Has anyone replaced the stock Bose door speakers with an aftermarket unit? I've recently taken it upon myself to get my audio working. I'd like to keep the Bose head unit functional. I'm not interested in replacing it with a newer Bose model from a Miata, etc.

If the stock door amps are fried, is there a replacement for them or a source I can easily go to to get them repaired?

But it is a must to keep the Bose head unit and Snake in the trunk functional. I'm thinking it must be possible to get a Bose head unit working with speakers that don't require their own amp.

I know this is an uphill almost impossible feat so I'm looking for advice from someone that has done this exact thing.

 

it used to be that you could send the stuff to Bose and they could repair it, you might want to see if that is still a thing
Bose used speakers that were an odd impedance, so finding stuff that is compatible is hard

 

I've found a few threads from 12 years ago mentioning the same, that Bose would rebuild/repair equipment. I'll reach out and see what comes of it. I've spoken to Bose customer care and their only recommendation is to speak with the local Mazda dealer.

What complicates things is I don't have the Bose head unit or the speakers. I do have the door amps and the rear hatch amp/speakers. Instead of going through the hassle of sourcing speakers, installing, verifying the amps work, if not rebuilding/replacing, I rather find a way to install aftermarket speakers with a single amp that drives all the speakers. The reason for the amp is so I can use the Bose head unit.

For now, I'll hope for the best with the Bose contact info I found. Replacing/Rebuilding everything would alleviate having to wire in an amp and all new speakers, if even possible with Bose head unit.

 

​​​​​​You can't just replace the bose amp with an aftermarket counterpart unless that amp is of the same impedance as the bose speakers, head unit.

But I'm confused. In your first post you say you want to keep the bose head unit functional but in your second reply you state you don't have the Bose head unit.

Dude I've tackled the bose stuff before but I don't have the time to write this long convoluted explanation about what happens with impedance mismatch and how that translates to degradation of signal quality. If you're interested send me a pm and we talk on the phone for like 5 min or so. That way you can make up your mind on which way to go

But here's the gist

1)Bose works at a different impedance than conventional audio equipment. it's around 1 ohm IiRC. Conventional stereo systems are typically 4 ohm. The mismatch results in the audio coming out of the speakers as not being very good. Which defeats the whole purpose of having a Bose system.
2) Bose headunits are passive and that is why an amplifier is needed at the Bose speaker end. Conventional head units supply power and if used with a Bose speaker that has an amp it will over drive it and sound like **** (just ask how I know lol)
3) they used to sell an adapter/impedance transformer + signal suppressor (remember Bose speakers are expecting a passive signal) that allowed a non Bose head unit to be used with Bose speakers. But I'm not sure not sure if there is one available that works the other way. Meaning Bose headunit to non Bose amp and non Bose speakers.

 

just a note if you went the other way and used 1 ohm speakers on an amp that is expecting more (4 or 6 ohms are pretty common), it can blow the amp up

 

Not mentioning that I didn’t have a Bose head unit in my first post was intentional. I didn’t want to make a case against myself where comments would suggest, simply just replace it all.

Montego - That is the other option I’m after. Bose head unit, to a single amp that powers all the aftermarket speakers.

My first option is to use the stock amps and source some aftermarket speakers that work. I’ve only been able to find 4” 2 ohm speakers online. I’ll have to keep pushing with Bose to see if they have speakers and amps in stock. If not, I hope my amps work and if they don’t, then I have an option to get them rebuilt.

 

Definitely. Having a high VSWR at the amplifier output can definitely damage it.

 

assuming that your amp and speakers are 4ohm, I'd look for a 1:4 impedance transformer (aka balun). It does exactly how it sounds, it changes the impedance based on the ratio listed. Input impedance is 4 tiles less than the output impedance (or the other way around if you flip it over). Not sure if any exist for audio components but it's worth a look.

As far as I know Bose is the only manufacturer that makes 1ohm system speakers. BTW yes impedance not resistance.

To help you understand why system impedance is important picture this: let's say you are cruising down a super long single piece of sidewalk on a skateboard. Everything is fine you are cruising at a steady speed. However, the piece of sidewalk is ending and a new section is coming up. But you don't fret because the construction worker that built it was awesome and the seam between the two pieces was almost perfect and the two slabs of concrete.were.level to each other. So you just glide on though. This is basically an impedance matched system. Impedances line up and there is maximum power transfer between the two sections/components.

Now what if the construction worker sucked and the two slab sections are actually way off from each other. Not only do they not line up but there is a big gap between them. Whatever happens it won't be a smooth transition on the board. You will lose speed and possibly fall. This is basically what impedance mismatch is. Bad **** happens.

Now obviously my example is not a direct one to one comparison and is failing to take frequency into account (which is what makes the most difference). But it is only meant to help you picture why it is not good to not match systems. In reality when a mismatch occurs between transmission lines, power is reflected back into the incident wave causing loss in power being transferred.

 

The Bose Automotive number found in posts from years past is no longer in use. I'll try reaching out to Ray Crowe to see if he has some direct contact info or knows how to source pieces. Not being able to source these parts makes me SMH at the 6 figure price tags on recently sold RX7's.

 

If you want to repair the stock bose amps theres a great write up on it here: https://www.rx7club.com/3rd-generati...-amps-1150545/

Usually the old capacitators are fried up and just replacing them will do the trick. If you are handy with a soldering iron and know how to rework PCBs it should be no issue. If not you can take it to an electronics repair shop.

 

Researched something similar when I was trying to get my system working and thought I'd share.

If you're searching for speakers and can't find them anywhere for an FD, try searching for the Z31 Nissan 300zx (Fair lady depending where you're from). They happen to have the same Bose Speaker box in the front doors.

 

also the 99-2005 miata, and Rx8 had bose optional. i remember having to change the relay in the amps....

 

Now in my possession is a stock FD Bose unit and some door speakers. The speakers can be sourced online. They're rated at 1 ohm and full range. Link below. Originally I was hesitant as they're listed as 4 1/2" speakers while the door cutout is 4". I was afraid they wouldn't work or the box would need some modifying. To my surprise, they fit perfect. The back of the speakers seals to the box and the mounting holes line up pretty close. Speaker depth seems perfect, no bracket or spacer needed.

For now, this is a win.

With a small amount of re wiring, I'll be one step closer to having audio in my FD for the first time.

https://www.parts-express.com/GRS-RS...922?quantity=1

 

Where could I source a single din rail for the FD? Is it specific or would a generic one work?

 

If you want to repair your factory Bose amplifiers, check out https://carstereohelp.com/mazda.htm. They have now repaired ALL of my Bose amps, and everything is working perfectly.

 

Any update on these speakers being used with the stock Bose setup? I'm very intrigued as I want to keep the system as stock as possible, but if the speakers can't be fixed, an exact replacement would be great.

 

Sadly, the head unit is still sitting on the shelf. I need to fix some wiring. The previous owner tried modifying the wires for an aftermarket unit, which didn't come with the car.

Maybe the push I need. The Bose units were tied into the cars security system so that is another hurdle I may have to overcome. Still need the end caps.