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Thread: Upgrading the E34 Stereo Tutorial

  1. #51
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    I don't but my CD43 showed up today... hoping for some enhanced audio output.

    and will this work with the CD43?
    http://boston.craigslist.org/gbs/pts/2455783898.html

    I have the stock original e34 540 specific PIO Changer which I read doesn't work with anything but the Alpine 5 HU.
    Last edited by jehu; 06-23-2011 at 01:25 AM.

  2. #52
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    Quote Originally Posted by Matt Z View Post
    Ok so keeping with the stock system. Does anyone know what the true rms rating for the stock system is? Not what the amp puts out but how much the speakers can handle.
    I don't know what the speakers are rated to handle but that is a function of the voice coil thermal rating. IOW, the power rating is based on the ability of the speaker to handle electrical current without overheating and melting the glue that holds the wire in the voice coil together.

    Here are the important parts. The power rating is based a full range signal being sent to the speakers. At least 50% of the power is in the bass frequencies. Using an active crossover with a decent slope of 12 db per octave or more protects the midrange and tweeter from potentially damaging low frequency power levels while allowing them to play much louder without distortion. Within reason, you could use high power amplifiers on these drivers and not have to worry about damaging them before you damage your ears. This same argument applies to the mid-bass driver in the kick panels if you use a subwoofer and active crossover between them. Restrict the range of frequencies sent to a driver to what is appropriate for that driver and you increase its ability to handle power.

    There is another very important factor. High power alone does not blow speakers. Distortion in the signal sent to the speakers is what damages them. A low power (15 watt) amp that is clipping, will blow a speaker before a 100 watt amp delivering a clean signal.

    Quote Originally Posted by jehu View Post
    I don't but my CD43 showed up today... hoping for some enhanced audio output.

    and will this work with the CD43?
    http://boston.craigslist.org/gbs/pts/2455783898.html

    I have the stock original e34 540 specific PIO Changer which I read doesn't work with anything but the Alpine 5 HU.
    Even if it works, the cable from the head unit to the CD changer is different in E34 and E39 vehicles. You need to run a new cable in your E34 to use this.
    Last edited by Mark185; 06-23-2011 at 10:51 AM. Reason: Automerged Doublepost

  3. #53
    Stereoinstaller1 is offline Senior Member Supporting Vendor
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    Such excellent audio discussion...amazing. Much respect for the level of knowledge here!

    Fellas, take a close look at the PPI PC 3.65C. With adapter plates to drop them in the stock locations of the E34 (LOTS of other BMWs as well) I think we may have a fairly cost effective winner.

    A 6.5" midbass with a 2" voice coil and a Kevlar cone? A NEW 2.25" midrange? Bring it, baby!

    I am so excited about the level of product coming out of Epsilon (Power Acoustik? YUK!) upper brands, and the attitude shown with their newer products...we just may have a resurgence of quality in the world of car audio.


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  4. #54
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    love this thread. so much great information. i learned a lot.




    sorry, thats all i got. just an audio enthusiast thats happy to have read some useful information.

  5. #55
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    Rethinking my approach

    The Lanzar crossover finally arrived but before I got a chance to measure its response and start setting it up, I decided to measure the voltage output of the C33 head unit and frequency response of the stock Nokia 2" midrange.

    The speaker outputs on the C33 have a max voltage output of 3.5 Volts RMS and peak voltage of about 4.2 volts. I tested this by recording a 1 KHz sine wave on a cassette and measuring the output with a Fluke Scopemeter. This is a fairly low output compared to modern head unit speaker outputs but is well suited for driving the input of the Lanzar crossover. A line level adapter should not be necessary. I will measure the input sensitivity of the Lanzar and see what voltage level overloads it, but for now, I think it will work with the stock head unit without any kind of level converter. This may not hold true for the CD43 head unit. It has higher output voltage and may require a level converter to keep from overloading the Lanzer inputs. There is a more expensive crossover made by Audio Control that has much better input circuits. It can handle anything up to 10 volts with ease. I think it is the 6XS. I did not select that because I was trying to keep the cost of this mod as low as possible.

    The second measurement is more of a problem. It turns out the stock midrange has a really poor frequency response and does not have much output below 1000 Hz. I was planning on crossing over to it somewhere between 250-500 Hz. That is not possible. I have attached a pdf with frequency response plots for both the stock midrange and a 2" speaker made by Peerless that is small enough to easily mount in our dash locations. The difference is significant. The Peerless unit has nice flat response from around 200 Hz all the way up 5 KHz. This can be purchased for about $14.00 from Madisound speakers. Notice that it has much higher output than the Nokia in the midrange frequencies. This improved efficiency means it will play louder with less amplifier power. I am not 100% certain it will work yet but it looks very promising.

    Bottom line at this point is that I do not think it is worth it to install active crossover and higher power amplifier if you do not also replace the midrange driver in the dash. If you don't want to replace the mid, it makes more sense to just do the amplifier bypass as described by AE. The only other approach that makes sense to me if keeping all the OEM drivers, is to install an Audio Control EQX between the head unit and the OEM amplifier. It has speaker level inputs, a 13 band equalizer, and a 24 dB per octave crossover that is adjustable by changing a inexpensive resistor pack. This could be set to keep frequencies below 100 Hz from the front speakers and you would install a powered subwoofer to handle everything below 100 Hz. The equalizer can be used to compensate for some of the frequency response problems up front. I see used EQX models on Ebay usually selling for $90-125. New ones are around $250-270. Add to that, the cost of a subwoofer and amplifier. This approach will undoubtedly sound better than stock. The down side is that this is hard to do if you don't have equipment to measure the frequency response. It is possible to set an equalizer by ear but it takes patience and some studying to get it right. If anyone is interested in this, I strongly suggest spending time on diymobileaudio.com studying the tutorial threads on tuning equalizers and crossovers.

    I am sure someone will ask about just replacing the Nokia mid with the Peerless mid without making other changes. I am sure you can do this but the crossover in the amplifier is not designed for this speaker and the response you will get is not something I can predict. It is likely to be much to loud compared to the tweeter and kick panel woofer because of its higher efficiency. A better passive crossover is really needed to make this work.

    I am going to evaluate this mid and a couple of other models and continue down the path of installing active crossover and a higher power amp.
    Attached Files Attached Files

  6. #56
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    If the Peerless speakers are compatible with BMW stock Speaker wiring method is it perhaps possible to just solder some value of resistor between the amp output and the speaker to adjust for the sensitivity and bring it within the range of the rest of the array or would that either not act in the way I assume or interfere with the amps output to the entire array?

    Last electronics course i took was as a freshman in High School in 1977..

    I ask because I have just installed a CD43..

  7. #57
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    Quote Originally Posted by jehu View Post
    If the Peerless speakers are compatible with BMW stock Speaker wiring method is it perhaps possible to just solder some value of resistor between the amp output and the speaker to adjust for the sensitivity and bring it within the range of the rest of the array or would that either not act in the way I assume or interfere with the amps output to the entire array?

    Last electronics course i took was as a freshman in High School in 1977..

    I ask because I have just installed a CD43..
    Very bad idea to put a resistor in series with anything other than a tweeter. It cripples the amplifier's capability to control the speaker cone. It also will not compensate for the fact that the crossover in the factory amp is not designed for a speaker with the extended frequency response of the Peerless driver. The Peerless will not blend with the other drivers without a new active or passive crossover.

    The CD43 doesn't really have any impact on whether or not you upgrade the midrange speaker. Its benefit is a higher, cleaner output voltage feeding the amplifier in the back. It also has a more extended frequency response on both FM and CD playback than the old head unit had with cassette and FM. The only potential problem with the CD43 is that its output voltage might be too high to connect it directly to the active crossover I selected for this project. The remedy is either a line level converter to knock down the voltage and match it to the capability of the Lanzar crossover or spend more money for a better crossover with speaker level input circuits such as the Audio Control 6XS.

    In this install, after I get the basics down, I am going to investigate using an Audio Control EQX equalizer/crossover in front of the Lanzar crossover. The EQX also has speaker level input circuits and includes a subwoofer crossover. I bought mine used about 10 years ago. Audio Control products are really well made equipment and I have no worries about using something this old.

    Here is some BMW head unit information from an old bulletin board that was a forerunner to forums like this. (Yes, I have been doing this a long time.)

    Factory Head Unit Deficiencies
    To: e36m3@Mailing-List.net
    Date: Tue, 28 Dec 1999 12:29:45 -0800

    Subject: [E36M3] RE:

    I am forwarding this I think the list can benefit from this information. I have been banging my head against the wall looking for the best solution in regards to a stereo upgrade to my 95 M3. This is the response I received from the horses mouth.

    Robert,
    Yes, I do know quite a bit about the E36 audio system, as I helped to design it while working as the Product Development Manager for BMW until recently.
    With regards to upgrading your audio system, the weakest link is currently
    (and unfortunately) the radio. In your 1995 E36, you have what is called the
    C33 platform, identifiable by having weather band feature.

    Since then, the unit has been upgraded 2 more times; the C43 and more recently the CD43. Although the C43 (still a cassette unit) is somewhat better than your C33, the CD43 is substantially better. The CD43, however, is an in-dash CD player. The major difference being the output voltage, which better drives the existing amplifier. All of these units will work in your vehicle with no modifications whatsoever; the power harness, everything, are direct plug-ins. What you currently experience is a low voltage output from the C33, which does not adequately drive (take advantage) of the on-board, external amplifier. Your unit also has a limiter on the upper frequency range in the FM mode, meaning that when you play FM, you never hear anything above 9 or 10K. This was because there was inherent noise from the engine that could not be attenuated, so the radio had to be attenuated. This hurt sound quality in the upper frequency range (sounds muffled). I eliminated the limiter altogether on both C43/CD43 platforms for US cars. Now the Radio drives the amp better and you can enjoy higher frequency output. These units will work w/o any noise problems in your car.
    Last edited by Mark185; 06-26-2011 at 11:41 PM. Reason: Automerged Doublepost

  8. #58
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    Quote Originally Posted by M20E34 View Post
    Such excellent audio discussion...amazing. Much respect for the level of knowledge here!

    Fellas, take a close look at the PPI PC 3.65C. With adapter plates to drop them in the stock locations of the E34 (LOTS of other BMWs as well) I think we may have a fairly cost effective winner.

    A 6.5" midbass with a 2" voice coil and a Kevlar cone? A NEW 2.25" midrange? Bring it, baby!

    I am so excited about the level of product coming out of Epsilon (Power Acoustik? YUK!) upper brands, and the attitude shown with their newer products...we just may have a resurgence of quality in the world of car audio.
    I'm interested in those speakers but the only thing that concerns me is the depth of the midrange speaker. Will that even fit in the dash on the E34??

    95 540i6 M Sport - 95 525it S52/OBD2 - 433k E36 328i5 - X5D that hit a pothole - IG: @justinmurray95

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    Quote Originally Posted by SmurfeN View Post
    for us europeans and a newbie like myself with no factory amp in the boot.. only the deck, kick panel speakers, dash speakers and rear shelf speakers... does any of this apply to us ? :P
    No, it does not as we don't have any amps in the way. We have clean cables from the head unit back to the speakers, so doing what you want is no problem really! Only pro we have lol.


    Quote Originally Posted by Mark185 View Post
    Yes, but how you install and wire this system may be different if your factory stereo wiring harness is different than ours. I am going to show how to use the existing wiring that runs from our head units to the rear amp. If the euro cars do not have this harness in place, you will have run your own cables from front mounted head unit to the rear and from the new rear amplifier to the speakers. It will increase the labor involved by a big margin. You can check your harness by looking for 4 or more sets of twisted wire pairs in the left rear 1/4 panel body cavity behind your trunk panels. If it is there, BMW should have installed some kind of plug to just loop the signals back to the front speakers without and amplifier. This would be very interesting to find out because the 'loop back' wiring if it exists could make this upgrade much easier for enthusiasts on both sides of the pond.


    No, we don't have any amps of such on some of our cars, it means that the speaker wires goes straight from the headunit to the speakers itself atleast on the basic optioned e34's over here.

  10. #60
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    Quote Originally Posted by Mark185 View Post
    Very bad idea to put a resistor in series with anything other than a tweeter. It cripples the amplifier's capability to control the speaker cone. It also will not compensate for the fact that the crossover in the factory amp is not designed for a speaker with the extended frequency response of the Peerless driver. The Peerless will not blend with the other drivers without a new active or passive crossover.

    The CD43 doesn't really have any impact on whether or not you upgrade the midrange speaker. Its benefit is a higher, cleaner output voltage feeding the amplifier in the back. It also has a more extended frequency response on both FM and CD playback than the old head unit had with cassette and FM. The only potential problem with the CD43 is that its output voltage might be too high to connect it directly to the active crossover I selected for this project. The remedy is either a line level converter to knock down the voltage and match it to the capability of the Lanzar crossover or spend more money for a better crossover with speaker level input circuits such as the Audio Control 6XS.

    In this install, after I get the basics down, I am going to investigate using an Audio Control EQX equalizer/crossover in front of the Lanzar crossover. The EQX also has speaker level input circuits and includes a subwoofer crossover. I bought mine used about 10 years ago. Audio Control products are really well made equipment and I have no worries about using something this old.

    Here is some BMW head unit information from an old bulletin board that was a forerunner to forums like this. (Yes, I have been doing this a long time.)

    Factory Head Unit Deficiencies
    To: e36m3@Mailing-List.net
    Date: Tue, 28 Dec 1999 12:29:45 -0800

    Subject: [E36M3] RE:

    I am forwarding this I think the list can benefit from this information. I have been banging my head against the wall looking for the best solution in regards to a stereo upgrade to my 95 M3. This is the response I received from the horses mouth.

    Robert,
    Yes, I do know quite a bit about the E36 audio system, as I helped to design it while working as the Product Development Manager for BMW until recently.
    With regards to upgrading your audio system, the weakest link is currently
    (and unfortunately) the radio. In your 1995 E36, you have what is called the
    C33 platform, identifiable by having weather band feature.

    Since then, the unit has been upgraded 2 more times; the C43 and more recently the CD43. Although the C43 (still a cassette unit) is somewhat better than your C33, the CD43 is substantially better. The CD43, however, is an in-dash CD player. The major difference being the output voltage, which better drives the existing amplifier. All of these units will work in your vehicle with no modifications whatsoever; the power harness, everything, are direct plug-ins. What you currently experience is a low voltage output from the C33, which does not adequately drive (take advantage) of the on-board, external amplifier. Your unit also has a limiter on the upper frequency range in the FM mode, meaning that when you play FM, you never hear anything above 9 or 10K. This was because there was inherent noise from the engine that could not be attenuated, so the radio had to be attenuated. This hurt sound quality in the upper frequency range (sounds muffled). I eliminated the limiter altogether on both C43/CD43 platforms for US cars. Now the Radio drives the amp better and you can enjoy higher frequency output. These units will work w/o any noise problems in your car.

    Interesting to hear the designer say the CD43 works with no noise . is there a difference between the 95 M3 and the 540 that would account for the 'Ticking' I had until disconnecting Pin #7 ?

  11. #61
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    there is probably a substantial difference in the length of the wiring harness in E34 compared to E36. They represent two different generations of electrical system design at BMW. I have the C43 in my touring right now and have no noise issues with it. I have the CD43 in my 328iC and no noise there either. Where did you disconnect pin 7? At the head unit?

  12. #62
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    Does anyone know why a stereo in a $50,000 almost V8 super-car sounds worse than a dodge minivan's of the same age???

  13. #63
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    Quote Originally Posted by BMH View Post
    Does anyone know why a stereo in a $50,000 almost V8 super-car sounds worse than a dodge minivan's of the same age???
    Engineering priorities. BMW design philosophy at the time was that killer stereo and good cup holders were only distractions to the real task of driving well at a brisk pace.
    Last edited by Mark185; 06-27-2011 at 01:21 PM. Reason: Automerged Doublepost

  14. #64
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    Anyone using the Image Dynamics under dash mini horns?

  15. #65
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    "vie shall poot 8 speakaz but none shall have aaahny bass!!!" "sie only peipel zat will be drivink sies car will listen to motzart!" "but what about mein tuba musik????" "I vont be able to hea mi deep notes!!"

  16. #66
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    Quote Originally Posted by Mark185 View Post
    there is probably a substantial difference in the length of the wiring harness in E34 compared to E36. They represent two different generations of electrical system design at BMW. I have the C43 in my touring right now and have no noise issues with it. I have the CD43 in my 328iC and no noise there either. Where did you disconnect pin 7? At the head unit?

    The connector inside the harness connector plug. I read someone had eliminated the ticking by taping over pin 7 but I found electrical tape just got pierced by the pin when pushing on the connector .

    I opened up the connector and the termination of the wire in the harness for pin 7 on the head unit was rotated while pushing it out with an implement. I pulled it out and away from the connector, taped that termination over and reassembled the plug.

    The ticking was heard at lower volumes. It was of a constant nature which didn't change in rate with fluctuations in RPM and did not increase with volume increase. It was for me very annoying and while the system still isn't perfectly silent its worlds better now.
    Last edited by jehu; 06-27-2011 at 02:23 PM.

  17. #67
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    Quote Originally Posted by Auk View Post
    Anyone using the Image Dynamics under dash mini horns?
    Mmmmmmm. Not in this thread, since this thread is all for keeping the same speaker configuration .

    I would start another thread of a custom setup

    I loved my image dynamics ! too bad the company went under
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  18. #68
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    Isn't 7 the "Gal" aka speed sensor?

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    Quote Originally Posted by attack eagle View Post
    Isn't 7 the "Gal" aka speed sensor?
    haven't seen a diagram of the CD43 pins yet..

    Whatever it is whtih a harness wire connected to it in my car I got a constant low level tikcing maybe soemthing like 120 bpm (beats per minute).

    Removed from the radio that is gone.. I have the speed/volume sensor set to 1 ( least adjustment) so if pulling wire seven loses it I am fine with that..

  20. #70
    Stereoinstaller1 is offline Senior Member Supporting Vendor
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    Quote Originally Posted by jehu View Post
    haven't seen a diagram of the CD43 pins yet..

    Whatever it is whtih a harness wire connected to it in my car I got a constant low level tikcing maybe soemthing like 120 bpm (beats per minute).

    Removed from the radio that is gone.. I have the speed/volume sensor set to 1 ( least adjustment) so if pulling wire seven loses it I am fine with that..
    That pin is the data bus wire on the E36 and newer. SSA and steering wheels, plus the vehicles databuss data is on there, this the ticking.

    A diode inline should fix it, or just cut the wire to use on your DICE box.


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    Some small progress today. I put the Lanzar crossover on the test bench and checked it out. The inputs begin to overload at about 3.2 Volts RMS. I checked this by feeding it a sine wave at 1000 Hz and turning up the voltage until the top of the signal began to get distorted when viewed on an oscilloscope. This is a decent match to the C33 max output voltage of 3.5 volts RMS. It should work well if the speaker level signal wires in the back of the car are soldered to RCA jacks. I still have not measured the output of my CD43 to see if its higher output voltage is going to be a problem.

    I also took some frequency response measurements of the filtered outputs of the Lanzar crossover. I have attached a jpg file showing the sub, midrange, and tweeter outputs. In this application, the sub outputs will be used to drive the amp channels for the kick panel mid-woofers. The filters were set at 240 Hz for the sub to mid crossover and 2500 Hz for the midrange to tweeter crossover. The frequency scale on the graph is screwed up because my LMS software is old and its file export does not work well. I had to save the plots as Adobe Illustrator files and then import them into another program to save as jpeg files. It should still get the idea across regarding what the active filters are supposed to do. There is a glitch in the high pass filter response around 10 KHz that I can't explain. It was repeatable so I think it is real. I doubt it will be audible but it detracts from what otherwise is smooth response. I will probably try measuring it with another piece of test equipment just to make sure it is not my LMS card acting up.

    Next up, I am going to measure a 2.5" mid from Peerless that may be an even better choice for our cars than the 2" one. It can play lower and should work better with the 240 Hz crossover frequency. The magnet does extend deeper than any of the other drivers and it may not fit without some surgery to the ventilation ducts under the mids. More to come...
    Attached Images Attached Images

  22. #72
    Stereoinstaller1 is offline Senior Member Supporting Vendor
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    a hot air gun and some patience can do wonders...


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    Don't know if this was mentioned already.

    But has anyone considered using the stock E46 amp it is a 10 channel amp with active crossover. http://www.bmwgm5.com/Stereo_Amp.htm

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    Quote Originally Posted by eightynine535 View Post
    Don't know if this was mentioned already.

    But has anyone considered using the stock E46 amp it is a 10 channel amp with active crossover. http://www.bmwgm5.com/Stereo_Amp.htm
    That link is very interesting. I can tell you from my measurements on the E34, BMW has used almost the same crossover points in the E46. There is a big gap in coverage between low-mid and mid-tweeter crossover frequencies. I am speculating that the reason was trouble with integrating the mixed output from the speakers in the crossover regions.

    This is going to happen any time you have a large distance separating speakers with respect to the size of the wavelength of the frequencies in the crossover filter range. For example, the wavelength of sound between 300 Hz and 1000 Hz varies from 3.75 feet at the low end to ~ 1 foot at 1000 Hz. If you are crossing over from a kick panel woofer to a dash mounted midrange in this frequency range, it will be impossible to get a smooth frequency response between 300-1000 Hz because the separation distance between the drivers is greater than or equal to the wavelength of sound in this range. It has to do with the time of arrival of the sound waves from each driver and how the sound waves combine in the crossover region. There are two common ways to minimize this problem. One follows the philosophy that what is missing, is not audible and most listeners will not notice the lack of response in the frequencies between the crossover points. This appears to be the BMW audio design philosophy from the E34 all the way to the E46.

    This same problem exists with the midrange to tweeter crossover. The distance between the dash location and the door sail panel is large compared to the wavelength of sound between 4000 Hz and 7000 Hz. BMW purposely designed the crossovers with a gap in coverage through this range to avoid dealing with getting the drivers to integrate well with no gap in frequency coverage.

    Another approach is to use very steep slope crossover filters to minimize the overlap between the drivers in the crossover range. Higher end car audio equipment tends to use 24 dB per octave Linkwitz-Riley crossover designs for this reason. The Lanzar crossover I am trying here only has 12 dB per octave slopes on its filter sections but it is a relative bargain at < $100 street price. It is not the best choice for high end sound but it should be a large improvement over the stock BMW design. I will have to experiment with leaving a gap between crossover frequencies with the Lanzer to see if it sounds better.

    In modern high end mobile audio systems, the problem of integrating driver response when the woofers, mids, and tweeters are not physically close together, is handled with Digital Signal Processors like the Zapco DSP6, Audio Control DQX, Rockford Fosgate 3SIXTY.3, JBL MS-8, and Bit One. These processors can time align the sound waves reaching your ears even if the distance between the speakers is large. The down side to this type of tuning is that the time alignment only works for the location the tuning microphone is located - usually the driver seat.

    One last point. The problem of integrating the output from drivers that are not mounted close to each other is also present in every component speaker system sold today. I don't care how expensive your speakers are, if they have a passive crossover, they suffer from this problem. I am sure the designers of these speakers do something with their crossover design to minimize the problem but it will never be as effective as steep slope active crossover filters with separate amp channels for each driver.

    Let me bring it back full circle to the original intent of this thread. Simple upgrades will never be able to address all the design issues involved in achieving high end sound in a car. The issue is what can we do as E34 owners to get a noticeable improvement without spending big bucks? It may turn out that following what the BMW did in leaving gaps between the crossover frequencies is the best bang for the buck.

    It may also turn out that installing a better mid in the dash and eliminating the sail mounted tweeter will sound better than keeping this a 3 way system. That topic is for later in this thread...

  25. #75
    Stereoinstaller1 is offline Senior Member Supporting Vendor
    Join Date
    Feb 2010
    Location
    Centralia, WA
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    My Cars
    All of them!
    Mark, here is a question for you: when you are done with your car and I am done with mine, can we meet somewhere in the middle of the country and compare SQ?

    I am glad to see we are both on the same page. Active is far superior, driver distance (and phase angle!) affects both slope and crossover points, but a properly designed (for the car, not a computer screen) crossover can still do just fine, especially considering cost.

    I would like you to install one of my crossovers when they are done. Not in your car, obviously, but do you think you can find a local who would want to go that route?

    I so want a "review" from you (a couple other guys are on this list too, worry not)!

    Luke


    Closing SOON!
    "LAST CHANCE FOR G.A.S." DEAL IS ON NOW


    Luke AT germanaudiospecialties DOT com or text 425-761-6450, or for quickest answers, call me at the shop 360-669-0398
    Thanks for 10 years of fun!

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