Where is the crossover located???

[sneekens]

6.5" for the mid bass, 4" for the dash speaker... Has anyone tried to customize this? i want my system to look discreet as possible... my tweeters seem to fit snugly.


thanks!

[cobb535]

It is built into the factory amp. The amp is located in the trunk on the left side,

[Paul in NZ]

I thinks its part of the amp lh side boot(trunk) looking into the trunk behingd the panels

[sneekens]

I thinks its part of the amp lh side boot(trunk) looking into the trunk behingd the panels


i just removed the cover now and the amp is now exposed but i didn't see any crossover... is there another place for it?

[Paul in NZ]

as far as I know thats where it is

[sneekens]

ok. thanks!!!:D

[attack eagle]

what year? 94-95 are different and do not use the big passive setup AFAIK.

this entire thing is the xover board. there is a vertical input output board, and on the opposite side (heatsink) the amp itself

http://i18.photobucket.com/albums/b106/AttackEagle/audio%20gear/100_1132.jpg

[sneekens]

topic changed....

[AngryPopTart]

what year? 94-95 are different and do not use the big passive setup AFAIK.

this entire thing is the xover board. there is a vertical input output board, and on the opposite side (heatsink) the amp itself

http://i18.photobucket.com/albums/b106/AttackEagle/audio%20gear/100_1132.jpg

Is this the same as the amp in the back of my '89 E34? If so, why don't I hear of people bypassing the crossover and adding aftermarket speakers with their own crossovers?

[AngryPopTart]

It is an amplifier, with a passive crossover inside meant for the speakers in the rear tray. I meant bypassing the crossover components, retaining the powered signal from the rear amplifier. The front deck does not power the rear speakers.

[attack eagle]

because you need an amp. And yes you do hear of people ditching the entire thing and starting over.

[attack eagle]

It is an amplifier, with a passive crossover inside meant for the speakers in the rear tray. I meant bypassing the crossover components, retaining the powered signal from the rear amplifier. The front deck does not power the rear speakers.
it doesn't power the fronts either. :D all 10 channels run of the little 4 channel amp.

so you'd have no amp at all, or you'd wind up with really low impedence after taking all the caps n coils out of the board.

[bmwrp8]

does all e34's have an factory amp.? like the 89 525?I didn't see any factory amp.before when I looked in the left rear

[timandbim]

...which in my '89 is embedded in the rear window, but i think most cars have a seperate antenna. i have read somewhere that there are actually 3 antennas in the window and a chip that chooses the best signal to route to the head! definitely not something i want to mess with!

maybe this thread (http://www.bimmer.info/forum/showthread.php?t=11484) will help you... it shows how to bypass the amp and keep the original crossovers. i'm planning on doing this... one day. in your case you could do a reverse approach (keep the amp section working, bypass the crosssovers) and end up with 4 powered full-spectrum outs (stereo front and back) ready for you to crossover any way you like.

[AngryPopTart]

I have an '89 525i and it has the amp in the left rear. It also has the tweeters on the doors, which from what I've read, some don't feel is very common, although every 525 I have ever seen had them... and our family owns 3. (My auto and my bro's manual, plus a manual parts car, all of which have the tweeters on the door. All 89's IIRC.)

I don't remember the rear amp powering the front channel. Can you confirm this? From what I remember, the deck powers the front channels and also sends a powered signal (high signal rather than line-level) to the rear amp, which from what I understood, only powered the rear channels. This is confusing, now, because I suppose there are enough inductors onboard the crossover in the rear to run all four corners. Actually, if that's true, I am very happy because I have been considering reworking the amp, but I felt it was a waste if it only powered the rears because then I would have to open up my deck again to see what it's crossover looked like. If it's all contained in the rear amp then I am now even MORE confused as to why people don't just remove the crossover and change to aftermarket speakers.

On that E34.net site, it says that changing the speakers doesn't do alot because the factory crossover keeps it in check for use with the factory speakers. Then FRICKIN GET THEM OUT OF THERE and then change the speakers. Most component speaker sets I see on the market all come with their own little crossover you have to wire up anyway. The amp in the back is just an assortment of opamps and crossover components. Bypass the crossover components and you have a raw powered signal like you would use in your home with your standup mains. There are crossovers in each main, and in the same way here you would have the crossover outside of the amp.

I hope you can confirm that the rear amp DOES power everything, because if that's the case I am going to recap the entire thing, ASAP! I was going through an extra amp last night and it would be nice to recap the big bipolars with film capacitors. The values are a simple thing to aquire, but they will obviously be much larger, physically, than the electrolytics which it has from the factory. The big 2200uF 16V power caps are also easily aquired in an ultra low impedance, high ripple fashion and you can easily get them them in the 20mm height, which is essentially the tallest you can possibly use in these amps. This would be great for improving bass performance and... oh gosh, I'm excited now.

Another good reason to recap the factory amp is because it contains alot of 85c caps, which I don't think is a great thing for a car, since it tends to get very hot. Often times, certain areas of an automobiles electronics contain caps specifically for vehicles, at a 125c or so rating, so 85c seems kind of misplaced. Those babies are probably falling out of spec very easily. In fact, since I want to install film caps in the crossover, and they are more sensitive to temperature, I think this is going to call for some modification to the case of the amp for better cooling. Perhaps even a fan install would be good. Gotta wait till a little cash comes in and I'll do a write up on this right away. Now, I wish I would have done a write up on fixing the volume knob on the deck. Oh well.


EDIT: Also, if the rear amp powers all four corners, then there must be a way to completely forget about the deck and run something like an iPod off the factory amp... unless the amp HAS to get a high signal... in which case, I don't know how you get around that. I'll check the datasheets on the internal amps, later.

[AngryPopTart]

I'm not interested in ditching the amplifier in my car. I am interested, however, in the possibility of changing the speakers out, but that would require my changing the crossover if I wanted it to be correct. At the moment, I'll just focus on improving the factory amplifier since it's something I can do, and I have an extra one sitting here. The factory setup gets plenty loud enough for my needs, but cleaning up the sound is desirable. Looks like this is going to be similar to my Sound Blaster 16 project; nobody felt that was worth it, but I was happy. :D I'll do a write-up, anyway. If anyone else wants to hop on this, please don't hold back on my account, just GO! DO IT! DIY all the way!

[AngryPopTart]

I fail to understand why you would want to power aftermarket speakers with 3-4w per driver... or about 7w RMS. If you want cleaner sound the speakers are not the first thing to change, it's the super weak amp section. Any modern aftermarket head has vastly more power and dynamics than that cruddy little thing.

Dynamics? THIS IS DIY!

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[attack eagle]

on 92 up, it runs all 10 speakers, and moroza (bf.c) bypassed the amp section just as i did on his common ground set up so he could power the xover section from his aftermarket deck. as to whether he has an 89 or 90 I don't remember, but AFAIK it is the same amp regardless of 89 or 90.

pretty sure al US spec e34s have the upgraded 10 speaker set up, and thus the mirror tweeters.


IF you really want to ditch the amp, then add your own aftermarket amp and aftermarket speakers:

The easiest way with a factory head is probably to simply add rca ends to the speaker leads coming from the head at the amp's location...
( they are common ground, just like an rca would be)
use the factory turn on lead (white) for the aftermarket amp.

then take the 10 speaker leads off the amp and reuse them for your new speakers after connecting them to the supplied x-overs.

There is no use in trying to power an aftermarket speaker with whatever pitiful wattage the head provides, after all, why would BMW add a pitiful 20wx4 PEAK (call it 7w RMS) amp to the x-over if the head had even that much power? Most component sets call for 40wRMS or more to play decently

[attack eagle]

I'm not interested in ditching the amplifier in my car. I am interested, however, in the possibility of changing the speakers out, but that would require my changing the crossover if I wanted it to be correct. At the moment, I'll just focus on improving the factory amplifier since it's something I can do, and I have an extra one sitting here. The factory setup gets plenty loud enough for my needs, but cleaning up the sound is desirable. Looks like this is going to be similar to my Sound Blaster 16 project; nobody felt that was worth it, but I was happy. :D I'll do a write-up, anyway. If anyone else wants to hop on this, please don't hold back on my account, just GO! DO IT! DIY all the way!

I fail to understand why you would want to power aftermarket speakers with 3-4w per driver... or about 7w RMS. just turn the volume knob down to about 1/2 or a 1/3 and you'd get the same result.(aftermarket speakers are typically less sensitive than the factory ones )

the nokias are decent at double or even 10x the power (had mine running off the aftermarket head's 17w rms and the were MUCH better and now at 80w rms they actually have impact). If you want cleaner sound the speakers are not the first thing to change, it's the super weak amp section. Any modern aftermarket head has vastly more power and dynamics than that cruddy little thing.