My new 135i

[demas]

While I have a bunch of other things going on now, got back to thinking about the audio upgrade and direction to take with my Base Stereo. Up to this point I was hell-bent on going the full Logic 7/Harman Kardon/Top-HiFi path but after looking into this more, it's not worth it.

Was looking at second hand L7 amps and the fact that there are like 4 different generations and even within the generations you'd have to track down one that is compatible with your VIN otherwise the MOST signal can't be read, you have to pray that you get an amp which isn't broken and has life left, then look for the right harnesses and connectors etc etc. Just a headache. I know you can buy new BMW amps or aftermarket DSP's and make it work but not willing to spend on that.

I consider myself an Audiophile (the sane type, not extreme) but I do like to hear the sound of the E82 with the windows rolled down and find myself listening to the Armed Forces Network AM radio station over my CD's sometimes. Having great sound isn't really top of my list these days and for long drives I'm normally taking the F10 which has a decent setup.


But - the Base Stereo is as you know, really, really not great. So, can I make it a bit better without breaking the bank? After more research, yes I think so.



I have this Pioneer powered sub that I used in my old E39 which surprisingly sounded great. When I got the F10, I didn't need it but never threw it away. It ended up in my closet for over 10 years and wanted to put it back to use when I got the 135. Then I realized it had the Base Stereo which had no amp and had to research what kind of monstrosity BMW did with the system before I attempted to integrate it. Got busy with other stuff and it got put off.

Downloaded the sub user manual the other day and it had the answer I was looking for. This thing accepts both Line level OR Speaker level signals. Hell yes! Now I just need to tap into speaker wires for the signal. But wait, BMW EQ'd the front and rear channels differently so which one to tap into? Need to figure that out.

Ideally, what I'm planning now is
(1) install HiFi or Top HiFi tweeters in the doors and connect them to the front mids. Lot of folks have had decent results with this 'mod'. I can't find any indication that there are Ohm concerns if driven off the mid-range. Tweeters have high pass filters on them and the mids should have an available slot to plug and play.
(2) disconnect under seat subs. The subs send the signal to the mids so need to look at how to keep the signal to the mids and just transfer the sub connection over to my Pioneer powered sub.
(3) leave the rears as is or maybe add tweeters there if a cut-out is available on the rear deck. Some of the E90 guys have done this. Given the way the rears are EQ'd though, it might not add any value to the sound.

Some Base Stereo folks have reported a marked improvement with just speakers being upgraded. I'm on the fence - unless you go the amp route, don't think the head unit signal is good enough to make use of better speakers. I think the underseat subs really pull the system down and if you had door tweeters for better high frequency clarity and better bottom end which isn't muddy, you could improve the system quite a bit.


Will it be equivalent to a $3000 system? No. Will it be better than the Base system? Man, almost anything will sound better than this.

[tracer bullet]

Random thoughts -

* An old sub should be checked around the cone to be sure it's in good shape and not disintegrating
* Some levels of stereo were actually flat signals, not EQ'd by the factory am or head unit, I'm not sure which but you could check into it (MusicarNW site once had some info, and they were also on the forums some as VP Electricity)
* The HK systems had 8" woofers under the seats, they are decent fillers between the 4" door speakers and a real sub. Something like 20-60 Hz for the sub, 60 - 150Hz for the 8" mids, and 150Hz up for the front and rear speakers is common.
* You might check the levels form your system and what the sub can take, some BMW systems are super high and people need LOC's (Line output converters), Audio Control amps tend to be able to handle it (much higher rating) but most other amps cannot

[demas]

All great points, thanks.

From what I find so far, it looks like the Pioneer Sub can take speaker-level inputs from 2.0 ~ 20v. While it's been years, I think I did use the speaker lines in the E39 which had the Hi-Fi option (not the Alpine but Blaupunkt IIRC). That setup was really nice - decent sound at moderate volume which is what I'm after.


I'm looking at LOC's now and thinking you're right, that might be the better way to go. I can get a great deal for an Audio Control LC1i - has a 40V roof on the speaker level inputs (safer) and ground isolation options. Additionally, switch settings where I may not need to wire up a remote/on line to the fuse box making installation simpler.

Re MusicNW - yes, there was an E90 audio guide I found and in it they show measurements on the EQ'd signals for the Base Stereo. Based on this, tapping into the front channel would be better for a sub amp.

What is strange is that when I put the fader all the way to the rear in my car, I can still hear/feel the underseat subs which I understood to be powered by the front channel. That was about a year ago so will have to anyway eventually pull out the seat and get to the connectors and see what's going on.

Also, another guy, Technic that used to post - has a website selling harnesses and the like - I don't see products anymore on the harness or the jumpers he used to sell for us E82 base stereo poor souls just a few months ago.


Anyway, pulling things together on what I need - I'll do it this time without putting it off.


I'll say it again, this forum is great with all the knowledge of folks although our cars are 'old' now. It's still exciting as it was in the early 2000's with the E39 crowd all experimenting and offering feedback to the community. Funny, soon as I got the F10, the forums were like nobody touching anything, trying new things and if you did - oh my god, your warranty etc etc etc... dead place. Glad to keep this one active.




Cheers

[Fishee]

BAVSound base upgrade systems may give you some insight into your system too...

https://www.bavsound.com/pages/bmw-byk

[demas]

Originally Posted by Fishee

BAVSound base upgrade systems may give you some insight into your system too...

https://www.bavsound.com/pages/bmw-byk

Thanks. Yeah, been through their stuff.

Great company/products/online videos but not what I’m after. They did help educate me on the base system limitations early on.

[Fishee]

Originally Posted by demas

Thanks. Yeah, been through their stuff.

Great company/products/online videos but not what I’m after. They did help educate me on the base system limitations early on.

Yeah, that's what I was thinking - help you baseline stuff to know what you can do with what you have.

[demas]

Going to break this up into phases as below. As I was preparing the steps, had a few questions for any who may know from working on the E82 audio system.

1) First of all, connect and check that the powered sub still works. To do this, I'll need to access the under-seat stock 'subs'. I've read in old posts circa 2015 that these are glued in on the Base system (not glued for hi-fi or HK system).

Wondering if I could access the wiring plug without tearing the original sub out?

Also, if I leave the seat harness connected and just unbolt/rock the seat back - any issues with the aribag light triggering if I keep my battery connected?

The connector pictured below courtesy of ECS I believe is what is connected to the sub. Should be 4 wires from head unit - 2 for the sub and the other 2 trace back to the front mids. If disconnected from sub, signal won't travel to the front mids unless it's jumped. Technic PNP used to have a jumper for their 2/6(?) harness - none of which I see on the site anymore. Not surprised as that was years ago. I'll likely fabricate something.

If the Pioneer subs fire up, check on how it performs using the OEM sub signal to hear how it is.


2) While an LOC won't fix a processed signal, keen to try it through the LC1i to see if there is any improvement. I like the additional features it offers and in the worst case if it makes no change, it gives me a slight upgrade path as I would have a line out to a future amp.

3) Source OEM tweeters from either Hi-fi or HK. If decent, I might just call it a day.


Came across this thread as well which was interesting and aligned with my view that the underseat subs were designed as a mid-bass.


Least I can do is take them out of the equation and see what happens. The Pioneer has a frequency dial which I can play with. I also prefer a V shaped sound anyway.


Also, took a look at the fuse box for the first time. They weren't kidding it's all the way in there deep. I'll likely tap the cig lighter fuse #8 for the remote turn on.



Cheers

[demas]

Had a few hours today so did what I can before rain set in.

Added a fuse tap to slot #8 for the remote wire. Remote wire end needed a solder and plug for the connection. Will be ready to go when I need it.

Unbolted the passenger seat and accessed the under seat subs. After removing the grille, was able to access the connector - which was indeed 4 wires. It matched up with E82 wiring diagrams I found online. Also did a multi-meter test to check polarity.

Fabricated a crude jumper and was able to get sound to the mid's in the door without the subwoofer by connecting wire 1 with 2 and 3 with 4. Just then, rain set in so called it a day.



I'm going to make a jumper with a T-connector that I can route over to my Pioneer amp. That way I don't have to cut into anything right now. This is for a temporary test to see if I like the direction it's going in and whether the subs actually work..


Rain foretasted for the next 10 days - crazy we just hit the rainy season.

[demas]

Got it temporarily wired up - and the Pioneer Subs work... yay.

Last night I fabricated these jumpers from leftover guitar parts - I cut segments from spare potentiometer tabs I had in an unopened package - they fit perfectly snug in the connector.

Went to remove the drivers seat to do that side and I broke my T50. The passenger side was fine, the drivers side seat bolts did not budge. Ended up just pulling the carpet and was able to pull the connector out and wire.


Initial impressions:

1) Bass quality is much, much better but,
2) a good chunk of mid-bass is missing (expected) - somewhat correctable with dialing in a higher sub frequency
3) The front mid range speakers are crap - really noticeable when you hear them just on their own - somewhat tolerable though with Treble at -3 or so.
4) No tweeters yet - still shopping.

One thing strange is that while the front channels were tapped for signal, I still get sound out of the Pioneer sub when the fader is set to rear only. It was that way before as well where the subs worked when faded to rear only. Everything I've read on the Base Stereo was that the subs shared the Front channels.



It's all a work in progress - looking forward to adding tweeters and trying to get the best tune out of it.

[demas]

Slowly narrowing down the audio journey. Had a bunch of stuff come up including one of my tenants moving out so just finished getting the house prepped up and on the market. A third of the work I did myself like sanding and staining the back-yard deck in this summer heat.

Got the Harman Kardon tweeter grilles on the way from Schmiedmann. HK tweeters being sourced separately.

The reality is even with tweeters once in and the powered sub in the trunk, the mids are just too bad sonically. I've read almost every forum thread on the base system - a couple folks swear improvement with just L7 speakers but only to be blasted by other 'experts' about Ohm mis-matching etc etc. End of the day, good entertainment and you learn alot on various paths people take to address BMW's horrific marketing decision on the Base system (almost as bad as the Neue Klasse they are doing now :-)

I came across a few interesting products - the last of which I'm leaning towards.

1- VIBE Amp from the UK. 4-channel with plug and play harness. Nice but won't fit what I'm doing as I need 6 channels as I still want to keep the rear speakers. I believe it can accept low-level inputs post Hi-Fi head unit coding, but not sure.

2- A no-name Chinese DSP amp being sold on Amazon Japan. 4-channel amp but has RCA outs for a subwoofer. Could marry up nicely with my config. BMW harness sold separately for the -1-series'. Apparently for both E and F series but not entirely clear so I'm a bit skeptical. Also you need a Windows laptop to program the DSP which I don't have - and I won't ever have anything Windows.

3- Crunch CRE400. DSP amp from Germany. 4-channel amp with 6 RCA line outs. Can be a 4-channel amp with DSP or just a standalone DSP with additional amps for future expansion so it's a better proposition for not too much more cash. Uses AKM DAC chips - which I love - I use AKM chips for my home system specifically for their smooth sound. They offer an iOS app for DSP programming - perfect. Currently going back and forth with a tech in Europe on specifics like whether hi-fi coding the head-unit would work with this system.

I'd prefer to flatten the signal prior to DSP but have read in another post somwhere where a guy had better results DSPing the EQ'd signal and leaving it high-level. Of course everyone had their critiques which went on and on....



More to come but I'm enjoying the research and various options so not in a hurry. Additionally, got to get the F10 diff bushings changed out, the shift boot installed for the E82 and an upcoming vehicle inspection for the MINI.