'89 Convertible Sound System Help

[MaCheFai]

MaCheFai, these are two-way speakers. Since you utilized these in the front kick panel location in addition to the rear armrest location, did you not add anything in the tweeter location for the door pods?

It looks like they are NLA on Crutchfield, but they are still available on Amazon.

Yeah, I moved away from the factory tweeters. IMO, the biggest weakness in the system is not a lack of highs, it’s the lack of fullness and low/midbass. Since the Infinitys are 2-way coaxials, the front kick panel speakers and rear armrest speakers still provide plenty of high-frequency output, an do a solid job covering the upper range from those locations.

I also had leftover dynamat and polyfill from my jeep install, so I added that into to all four speaker openings too, to try and improve the overall sound. I'd say it's definitely better, but honestly, it’s hard to make a major leap in this setup without a newer head unit, larger speakers, and/or a sub.

A component setup would be the cleaner long-term solution, but the Infinitys were really cheap (I got mine on sale too). So I prioritized simple installation, price, better overall output, and tried to avoid an overly bright result.

[reelizmpro]

Premium sound was an option on 91 318i's so it may not have the door sail tweeters.

[eco325iX]

MaCheFai, these are two-way speakers. Since you utilized these in the front kick panel location in addition to the rear armrest location, did you not add anything in the tweeter location for the door pods?

It looks like they are NLA on Crutchfield, but they are still available on Amazon.

[MaCheFai]

I swapped my speakers in my '91 318 convertible a while back. I went with a set of infinity reference 5032. Was pretty painless and fit into the front and back armrest positions

[eco325iX]

bradnic,

Stock OEM+ is the goal at this point. That said, I would like to have the factory radio and amp rebuilt, then maybe in the future when other projects are finished I'll consider an aftermarket amp and upgrade the speakers if I feel they are needed.

Thanks for your help offline as well.

[bradnic]

reelizmpro has provided some good advice as usual.

all USDM convertibles came with Sound System, which included the Quadroboost amplifier mounted in the trunk, behind the rear seat on the driver's side.
- The front kick panel speakers and door tweeter pods are the same as those used in coupes and sedans. It is a component setup with the 5.25" kick panel "mid-bass" speakers including a passive crossover for the door tweeters.
- convertibles used standard 5.25" speakers with no rear tweeters in back. Honestly they're pretty poor quality.

The most important thing is to decide what your audio goals are. You already have sound system, so you can keep your OEM radio and trunk amplifier, and have them rebuilt. If you don't mind losing the tape deck, you can install a BA31 kit in the CM5908 and get far superior sound quality using bluetooth and your phone (also hands-free). Also available are built in midrange tone control, track info and spectrum analyzer display right from the factory radio. You can even convert the entire system to an OEM+ radio only setup with 35 watts per channel right out of the radio itself.

[eco325iX]

At this point I'm not in need of the door pods, mine are in great condition, none of the mounting tabs broke while removing them. I do need some replacement tweeter speakers, I've been looking around at what is available.

Over the weekend I tested the five working speakers (the driver's side tweeter is dead) with an mp3 player and an audio cable that I clipped, they all work. This leads me to believe the head unit and/or amp are the problem. When I find some time I need to research how to test these pieces of the puzzle.

[Vincenze]

There are 3D-printed covers for different tweeters.

Here is one for your Alpines, but they are made in China, not the USA.
I don't see pins to hold it in the body.

https://www.myclassicparts.com/product/bmw-e30-tweeter-trim-cover-with-optional-speakers/

Garagistic also sells covers.

[eco325iX]

I would like to keep my CM5908 head unit and have it serviced to restore all of its functionality. As I had mentioned earlier, I'm planning to restore this vehicle back to its glory days, but with some OEM+ modifications. I'm beginning to question if I should replace the original amp or keep it? I know it's under powered from what everyone says, but I'm not planning to put a sub in the trunk. Nobody will ever see the speakers because they are hidden behind the door pods, kick panels and rear panels, so upgrading those makes sense to me and not purchasing genuine BMW speakers to replace them. The door pods were easy to remove and none of the tabs broke, these can be reused.

I had previously read through the thread by sna77 before creating this post. I appreciate the suggestion of procuring the audio equipment from abroad, but I would like to source the speakers from here in the US, just in case I need to return something and not have to pay exorbitant shipping, tariffs and potentially return shipping rates.

I guess I need to make a decision on which speakers are available...

[Vincenze]

This guy used Italian speakers, but he also installed a subwoofer.

https://www.r3vlimited.com/board/forum/e30-technical-forums/car-audio-electronics/10113602-winter-2024-projects-1992-convertible-interior-build-thread-mostly-ice

[Vincenze]

I did a quick search around the web for the door pod with tweeter speaker and it looks like some dealers are still selling it, but for around $165. I'm of the opinion it's time to find an aftermarket replacement for the tweeter(s). Should I purchase just the tweeters or look for components for the front kicker panel speakers and tweeters?

If your system works sometimes, but then produces hissing sounds, then the main problem should be with the head unit made by Alpine.
It has moving parts that are old and oxidized.

It's actually wonderful that you can buy original tweeters plus surrounding plastic frames. These frames have plastic pins that often break out. (Only one side is actually available.)
You have to search for aftermarket tweeters that are exactly the same size, or you won't be able to install the plastic frames.
There were DIY threads about them.

[eco325iX]

If you are replacing both tweeters, then mind as well get the components and have all new Alpine speakers.

I definitely would, but Alpine does not make a 5.25" component set, they have a 4" S2-S40C, 6.5" S2-S65C and 8" S2-S80C available in round. It looks like options are:

Pioneer TS-A1301C
Polk Audio DB 5252
Infinity Reference REF507CF
Focal ASE 130
JL Audio C2-525

...unless I can find some Alpines somewhere?

[reelizmpro]

If you are replacing both tweeters, then mind as well get the components and have all new Alpine speakers.

[eco325iX]

Update: I removed and tested the driver's side speakers. All the speakers are genuine BMW speakers, however the rear armrest speaker has a part # of 65131386544 which also looks different from the passenger side rear. One of the POs must have replaced this one. Here are the test results:

Door pod tweeter listed at 8 ohms ~ tested at 0.0 ohms
Front kick panel listed at 4 ohms ~ tested at 3.9 ohms
Rear armrest listed at 4 ohms ~ tested at 3.2 ohms

The door pod tweeter had a loose connection terminal, I tried to reset it in the slot and wiggle it around while testing to see if there would be a closed circuit, but no luck. Since it was dead I figured I'd get out the heat gun and remove the speaker from the pod. I found that the micro red wire for the negative terminal was severed, I tried to test it with the multimeter and 9 volt battery, no luck, it is dead.

I did a quick search around the web for the door pod with tweeter speaker and it looks like some dealers are still selling it, but for around $165. I'm of the opinion it's time to find an aftermarket replacement for the tweeter(s). Should I purchase just the tweeters or look for components for the front kicker panel speakers and tweeters?

[eco325iX]

Guys, I appreciate all the advice and thanks for hanging in there with me. Surprisingly this is the first vehicle that I have ever had that has audio problems, so this really isn't my wheelhouse. I watched some YouTube University videos about testing speakers with a multimeter and 9 volt battery. The following readings are for the passenger side speakers:

Door pod tweeters listed at 8 ohms ~ tested at 5.8 ohms
Front kick panels listed at 4 ohms ~ tested at 3.9 ohms
Rear armrest listed at 4 ohms ~ tested at 3.4 ohms

All the speakers moved inward and outward when you switch the + and - terminals on the 9 volt battery.

I would say that these speakers are in okay condition according to those tests, it must be the head unit or amp. I'll test the drivers side speakers tomorrow.