Hifi audio upgrade guide

Theruleslawyer · 12-03-2024, 02:34 PM

So you have a Hifi system, but want better sound? Let me show you how to do it the cheap and easy way DIY. A lot of this applies to the HK system as well, but the specific recommendations vary a bit since there are more channels. Thematically, its the same idea. I'll let someone else speak to the specific parts. This is for pre-LCi cars. I understand there are some setup difference that I hope people will chime in with.

Part 1- Upgrade priority
The hifi system has some okay speakers in it. The real failings of the system are a couple-
1. The amp is underpowered
2. The underseat sub design is just terrible. They are actually okish speakers, but the physical constraints of speaker excursion and enclosure volume mean this is a mid-bass driver at best, and when pushed to run low frequencies it runs out of power and excursion really quickly.

So what makes the most difference?
1. Match up 8DSP. You get an amp that has the power that the factory system really should have had. It's not going to win any SPL competitions, but it makes the stock speakers come alive and will power the mid range PnP upgrades just fine. More importantly is it gives you time alignment and serious EQ power to adjust for the complicated acoustics of a car interior. It seriously makes a huge difference

2. A real sub. That means a box in the back or under the sub floor in the trunk well. You don't need anything amazing, you just need to obey the laws of physics to make low frequencies. The stock subs can't effectively produce low enough notes at any volume. This allows you to retune the stock subs as mid-bass drivers where they are a lot more effective.

3. Midranges and tweeters. You'll gain a bit of clarity and detail here. If you want to save a bit of money, you can do just the front doors. They'll have the most impact on clarity and imaging.

4. Last is the underseat subs. Due to the laws of physics there isn't a lot to be gained here. There are replacements that offer a little bit more excursion, provided you have power, or could be a bit more clear. If you're looking for a thumping sub you won't get it out of an underseat upgrade.

Part 2- Specific recommendations
The stuff I'm going to recommend is based on value for an easy DIY type install. If you're looking for a SPL king, or high end audiophile experience you're going to need to go more custom. I'll tackle these in the order I recommend doing them.

Note: When using EU shops, always run all the way to checkout for a final price. Most have ~20% VAT included in the list price and are cheaper when the US is selected as the shipping zone. The shops I mention below are ones I've actually dealt with.

1. Audiotech Fischer Match Up 8DSP. Its the amp Bimmertech uses. There are other options out there but this is the easiest path. Yah, its expensive, but it also will make a huge difference to sound and is needed to integrate any other changes anyways. You should be aware that the stock amp has built in EQ and cross overs. This helps return that to a flat unified signal for any hardware changes. I reccomend buying this from 12voltshop its currently under $700 shipped. You'll also need a Match PP-BMW 1.7RAM harness cable for UP 8DSP amp. In addition you need about 4ft of 8gauge copper wire for both positive and negative, and a 50 amp inline fuse. You'll need 2 ring terminals as well. I bought battery cables on amazon that had ring terminals preinstalled. If you're uncomfortable with ordering directly, allwoods on ebay is a good, if more expensive, option.

2. Subwoofer. There are a ton of sub options out there. I think the best option is a low profile sub in the spare tire well under the floor of the cargo area. I got a JL audio 12tw3 preloaded in a box. I got a used one off ebay, so I won't link a store, but $400-500 seems typical. Any of the kicker 12" preloaded low profile subs would probably be fine, but the JL is regarded as one of the best low profile subs. Finding low profile boxes that fit to add your own sub is a PITA, so I think a preloaded low profile box is the best option for a cheap DIY approach. There is a custom box for 2 10" subs, but the box alone is $400. You can get a powered sub box, but I don't think they are a great value. They are slightly simpler to install, but limit options a lot. When looking for an amp you're looking for a monochannel amp that is 2ohm stable with an output in the 500-600w range. I just goto a major discounter and sort by % off and get whatever is closeout from a major brand. I ended up with an infinity 600w amp. In additional to the amp you'll probably need 4ft ea of 6Gauge copper wire for positive and negative. That varies a bit depending on mount location. You'll need a fuse around 70-80amp and two ring terminals. You may want a board to mount the amp etc to. Cheap commercial cutting boards are popular for audio installations. Any sub is way better than no sub. If that means the kicker rather than the JL, don't get too hung up on quality here.

3. Focal Inside speakersThere are a number of PnP style speakers. Bimmer tech, bav sound, focal, and I think a couple brands only available in germany I don't know much about. They are all mid range speakers. Sonic signature preference aside, Focal is a company that their primary business is high end speakers and I own home audio from them I was very happy with. That said focals are known to be very detailed speakers. That's a little much for some people's taste. You can tune it in EQ, but if you dislike detailed speakers, maybe try the others. The other big plus of Focals is it is possible to get them much cheaper than the others. I spent less than $400 shipped doing all the mids and tweeters. For a highfi system you need to buy three packages- Rear doors Focal F-ICBMW100, Front doors Focal ISBMW100L, and center channel Focal F-ICCBMW100 You need 1x each. If you're not comfortable ordering overseas they are on ebay at much lower prices than US retailers. Just be careful with part numbers as there are really similarly named parts. I can't vouch for bimmertech or bavsound, but people generally seem happy with them even if they are quite a bit more. I didn't need anything to install, but I'll cover the details when I get to the install section.

4. Under seat subs I'm sure this will be controversial with some people, but I honestly don't think you need to do this one if you do the above. The real sub will cover the frequencies these struggle with and allow the stock speakers to focus on the mid-bass where they don't bottom out. I'd get the focal isub bmw 2 There are a couple options out there. The Earthquake Sound SWS-8Xi is pretty popular. With the additional power from the 8dsp in 2ohm mode it models out as louder than the stock sub. The other options I'd consider more sound quality options than loudness options. Reports on the earthquake is that it has a big midbass hole that needs to be EQ'd out. Not a huge issue with the DSP, but a problem if you're trying these first. By the time you get here you don't need more punch from your mid-bass. The issue I have with the earthquake is that they aren't a ton cheaper than the focals I found. VS the sort of overpriced bimmertech and bavsound underseat subs they are a good deal. There isn't a lot needed other than tools to install these. I think the earthquakes require some adapters as they aren't a PnP speaker.

To be continued-
Part 3- Installing the gear
Part 4- Tuning using DSP PC-Tool for Match Up amps and RTA

Theruleslawyer · 12-03-2024, 02:34 PM

Part 3- Installing the gear

Again I'll be going in order of my recommendation for upgrades.

1. Installing a match up 8dsp

Parts needed
1x DSP
4ft positive 8 gauge copper wire
3ft negative 8 gauge copper wire
1x 50 amp inline fuse
2x ring terminals
Zipties
1x Match PP-BMW 1.7RAM harness cable
1x remote harness (included with dsp, optional)

Note on LCI cars- apparently some LCI cars require a resistor box if they have a specific package

Installing the DSP
Prep the back of the car. The DSP will be installed in the drivers side cubby in the cargo area.
1) Remove the drivers's side cubby cover and put it aside.
2) Lift the cargo cover.
3) You should see a plastic cover to the rear of the car. It is held down with pop rivets. Slide a small screwdriver into the notch on the side of the rivet and pop the center up. You can then pull it out by hand. When all of them are out the plastic cover should easily release and expose the battery. If you're having trouble, you missed a rivet.
4) Inside of the cubby, locate the stock ram amp. It's toward the upper right of the cubby door. Facing the rear of the car is a large connector with a lever style release. Refer to your match harness to see how this style of connector operates. With the release fully up it should pull out with minimal force.
5) The harness will install between the stock amp and the stock harness. The actual order doesn't matter a lot, but I found it easier to connect to the DSP last. You can push in and lock the connectors to the stock amp and stock harness the same way you undid the stock harness.
6) Prepare the power connections- The DSP comes with a small power block. Strip your wires and slide them into the power block and secure the screws. You may choose to use ferrules to protect the wires, but they are not strictly needed. Feed the wires under the plastic from the cubby to the battery. Slide the power block into the DSP until it clicks.
7) Connect the remote harness if you are going to be running a sub. There is a remote in and remote out wire. You want the remote out wire. You will need to extend this to your sub amp. It carries very little current so thin gauge wire is fine.
8) Connect the DSP to the harness. The connectors only go in one way. At this point you should have wiring from stock RAM AMP to DSP and back to the stock amp harness.
9) If you're running a sub, run your RCA wire under the plastic and to the tire well after connecting them to the single output on the DSP.
10) I stored the DSP in the foam at the bottom of the cubby. You will need to make a couple notches in the foam to make it fit, especially the wires to the harness, which I pointed to the outside of the car. It is a snug fit and has airspace under the DSP as well as above.
11) Power time. Negative ground is to the left of the battery. Use a socket on an extension to undo the nut and slide the negative wire with ring terminal on the bolt and reinstall the oem battery wire. Caution- its easy to lose the nut in the sheet metal to the left. Its handy to have a magnet on a stick to catch the nut as you undo it.
12) Positive requires the installation of a fuse. Cut the wire about 8" from the battery end. This should be approximately in the middle of the battery as you run the wire between the battery and tire well. Strip the ends of the power wire from the cut and install in an inline 50a fuse. Typically this is just a screw clamp. Again use ferrules if you care. On the positive terminal of the battery there is a accessory terminal you can use for the positive ring terminal. If you didn't buy a battery wire like I did you may need to crimp this on.
13) Zip tie the fuse down to the stock wiring running behind the battery. At this point you should have power from the battery to the DSP.

Don't be surprised if you can't play audio at this point. Likely you need to upload a tune to set the audio routing which I'll cover when I get to tuning. Its safer to not to attempt playing audio until you load a tune. I'll update this with more images and specific sockets in the future.

Another user modified the stock bracket to mount the DSP if you prefer- https://g05.bimmerpost.com/forums/sh...8&postcount=24

Here's the bimmertech video for a more visual explanation- As a DIYer we don't have their special bracket, but it shows the same basic steps.

Some people have used the OEM amp bracket BMW PN 65156832598 to mount amps in the past.

I'll update this post as I finish the rest of the install items
2) Subwoofer install
3) Door and dash speaker install
4) Underseat speaker install.

Theruleslawyer · 12-03-2024, 02:35 PM

Part 4: Tuning and RTA

Stage 1- The basics

Loading a base tune- This could be a file from the forum or a vendor. Rather than rehash it, Ill let Bimmertech explain. It'll get you up an running, but if you're not running all the same hardware the results will be suboptimal.

Tune library-
Assortment of tunes collected off the forum- https://g05.bimmerpost.com/forums/sh...66&postcount=9

Stage 2- Custom tuning
If you don't have the same speakers as a base tune or just want to learn more about how to modify a tune, start here.

DO NOT ATTEMPT TO PLAY AUDIO UNTIL YOU HAVE ELECTRICAL CROSSOVERS SET! THIS IS A BASIC SAFETY PRECAUTION TO PREVENT SIGNAL REACHING YOUR SPEAKERS THAT COULD DAMAGE THEM
*Unlikely with the PnP, especially at lower volumes, but don't get get done with routing and immediate see how loud you can blast your music.

Basic Steps-

1) Routing- This is the equivalent of hooking up wiring and making sure the right inputs go to the right outputs. We'll get to the details later.
2) Input correction- OEM radios have crossovers and EQ applied to the original signal to suit the OEM speakers. It would be best if you could get a clean full range signal, but with all the integration of systems you end up having to piece back together a full range signal
3) Electrical cross over- This is done virtually, but it define where the speaker is allowed to play. You don't want your tweeters trying to play sub frequencies for example.
4) Time alignment- This makes sure all the signals arrive at your head at the same time.
5) House curve- This is the acoustical target you are aiming to match. Think of it as the signature of a speaker. You could play flat, but a lot of people like elevated bass, etc.
6) EQ/RTA- This is the adjustment of the speaker's actual performance in the car to match the desired curve. Cars are a complex acoustical environment and EQ is the only way to get them to sound like they would in a room.

There are also a couple types of tune I'll touch on throughout this guide
1) Driver focused/single seat tune- Highly optimized sweet spot
2) Multi seat tunes/all around audio- Generally what you'd get from a factory
3) 'room' audio- Front stage focused with the rear designed to emulate a large auditorium

This is all for the match/helix series of DSP. They both use the same software. I'll be posting a few videos here related to helix, but know the same techniques apply to match.

To do a lot of this you'll need the ATF test tones. Click on the button when you start DSP PC TOOL and copy all the MP3 to a usb drive.

You can play these on the stereo as required.

You will need a MIC to get the most out of this process. I got the Dayton.
Dayton UMM-6
or
Mini DSP UMIK-1

1) Routing
So you have a couple decisions to make here. If you're starting with a base tune routing is going to be setup, but you might want to be aware of what went into it. Don't worry too much if things sound a little weird as you set this up. It all comes together in EQ.

Virtual or standard?
Standard routing is simpler, but disables some of the effect options on the DSP. I'd recommend virtual as it gives you more flexibility without a ton of added complexity. It allows effects and has an additional layer of EQ if you want to adjust summed channels before they go to speakers. Virtual routing enables the FX tab.

Signal Management
Your next step on a blank setup is generally the signal management. If you plan on using multiple inputs you may need to adjust this, but a basic install just check that Main input is set to 11.0Vrms (default) You could probe with a digital multi-meter, but you should end up here.

FX
Under augmented bass processing you'll mostly be interested in subXpander. It makes the sub sound lower than it can actually play through science. The trade off for me was that it sounded slightly fuzzier. Try it and see. It makes the under seat subs sound way deeper. Center processing is mainly about the real center. It'll enable your center channel as a virtual channel and center only content gets sent there. I like it, but some people don't. Clarity expander can help add detail to speakers if you're on the stock speakers. Most of these are best played with once you EQ.

Channel summing
The g05 does not have a full range signal available. You could simply say front right to front right, but then you are stuck with whatever crossover BMW thought was best. You get around this by summing channels. For example if you add Front Right to Right sub you get a full range channel. I like to reconstruct all the input to every speaker as a full range speaker, that way I have the power to make all decisions. For a G05 that means adding the sub to every door channel. Also add the mids to the sub channels. I used the fronts. This allows a higher crossover if you need it. Here's the detailed how to-

2) Input correction
This helps remove OEM EQ and cross over. I don't have a lot of comment other than follow these directions. Its not strictly required. The Hifi system doesn't have a ton of EQ or time alignment that needs fixed. However it gets you to a better base.

DLC
As a subset of input correction, you may notice that bass output varies with volume. This is done to protect the weak stock subs. If you notice this happening, here's how to fix it-

Here's the reference on it.
https://www.audiotec-fischer.de/en/k...p-pc-tool/dlc/

3) Electrical cross over
This assigns frequencies to each speaker to handle. Generally each pair should be the same. Each speaker type has a cross over type best suited to it. The goal is to have an electrical summation to a flat signal. That means cross over points should match and slopes should match. IE If I set my sub to lowpass 100hz -24db Linkwitz, my Mid should pick up high pass at 100hz -24db Linkwitz. Generally 2xFS is a good starting point, but with 4" mids you will really struggle to achieve that. The higher you push the subs the more localized they will be. You'll find when you start to EQ that you may need to revise these to get the performance you want. The EQ video will go into more detail on how they interact.

As a starting point I used -24db linkwitz cross overs
Stock Subs- Bandpass 50hz to 150hz. You need the low end filter to not make them bottom out when pushed. A subsonic filter allows you to push midbass harder.
Stock mids- Highpass 150hz

If you add a real sub-
Sub low pass 100hz
stock subs bandpass 100hz-200hz
mids highpass 200hz

Adjust to taste. The stock subs are better at midbass. I bump them up as high as I can tolerate for localization. This is all done in the outputs section of the tool. You don't need to touch the EQ here at this point. Just set the crossovers. Once you're done here it should be safe to play music.

If you really want to get deep in the weeds you can optimize the crossovers for a particular house curve. Here's a link to a spreadsheet that helps you do that.
https://www.diymobileaudio.com/threa...nd-rew.456458/

4) Time alignment
Use the included time alignment file and a mic to auto set your time alignment. Play the sound from the USB drive and follow along. Its almost magical the sound change. You can do an okay job with measuring, but the mic is more precise. If you're looking for more of a 2 seat tune, just measure from the center of the car rather than where your head is. I noticed a lot of the 'stock' tunes I found didn't include time alignment. Even if you are using a Bimmertech file, I'd suggest taking a look at this setting.

5) House curve
House curve is really part of the RTA process with tune EQ. What you are doing is specifying how you want your system to respond when you Tune EQ it. I call it out because it is a pretty important choice. I did the ATF curve which is nice, but there are a lot of house curves out there if you want to match the response of a specific manufacturer. If you want a bass heavy setup, this is the place to set a custom curve. Don't attempt to adjust the speaker EQ on the output page manually. Come to the custom house curve in tune EQ and set what you want and let the mic do its magic.

6) EQ/RTA
Only thing that wasn't super clear in the video is you don't want to touch the reference curve after you set it. Leave it alone and adjust the level on the speaker to get it close the the target. You absolutely need a mic for this step. If you have gone to the expense of getting a DSP and speakers and aren't using a canned package like Bimmertech you really need to spring for the mic. Tuning by ear takes 10x as long and isn't anywhere near as successful. Tune speakers individually, one at a time with only one speaker playing. I'd Start with the speaker furthest from you as it will be the quietest and you will be adjusting gains to match. In general it is better to adjust gains and EQ down rather than up. You can cut an unlimited amount of signal, but you have very limited headroom up without distortion.

dombi · 12-04-2024, 02:07 AM

Wow. You've put a lot of work into this.
Great writeup. Awesome!

Question: did you adjust Input Gains (in Advanced Gain Setup)?
Fronts / Rears / Sub... how did you do it?

Did you correct the Input signals from the stock system, using the Input Signal Analyzer (ISA)?
Do you have the stock measurements saved?

How did you do your input summing?
Front L + Sub L / Front R + Sub R... etc?

For the Sub in the trunk, I am using an active Sub from Audison.
It fits in the X5's tire well perfectly.
While it is not a 12" Sub, but it does come with a build in Amp, and it sounds amazing. I have it turned up only about 50% and it really gets the job done.
It plays down to 30Hz easily.

Link (if anyone is interested):
https://audison.com/product/apbx-10-as2/

Theruleslawyer · 12-04-2024, 10:21 AM

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