[kaigoss69]

So I have been doing a lot of thinking. I have bought a Focal 4" 100 KP component set for the front doors, but I have had some doubt about the 4" mids and their ability to close the gap in the midbass department to the underseat SWS drivers. Ideally, I would not want the SWS to play higher than 100Hz, and the let the door mids take over at 100Hz and up for best possible imaging and to allow the SWS to "focus" on playing mostly sub-bass which is what they were designed for.

I have come to the conclusion, after doing a lot of research, that the Focals probably can't play much lower than 200Hz at the higher volume levels. This leaves me with a gap between the door mids and the underseat subs. In order to bridge that gap, I am now wondering if it were feasible to install 5.25" mids in the rear doors in order to provide the much needed help in the area of 100 - 200Hz. Since I will be using a Bitone.1 processor, I do have enough channels and "tweakability" at my disposal in order to do this. Since I had a similar set-up in my old car, I am also quite sure that with the help of the processor, the rear door mids can be made to "play" up front, so I am not too worried about that but rather with the selection of the correct driver.

Depth is surely the number one hurdle to overcome here. Are the rear door mounting dimensions the same as for the front (we are talking about an e90 here) or is the depth even less? I know that the following to fit in the front doors:

- DLS RS5/RS5A
- MB Quart RUA 213

Which one of the above would be the better choice and are there any others?

Are there some DIY speakers (Dayton, etc) available for this specific duty? This only needs to be a "midbass" driver, not a "mid".

Thanks in advance for any insight you can provide.

[Dackz]

I think you would end up with some imaging issues. Behind you is behind you any way you strike it. I think you should use the underseat stockers as midbass bandpassed from like 50-200hz or so and put in a trunk sub from like 60hz and down, IMO. Not sure if the bit one has bass timing but if it does, you can even get it tuned to sound like its in the front.

In my setup, I just have trunk sub and bandpassed stock subs on a PDX-5 and I think its great midbass wise?

[VP Electricity]

I'm not sure why you don't want to run the SWS higher... do you have any advanced EQ capability?

I am tuning and RTA-ing my car tomorrow so stay tuned for RTA screen shots...

[kaigoss69]

Originally Posted by VP Electricity

I'm not sure why you don't want to run the SWS higher... do you have any advanced EQ capability?

I am tuning and RTA-ing my car tomorrow so stay tuned for RTA screen shots...

This is why:

(Stolen from mangotangoe over at 1addicts, he's got it crossed over at 180 Hz)

[VP Electricity]

Then he shouldn't label his graph image "stdsws8nocrossover", then

I don't find this worrying nor surprising. Remember, speakers have output in the stopband - the band past the xover point, and these outputs sum together acoustically. Don't assume that highpass and lowpass points all have to match.

Also, remember that we tend to make assumptions about sound from seeing these curves. Many shapes which look "bad" sound surprisingly good, and unless you are a way dedicated SQ hobbyist, you won't think badly of many nonflat curve shapes.

His final graph:



Which looks great other than a NARROW notch at 200. Given that neither set of speakers has a dip at that freq, and the fronts have a NARROW SPIKE at that freq, I think he should try reversing polarity to the SWS8 (I would).

But I would expect it to sound pretty good. Do you have a link you can send me? I'd like to read what he's done.

[kaigoss69]

Originally Posted by VP Electricity

Do you have a link you can send me? I'd like to read what he's done.

http://www.1addicts.com/forums/showthread.php?t=299508

[VP Electricity]

Looks like he got pretty good results for one of these systems without any EQ. I guess maybe we'll see why I spent on 4" components with 2" voice coils