any type of physical audio accomplishment. 

You have some nice equipment to achieve what you are after, but you have created an insane amount of anomalies that will physically never yield good results other than visually.

Everyone who has posted above has had nothing but the best intentions of helping. Nobody will ever "spoon feed" you information because history has taught mankind that's not how one learns the "how & why".

I wish you all the luck but, if I were you I would not have so many drivers to try to blend with only two 15"  mtx subs. If it were six 15" subs maybe but what you are doing isn't working for a reason.

[Chad L 1]

You know they said to the Wright Brothers “That thing will never fly.” Even after it did. I respect your all options everybody has one. Saab is a peculiar car it was made during 6 months of darkness.  The hood opens backwards the engine is in backwards the transmission is sideways the drive is the front wheels. While it was innovative and a leader in technology the first car with turbo it was always second guessed by critics. That’s what critics do isn’t it? That’s what you do isn’t it?  You’re not a very good critic if you said something was good are you? 

I’m sure you guys are the best at taking door panels out and swapping speakers or cutting fiberboard and covering it with vinyl. I will never match your ability to sell the equipment I’ve seen on your site. I doubt any of you have installed a system in a Saab or at least a Saab 900. My original point. A car with 4” danish speakers in the dash and open 4x10 in the rear that didn’t sound too bad with a Kicker sub in the back. Kind of what you do? Throw a sub under the seat or in the back? No I know you carefully install speakers with good mark ups, amps that are one ohm stable in tried and true methods. Build a door panel on a Silverado I could maybe do too. Way cool props  

I’ve never seen an install of speakers to a Saab 900 in what would be normal factory locations like Dash doors and rear seat like I have done. I’ve really out done you and everyone else there. Choice of amps speakers crossovers number of drivers are mute points when just considering this has never been done so simply and creatively. It’s the kind of thing where you say why didn’t I think of that but I did. It’s pure innovation. It’s art. It’s holy fudge wage you open a door. Well done. An inspiration to anyone  doing DIY thank you. You all haven’t heard it so you’re opinions on the sound quality is a consideration but invalid. Most of your argument is invalid in my opinion but maybe it sells you services to that guy with a Beemer. 6 Subs really? How do you know I haven’t tried?? The system delivers even with no subs. It was nice  with a 10” Ballistic Kicker wired to 2 ohms in a vented box and 1200 watts. But I can make it more annoying to the guy in the Beemer next to me with two respectable 15” MTX thunder. The fact it annoys you is a sign of “Well Done” It can rock the house very nicely Led Zeppelin blows people away and the imaging moves all around with the Whole Lotta Love. It plays jazz big band and Royal Philharmonic very enjoyably. It even plays solo piano in concert like reproduction. I think it’s not a bad look either. I feel you lost a love for car audio enthusiasts. The joy they have bringing something together. You’re all about the money and since this car isn’t making you any are against it. You’re trying to find a way to use it get a customer. You’re salesmen. It’s sales pitch for 2K an hour. I get it. 

 

[///M5 2,833]

So you still didn't read about interference.  A Waves 101 class would be eye opening.

[Miller 0]

After reading your last post, I went back through this topic and your other topic to see if anyone was a "salesman" and being "all about the money", yet I was unable to find a single reference to that.  If anything, I saw most people trying to save you money by suggesting to sell a lot of equipment and use what you currently have in a different arrangement to make your experience even better.

We all start out somewhere and usually it is by trying to be as loud as possible with many speakers because it has quite the "wow" factor.  You being an innovator in that regard is not correct.  You doing it in a Saab 900 could possibly be correct, but I have not seen every install in a Saab 900 nor does it really matter to me.  What people are trying to tell you is that although they respect the install you have done, it can be made better while using the same components you have.  You believe your install is achieving something amazing and is an innovation, but what people are trying to tell you is that is not possible based on physics and science.  The information explains why your current install is actually hurting the overall system.

No one is is trying to be a snake oil salesman.  Instead they are actually trying to have you read and learn what makes a great sounding system.  I understand there were some troll comments thrown around in the beginning, but since then many links and suggestions have been made to try to help you achieve the best system you can with what you currently have.  Please educated yourself on the items that have been suggested.  At that time, maybe you will be able to ask questions on why people are suggesting the changes they have made rather than just blow them off.

Edited March 3, 2018 by Miller

[Jay-C76 333]

http://xtremerevolution.net/audio-101-on-off-axis-response/

 

Understanding this may help you figure out that just because something fits in a location without proper aiming you may get undesirable results.

Edited March 3, 2018 by Jay-C76

[j-roadtatts 1,129]

Honestly dude, I think everyone is jealous of your switches. That's some next level shit right there. Straight outta James Bond or back to the future! Not to mention I wish I could afford ALL that equipment. you have so many great ideas in that car, I hope someday I can be like you!!

[frogcase2002 393]

Funny shit man

[frogcase2002 393]

I honestly would really like to hear this system lol

[Aaron Clinton 2,372]

Closing this topic as OP has no intention of listening to any advice, as he proceeded to go on a massive, unhinged post reporting rant, followed by moving to twitter to bash my company and the products we carry.

[///M5 2,833]

Too bad considering his install was singlehandedly the biggest waste of money and confusion I have ever seen on the internet.  He REALLY needs help.