[simicz]

Hi guys,

I'm new to this forum, have been a reader for long time, always when I needed something :-) But finally I decided to register as well, as this forum has helped me a lot and maybe I can also help pass the info further to other newcomers.

There are plenty of threads with great audio upgrades, usually based on the hifi audio systems. There are not so many threads for people lucky enough to have just the base stereo (no tweeters in A pillars, no amp), although there have been a few - and a few very good ones - especially this older thread by davethefish was of great help to me: http://f30.bimmerpost.com/forums/sho...d.php?t=997859

I recommend checking it out, maybe even before reading on here...

There have been a few things Dave did not mention, or that were not clear to me (more probable), and also a few surprises, so I decided to try to do a "revision", adding some of the additional info I gathered by not only reading all the threads, but also upgrading the stereo by myself last week. Some of these notes may help others as well. And as I also went a bit different way, this can be seen as another upgrade option.

None of this information is anything new, all of this can be found probably many times in many threads here or elsewhere, so this is more of a summary thread, I tried to collect all the information, and will try to present it in a way that goes along the installation - heavy on text, not so much on pictures :-( , but I'll try to add some I have taken.
Important to mention: credit goes to those who have done the hard work before me... mainly to Technics, who is constantly providing plenty of information to anybody who asks. Probably a good half of all this info comes from him alone :-) But it's for sure not only him...

Please, feel free to correct me if I am wrong on any of the points, any suggestions / ideas are more than welcome.

And check Dave's thread for all the pictures and tips on how to remove the trim etc. My comments below are more like supplementary to his original thread.

[simicz]

Base stereo specification to start with
(to understand what’s there and what needs to be changed):

- integrated amp in the HU, 4 channels, 6 speakers, power approx. 4x25w

- according to BMW should be 2 Ohm stable! (or at least was in case of older CIC head units - could not find this information for the NBT - can someone confirm? But I guess it will be the same, also because how (exactly same way) the front speakers are connected)

- 2 bass speakers under the front seats, 2 small speakers in the door

- door speakers are connected in parallel to the bass speakers, both are 4 Ohm speakers, so they create an impedance of 2 Ohm to the HU!

- probably to minimize risks (or because the HU is not really 2 Ohm stable), there is some capacitor mounted directly to the door speaker - could be dangerous to the HU, if you replace these door speakers (which means you remove the capacitor) with some regular 4 Ohm speakers while keeping them connected in parallel to the under seats bass speakers - that would result in full 2 Ohm impedance which the HU does not have to be safely capable of (adding an amp means you can feed the doors with a separate channel, and the bass speakers with another - so each channel will be loaded by 4 Ohm)

- additional 2 small speakers in the back

- front speakers signal is equalized to enhance trebles (to compensate for lack of tweeters in A pillars) - you can not simply de-equalize this on the HU

- rear speakers signal is a really sad one, lacking bass completely - do not ever try to connect a sub (or anything else) to this rear speakers (won't play, as there are almost no bass frequencies going to these speakers)

- front speaker cable is going to the under seat bass speaker, to a wide 4-cable connector, where it feeds the bass speaker (the thick wires) and at the same time goes out of this connector, and further to the door (the thinner wires) - so this wide connector is basically also a jumper (therefore, when installing Technics harnesses, where the signal to the under seat speaker goes separated, you have to use a jumper plugged into this connector, to ensure the signal goes through to the door and does not end in the connector).

- so this connector has actually 2 set of wires - there are cables bringing input to the bass speakers, and at the same time the thinner wires with output going to the door speakers - so if you unplug this connector and inside of it just connect the thick wires with the thin wires, you will bridge the input to the output and the door speakers will work

I would recommend to start with an amp installation first - this alone could be more than enough for many people - I was really surprised how well the original speakers can sound after feeding them with an amp. Plus for those who would not be satisfied by the amp only - once you finish this stage 1 update, you'll have the amp in place - upgrading the speakers in a stage 2 should be a fast job to do...

[simicz]

Main upgrade options:

Option 1: "2 to 4" (2 channel input to 4 channel output)
(I would probably not consider this option if I would not get a useful hint by Technics on this one… so thanks a lot!)

- adding a 4 channel amp to the trunk (best on the original place), fed with high level input from the HU (grabbed from the under seat speakers)

- the amp will be feeding the doors on separate channel and the under seat bass speakers with another channel

- rear speakers can be left connected to the HU (they are there anyway only for the space/fill effect, music in the end is stereo only)

- either the 2/4 harness from Technics can be used, or you can create your own one if, like me, you can not get it shipped easily - I'll list the part numbers later, just a small comment here - if your main motivation to create your own harness is to save some money compared to buying it from Technics - don't do that, Technics' harness is very good value for money alone those two counterpart connectors for connecting the cables to the under seat bass connectors will cost you almost 50 USD (at least here in Europe, when ordered directly from BMW)

- one speaker cable will be going from the front under seat bass speakers to the future amp location (on both sides of the car) - this one will be bringing the input signal to the amp
- 2 more speaker cables will be going the same route (on each side of the car) - these will be the speaker cables, so while the first cable will bring input sound from the HU to the amp, in these two the sound will go the other direction 😃 one will be used to feed the under seat bass speakers, the second to feed the doors
- so on each side of the car there will be 3 cables (each with a + and + wire) going from the under seat bass speaker to the amp position

- a 4 channel amp with High level input is needed (best one with auto sense, so it would switch on when it senses input - so you do not have to lead any wire for the remote power on)
- the amp will get a 2 channel input (stereo), and will output 4 channels - 1st channel for the left door speaker, 2nd channel for the right door speaker, 3rd for the left under seat bass speaker and 4th for the right under seat bass speaker
- splitting the under seat bass speaker from the doors and putting each on it's separate channel will also let you adjust not only the crossovers, but also gains - so if you prefer stronger bass, you can select a higher gain for the channels feeding the bass speakers - this alone does a big deal

- the amp will be amplifying the (rather heavily) adjusted front speaker signal, which has highly enhanced treble - so if you are about to replace the front speakers with some with a tweeter, you'll need to get a pair of speakers that allows you to lower the signal going to the tweeter - e.g. the MB Quart QM200.3 - the crossover of these speakers let's you connect the tweeter to either a 0db output (for stronger sound) a -3db for standard and a -6db for a silenced output (again thanks Technics for this hint and tip)

- alternatively if you want to use some other set of speakers, you could just pick a crossover that would allow you to set the tweeter to a lower output. Or, as crossovers are usually part of the speaker sets, you could use something like the Excursion XLR 6, which is basically a "silencer" (sorry audio pros, not sure how to call these parts) - they are relatively cheap and you can choose if you want a -2db, -4db, -6db or even -8 and -10.

- another alternative option would be to go with either an amp that has a DSP processor builtin, or with a combo of a standalone DSP processor + an amp - but as for the price of such a setup, it's already reaching the levels of the next "4 to 6" option, which I would prefer in such a case.

[simicz]

Option 2: "4 to 6" (4 channel input to 6 channel output)
(this would basically be a very similar setup to the original BMW “hifi”)

- if you want to preserve the rear channels as well, you have to make them full ranged first - there is no way a DSP could make these rear channels full ranged, as the bass signal to them is already cut of

- the only (and also easiest) option to go full ranged on all 4 channels is to code your NBT to hifi output - that will turn the output of the HU to low level, balanced differential signals - be careful to pick an amp that can accept these signals (and good luck finding this feature in the description, as most of the eshops do not list it)

- 4/6 harness from Technics would be your best way to go as for wires

- in this case, you'd better go with a 6 channel amp already - 2 channels for the front doors, 2 for the front under seat bass speakers and 2 for the rear speakers

- you do not need any DSP on your amp, as the signal after recoding to "hifi" is flat (and clean)

......

It's up to everybody to pick the way to go according to everybody's preference, taste and last but not least the budget :-)
I chose to go the easiest route - the "2 to 4" option described as first. I decided to not go with a DSP equipped amp and try my luck with those "silencers", as nice amps with DSPs are rather expensive. Should I already go with an amp of that value, I would pick something like the Match PP 82 DSP - and would go the "4 to 6" option already - for that value, I'd already like to amplify the hell out of each of the channels in the car

Compared to the probably nicer 4 to 6 option, the 2 to 4 option's biggest drawback is that you are amplifying an already modified output - on the other hand, it's the by far most cost efficient solution. I wanted to avoid using high-level outputs (am old school here so I just do not consider this a clean solution), but it turned out one does not have to be that sensitive here...
I was really surprised how well it works and sounds - I consider myself a hifi fan, someone who can appreciate a good sound, as for car audio, I prefer to drive the bass a bit more (compared to what would be natural recording representation) and in no way am I a true audiophile - so if you are one, ignore all my ratings here :-)

I picked a 4x75w Gladen FD75c4 and after installing the amp alone, still running the OEM speakers, I was so well surprised by the improvement, that I will postpone the upgrade of the speakers for now - I will probably do it at some point later on, just for the sake of the feeling - but hey, why all at once, like this, I can have Christmas twice

[simicz]

Some installation tips:

- don't even think of starting without having a good trim removal set - really! I did not get them, thought I would make it somehow... and got saved by my neighbor who luckily had a good set - I soon realised how hard it would be without them - after first few seconds I already knew It would be a nightmare without the kit

- for the speaker cables pick some reasonable thickness - I ordered 2,5mm gladen cables (thought it said square, but it was probably in diameter or I don’t understand how these are labeled) - they were so thick I could do some serious welding with them - 1,5mm should be more than enough and will be easier to work with - for the cables that will bring signal to the amp, you could easily go with something even smaller, most probably even 0.75 as that would get closer to what BMW is using for speaker cables - having the “input” cable in a thinner diameter would also make it easier for you to recognize it out of the 3



- don’t forget you are passing high level input to the amp, so your “input” cable should not be too thin - at one point I thought I would use some rca cable I had from my previous car, so I would not have to solder the cinch / rca connectors for the input cable at the amp - this cable had really nice massive rca connectors, so I cut about 20 cm of this cable, wanted to connect it to my speaker cables, just to figure out, that the copper wires inside that rca cable were thin as hair - probably good enough for transmitting low level inputs from HU to amp, but I definitely did not want to degrade my connection that badly



- for the drivers side (LHD car) I needed about 3,5 meters for each cable, for the passenger side about 4,2 meters (so a total of 23 meters - better order 25, you won't have to be that precise when cutting :-)

- if you (like me) will create all the cables from 1 type (color), figure out a way how to mark what is each cable for - I had isolation tapes of different colors, so I have marked the cables bringing signal to the amp with a white one (I wrapped the cable some 10cm from each of it's ends, so the color label stays even after splitting the ends) etc, for the drivers side cables, I labeled the cables twice, like two rings :-) But you can figure out a way for yourself

- it was actually pretty easy to fit the cables under the trim (once the trim was removed), there is some really thick padding - although it's not always easy to pull it off so you can get your whole hand down there... best try to push the cables under the original loom going on each side

- you need to lift the front seats to access the woofers - I removed first the back bolts, moved the seat all the way to the back and removed front bolts - like this you can easily tilt the seat back, without the need to disconnect the airbag cables (but better check how far it's tilting)

- the connector on the bass speakers is to be found on the “outside” near the rocker panels, almost like under the seat rail. It can probably not be accessed without lifting the seat. Once you unplug it, you can reposition it directly to the rocker panels under the padding - you will not be connecting it back to the speaker

- to avoid cutting any wires, a counterpart connector to the one you will unplug from the under seat bass speaker can be purchased (part number 61132360044 - all also listed at the end of the post) - this counterpart connector will be fitted with 2 of the cables you prepared before. Outer pins (1 and 4) will be used to connect the cable that is bringing the door signal (check the colors of the original wires, they are different on each side of the car, blue&red for +, blue&brown for - on the passanger side, on the drivers (LHD) side they were black&red and black&brown) the inner pins 2 and 3 will be used to connect the cable that will be going to the amp.



- I have folding rear seats, so unlike in davethefish's case, there was no need to unscrew anything - the seat itself can be just lifted up (but be careful with the seat belts buckets, they have to be pulled through the holes - and good luck pushing them back once you are done with everything)
- also the sides of the back of the seat (those parts covering the wheel arches) can be just pulled - grab it by the top and pull forwards, don't pull on the bottom, as there it sits in a metal bracket and has to be lifted up - so first pull out on the top to make it free and then pull the whole thing up

- under the back seat, it seemed best to me to lead the cables along the others going on the wheel arch under the trim - this will lead all these cables to the top of the wheel arch and get you to the trunk. It means leading the speaker cables along some juice cables, but I have not run into any issues with interference - and it was so tempting to use the nice black “tunnel” on the passenger side



- in the trunk, going from the top of the arch, on each side you can find a plastic tunnel (black on the left side, white on the right), that you can use to lead cables to the trunk floor - from there on it's already easy to hide the cables under the trim and lead them to the amp place



- don't rely on connecting the amp to the nice red distribution box that is fitted on the right on the arch above the battery - I have ordered the lovely 61136920094 connector and the plastic cover for it 61136925176 - glad I will have a nice and professionally looking connection - just to figure out later on, that my amp is not powered - and after a bit of searching, have found out, that the empty slots on this distribution box (is also used as fuse box) are not fitted with anything :-( so had to connect the cable directly to one of the bolts on the batter plus



as you can see, the empty slots are not populated with fuses at all:


this is how it would look like, if you'd have the full distribution block There are 2 types, the one without the additional slots populated and one that has them full (depends on vehicle specification) the full populated block is part number 61149225022



- The ground for the amp can be fitted right to the terminal that is on the wheel arch just above the area for the amp

- I fixed the amp to the car in a very similar way to what davethefish did in his thread (check installation, day one): http://f30.bimmerpost.com/forums/sho...d.php?t=997859



- try to fix the amp as close to the wheel arch as possible and as close to the center of the car as you can - I first fixed it nicely in the middle of the whole area, to figure out once I had the trim back, that the hole in the trim (under the cover) is not big enough to give me access to the amp’s settings - so had to take the trim out again and reposition the amp



- in the front, I left the cables long enough to reach approx to the front of the seat rails - once you reposition the big speaker connector to the rocker panel, under the padding, you’ll see it has good wire length, so it almost reaches the b-pillar, the longest end will be needed for the under seat speaker cable - it has to reach the connector on the speaker

- this third cable going to the under seat bass speakers can be connected directly to the connectors on the speakers (you can order another set of connectors if you want to plug into the original socket on the speaker - but if you plan to upgrade the bass speakers as well, you can save some money and use some smaller regular faston connectors and plug them directly to the pins in the connector on the speaker - it does not have to go to the inner pins of the connector (the are rather close to each other) - you can connect them also to the outer pins of that connector - that will give you more comfort when pushing them in

- at the end I used a plastic cable organizer (or how these are called) to cover the speaker cables going across the trunk

- one final "tip" - you can easily split the amount of work into several days... on the first day, I removed all the trim in the trunk (and of course in the car) and prepared all the cables and have led them to the trunk. I just connected them all together there - so I basically just created a loop. I used some wago spring level connectors for this temporary connection, and have connected for each side all the plus cables and all the minus cables together. I could cover back everything except the trunk. On day 2 I installed the amp and have connected all the cables.

The total cost of this first stage was maybe 100 USD + the amp, all together under 400 USD and the upgrade is already massive in sound difference.

Also good to notice is, that in case you'd need to sell the car in near future, in this case it is really easy to just unplug the amp and reconnect all the cables together at the back, and the system will turn back to original base stereo

[simicz]

Parts list:

- counterpart for the under seat bass speaker connector: 61132360044 - no need to order pins, as they come with the connector - at least in my case, where I even got 2 plates each with 5 pins in 2 different sizes - so 4 plates (20 pins) in total (at least something for that price - they are about 25 usd each) - you will need 2 of them

- counterparts for the door speaker connectors - only needed if you are replacing speakers as well, and if you do not want to cut any wires, order 2 of these: 61138373583, plus 4 pins (2 for each connector) 61131393723

- if you are not upgrading your speakers (or at least not the under seat bass speakers) you can order the connector 61132359996, pins should come with it, this will allow you to connect the bass cable directly to the original connector on the speaker, instead of the uglier faston connectors

- if you are lucky and have a spare populated slot on the distribution box, order either 61136920092 (for 2,5-4mm cable) or 61136920094 (for thicker 6-10mm2 cables) and the plastic cover 61136925176 - but doublecheck, I had 3 spare slots, but none of them was populated

- if you want to go the extra mile and have only the less-populater distribution box, you can order the full one and replace it: part number: 61149225022

- you'll have to remove your deep tray on the left trim (as there will be an amp under it), you can replace it with this shallow cover: 51477245912

- plus, if you are about to update the speakers as well, order the door frames of your choice: 51337323507 & 51337323508 for the non-branded ones, there are also some with the Harman Kardon logo.

- 22-25 meters of 1,5mm speaker cable

- 2 rca connectors (to connect on the input cables at the amp)

[Billfitz]

Originally Posted by simicz

- door speakers are connected in parallel to the bass speakers, both are 4 Ohm speakers, so they create an impedance of [B]2 Ohm to the HU!
.

That's possible, but not likely. If they run off the same amp channel there should be some sort of passive crossover components. At the very least there should be a capacitor in series with the door speakers, which would reduce the passage of low frequencies to those speakers. If there weren't the cones would literally try to jump out of the driver frames. There also should be an inductor in series with the under seat speakers, to divert higher frequencies that they can reproduce away from them. That frequency division would keep the total load at 4 ohms. But that's if they really are parallel.

If the integrated head amp is 4x25w the logical wiring scheme would be for two channels to drive the under seat speakers, two to drive the four midrange speakers. That would make the load on the amps for the midrange speakers 2 ohms. It's logical because that gives 25w to each woofer, and that's where power requirements are greatest.

This is purely conjecture, without seeing a system schematic one can't be sure. I've looked about but haven't found a schematic anywhere.

[simicz]

They indeed are connected in parallel. Front channel feeds the woofers and the door speakers, although there is a capacitor on the door speaker. Rear channels go to the rear speakers only.

It can not be 1 channel for front and back - fader would not work in such a case.

Exactly for this reason I believe it could be dangerous to the HU to just replace the door speakers (and add tweeters) to the default base stereo system...

[Billfitz]

Originally Posted by simicz

They indeed are connected in parallel. Front channel feeds the woofers and the door speakers, although there is a capacitor on the door speaker. Rear channels go to the rear speakers only.

If that's the case the load is 2 ohms only above the cap knee frequency, and not for much of a band width, as the inductance of the woofer voice coil will cause the woofer impedance to start rising around 500Hz or so. A cap alone is marginal, but better than nothing. A significant improvement would be made if there was a real crossover between the woofer and midrange.

It can not be 1 channel for front and back - fader would not work in such a case.

That depends on the fader configuration. With only 25 watts a rheostat isn't out of the question, but as the control is electronic you're probably right.

Exactly for this reason I believe it could be dangerous to the HU to just replace the door speakers (and add tweeters) to the default base stereo system...

Not at all, but the use of real crossovers is mandatory. I have the Hi-Fi, and as far as I know there's no true crossover between the midrange and tweeter, just a high pass cap on the tweeter. At some point I'll open it up and if that's the case I'll fix it. The same for the crossover between the woofers and midranges, if it turns out that they share the same amp.

[simicz]

Originally Posted by Billfitz

Not at all, but the use of real crossovers is mandatory.

Yes... and probably even more than just a crossover would be needed to have it safe...

If someone on a base stereo would just open the door trims and replace the original speaker with some set with tweeters, it would mean he'd be running 3 speakers on 1 channel! I haven't opened the door trims myself yet, so confirmation by someone with more experience would be good - but I am afraid that where the original speakers are somehow protecting/-ed, replacing them with anything non-OEM would mean loosing that protection and putting the head unit in danger (in case of the base stereo system). Correct me, if I'm wrong...
Therefore I'd recommend to first add the amp, split the channels to doors and under the seats, then proceed to updating the speakers first.

The HiFi system has already the bass speakers on a separate channel and the doors on another.

[simicz]

This document describes the Hi-Fi and Top Hi-Fi systems. It even includes diagrams. Unfortunately, as it is U.S. based, it does not describe the Base Stereo system at all

http://www.bimmerpost.com/goodiesfor...unication1.pdf

and this is from an older training document for the E series - can't find the european version of the F series document, but I guess the base stereo system will be very similar to the E series setup.

[Kevin @ Integral Audio]

simicz is correct on the wiring - the front underseat woofer and door midrange are indeed connected in parallel. There is only the cap on the door midrange, and none on the rear midrange. The rest is all eq coming from the headunit.

Lest anyone doubt the need to recode to HIFI, this is what the [B]electrical[B] signal coming out of the headunit looks like in the 6-speaker Base audio-equipped vehicles.

This is an F80, but all F3x/F8x similar. Blue= Front underseat + front Midrange, Orange=rear midrange.

View post on imgur.com

[Billfitz]

Having just a cap is crap. It provides only marginal protection for the driver it's used with, and gives mediocre overall results. That probably accounts for most of the complaints about the sound. This explains how crossovers should be implemented:
http://www.bcae1.com/xoorder.htm

[pedelgax]

Thanks for your post!!
I have a question, I will use a different amplifier, so I think we need to use signal connection (I see you do not use this connection). Where I take from?

[Billfitz]

With the base system you can use an amp that has speaker level inputs, disconnecting the wires from the head unit to the speakers, using them as the input sources to the amp. Make sure you don't connect them to line level inputs, that would blow them. Speaker level inputs usually are screw terminals, line level usually are RCA connectors.

[fakemail]

Hi guys.

I need help. I think I'm going insane.

So I'm trying to install an aftermarket amp. My car is equipped with the ASD unit in the trunk.

My amp is a top spec Sony XM-GS6DSP amp. It has an integrated DSP.

My question is, are the wires from the head unit to the ASD two way? Meaning does the head unit transmit audio to the ASD and then the amplified ASD sound go to the speakers?
If this is the case, can I connect the input wires to the ASD to the amps input, and the output wires the the amps output?

If this is the case, what wires correspond to the input and what wires correspond to the output.

I have attached pictures of the ASD cable harness showing the wiring.

I hope this makes sense.

If I'm being stupid, please can somebody explain how the wiring process with an ASD equipped car works.

Many thanks to whoever replies.

[JP1989]

Hi everybody,

I've had my base stereo updated to a Audio Fischers Match 8-channel DSP setup, speakers and all.

Referencing this line from the OPs post:

Front speakers signal is equalized to enhance trebles. One does not simply de-equalize this on the HU...

Does "simply" refer to doing any changes in the iDrive menu, or is this not doable using Bimmercode or other coding software?

I would like to code it so the DSP gets a flat input from the HU, before equalizing again, now that the speakers have settled.

Thanks bud

[Encanto]

Fix the boost with the DSP. That’s what is for...

Originally Posted by JP1989

Hi everybody,

I've had my base stereo updated to a Audio Fischers Match 8-channel DSP setup, speakers and all.

Referencing this line from the OPs post:



Does "simply" refer to doing any changes in the iDrive menu, or is this not doable using Bimmercode or other coding software?

I would like to code it so the DSP gets a flat input from the HU, before equalizing again, now that the speakers have settled.

Thanks bud

[JP1989]

Would it not be better for the DSP to get a flat input? According to OP the rear speakers get little to none low frequency sound.

I assumed that this would be possible, as the HiFi system uses an external amplifier, which then does the EQ, or does it get the same input as the base system?

[Billfitz]

Originally Posted by JP1989

According to OP the rear speakers get little to none low frequency sound.

They're not supposed to. They can't handle low frequencies, so they aren't sent any. The front door speakers don't receive a full dose of lows either, filtering them out is the purpose of the capacitors between them and the woofers.

[VladiArsenal]

Hi, I was wondering if anybody has any feedback on replacing the stock speakers that come with the base stereo option, without adding an amplifier. I am sort of satisfied with the overall power of the sound, but I wish there was more base to it and was thinking if just replacing the underseat woofers will improve the depth and punch of the base?

[Billfitz]

That depends on your location. SF isn't exactly specific. If you have a US car you don't have the base stereo system, you have at minimum the hi-fi system.