Essell55mb

Its surprising , but the BOSE 'premium'...... audio has no dedicated tweeters. So added some JBL GTO tweeters to the door triangles with a crossover connected to the existing mid/high drive unit in the lower section of the door.

For £60 , this has been a massive improvement in quality - you actually can hear the missing highs now. Interesting its shows the higher frequency response was there from the amp side but got lost at the frequency response of the drive units.

It was necessary to back the treble off a notch to avoid it sounding too bright but I would recommend this as a low cost audio improvement.

poptopclk

I was going to post about this, in my S500 the tweeters are there in that little triangle and it made me wonder why
the Bose sounds pretty good in the big salon yet sounds awful in the SL550 and I think you are 100% correct.
You should post pics and procedure and parts used...

m5zealot

I use to install high end systems in my youth. Are you sure the OHMs (2 or 8 OHMS?) on the tweeters match the output of the amp/head unit? If they don't, you can blow out the tweeters and/or overheat eh amp/head unit. Just curious. I don't know much about OEM installed systems these days but I know speaker impedance is still part of the rule.

http://www.audiogurus.com/learn/spea...ce-rating/1092

Essell55mb

hi, yes I know what you are saying, If you wired two identical drive units in parallel you would reduce the parallel impedance and hence you may run into problems pulling too much power from the amp.

However as I understand in this case, since you have connected the tweeter via a crossover and also the impedance of the existing mid/high driver will increase as frequency increases anyway - you are not connecting parallel impedances at the same point in the frequency spectrum
so as far as the amp is concerned it doesn't see excessive extra load.

Essell55mb

Following on from this topic, I still think this has made a worthwhile improvement on the BOSE premium audio HOWEVER I don't really understand why this system doesn't sound better overall.

Its a system designed for this car with lots of DSP options, but to my ears its an audio system that struggles with clear vocals and gets muddy with complex tracks. I know sometimes that audio
is designed for certain music types and I believe classical is fairly flat response - maybe thats the case with this design and hence sounds a bit lack lustre with other music types ?

Just wondered if anyone else had opinions on what it is with this system that could sound better ?

( although you could say the electronics in design are getting on for 20 years old, the previous R129 was praised for its sound quality ! )

bobterry99

I think this could be the case. Since the Bose amplifier incorporates equalization customized to the R230, the frequency response of the system presumably is flat and doesn't have the exaggerated base and lower mid-range that many people prefer with some types of music. However, I presume you have played with the tone controls and still aren't satisfied with the sound, so maybe there is something else.

fooschnickens

That's pretty much the hallmark of any factor Bose system. The only one I've heard that comes relatively close to surpassing "OK" quality is the one that came in early 2000s Miatas... MB shold have teamed up with Sony, the factory system in my girlfriend's Focus ST sounds worlds better than what I have now. Luckily I'll be changing all that around end of the year. Getting all the bits together to dump the entire lot and really bring it into the 20th century.

a32amg

Thank you my friend for sharing this very useful upgrade. As soon as I read your post I went ahead and bought the same JBL GTO tweeters. (That was a great choice BTW. It got 2 Ohm impedance which is same as rest of BOSE speakers. 2 Ohm car speakers are very difficult to find.)

Improvement is noticeable. Problem is that I am having trouble making these two small speakers integrate into the small triangles. The space inside the triangle is too little to contain the speaker. Currently I just attach the speaker to the mounting base came with speaker and use double sided tape to make it glue to the triangle. Everything looks… weird. You can see it from the attachment.

My goal is to make it appear to be as stock as possible. I am wondering how did you mount these tweeters. Any input is greatly appreciated.





Above: Crossover came with tweeter


Above: JBL GTO speakers used. Just for reference in case someone is interested to know.

Essell55mb

Hey a32amg, no problem - glad you liked the improvement !

So at the moment I don't have any photo's of the car, but I can describe what I did:

1. As you have identified there is very little room within the door triangles, so I did mount mine on the outer surface of the triangles. I actually had a friend make a small plastic wedge ( circular ) that angled the tweeters towards the centre of the car - head height. This plastic part was actually grown on a rapid prototype plastic machine.
The part was fixed to the triangle via a small screw that went into a thread in the plastic wedge.

Surprisingly this method does look fine, I thought it may look aftermarket but quite happy - since also I prefer the factory look with mods.


2. As an alternative to a custom part, I did consider using a piece of plumbing pipe the same diameter as the tweeter, then cut it an angle, spray it satin black for the same effect.

-see this, the same idea: angled tweeter mount. ( for this car, the tube will be MUCH shorter, so the tweeter sits almost touching the triangle on its shortest side )



3. Also it may be worth considering buying a cheaper tweeter from ebay etc... that already comes with an angled pod and just use the mounting hardware for your jbl tweeter. ie - a surface mount angled pod.

Essell55mb

using the picture from the link, https://www.hdforums.com/forum/touri...g-mirrors.html

I have done a crude picture annotation to show the shape of the pod I used:

Jimmy325

Essell55mb

Jimmy325

Frederick NL

Essell55mb