General upgrade for C5 x7

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Xantippa
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Re: General upgrade for C5 x7

Post by Xantippa » 13 Mar 2016, 19:48

I would forget about installing "subwoofers" in rear doors, and would go with this: http://www.ebay.com/itm/Citroen-C5-2-Se ... SwnH1WXWJg

89€ including shipping for custom made enclosure that fits perfectly isn't much.

vborovic
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Re: General upgrade for C5 x7

Post by vborovic » 13 Mar 2016, 20:10

Since I have the subwoofer already (Philips), I'd only go for the 2 new tweeters, a pair of 1-way woofers for the front and a pair of 2-way woofers in the back doors ... shoot me, I don't know why, but Hertz is somehow the closest choice for me, not looking at their top range of course, I can get a pair of speakers, new, for like 65€ ... I'd like to have a warranty and a service that is fairly close in case something goes wrong ... if it wasn't for this, I'd be willing to purchase any speakers worldwide ... but, nothing is definite so far

vborovicfan
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Re: General upgrade for C5 x7

Post by vborovicfan » 13 Mar 2016, 20:16

just facts
1)10 inch subwoofer in this 15 liter closed box will not play lower than 80Hz. too little volume
2)small 8inch subwoofers in rear doors on the other hand will reproduce bass down to 40hz

it depends what you want from car-1) refinement and true timbre to listen for organ music or clasical works for example or
2) boom and tizz upper bass (like young fellows drives on streets with full volume up)

Xantippa
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Re: General upgrade for C5 x7

Post by Xantippa » 14 Mar 2016, 07:01

vborovicfan wrote:just facts
1)10 inch subwoofer in this 15 liter closed box will not play lower than 80Hz. too little volume
Yes it will when you select right subwoofer and use correct low pass filter. In fact I have now an 12" subwoofer (Pioneer TS-SW3041D) in 14l box inside sparewheel, and it goes easily down to 20hz when measured - and it also sounds good. It's just a matter of selecting right parts and adjusting your system correctly. You'll never get as good sound from 8" subwoofer in a leaking door.

vborovicfan
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Re: General upgrade for C5 x7

Post by vborovicfan » 14 Mar 2016, 09:45

Xantippa wrote: Yes it will when you select right subwoofer and use correct low pass filter. In fact I have now an 12" subwoofer (Pioneer TS-SW3041D) in 14l box inside sparewheel, and it goes easily down to 20hz when measured - and it also sounds good.
we cant deny physic-
1)car internal voluem is too low to reproduce anyhing below 40hz, even rooms smaller than 40m3 are not ment to this.
2) we can get 20Hz in 14 liter box- when mesure neafield response of car subwoofer. but it will be around -25db to its reference spl output level @100hz . so we have large bump at 80hz just lieke that. and the bigger driver you choose in such bax size the less lowest bass you achieve.

in fact 5inch subwoofer(small one dedicated mini sub) in 14 liter box plays much lower than 12 inch in same box.

the only only subwoofer I know of that will play low in small boxes is
http://www.scan-speak.dk/datasheet/pdf/23w-4557t00.pdf

in 2008 i have made prototype line array with 16 pieces of those subwoofers(350eur/each at that time) ,which were supporting 10x accuton c222n woofers 650eur/each ) mids were accuton (550eur/each) and tweeters was focal utopia Berylium (home versions)
Image

those speakers played loooow and spl is prety much OK (because many of them were conected) - with one single subwoofer spl is very low-its very quiet..

in car its 8inch neeed two passive resonators and its mass are very high with low Fs and eficienty is 79bd/w/m only. it achivees downs to 30hz theoreticaly in cars box 25liters or so. thats pretty much what we have achieve when speaking about subwoofers in small boxes.

the only way you can get low frequencies from such low volume box is active QE in bass, somehting like +14db at 30hz or so..

Xantippa
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Re: General upgrade for C5 x7

Post by Xantippa » 14 Mar 2016, 09:55

So you don't know that car amplifies bass frequencies at 12db/oct below certain frequency? It's actually easy to get sub-bass in car from small enclosure. You just find a correct subwoofer driver and install it to right size enclosure with Qtot 0,7 and you get flat bass response below 20hz. Read: http://www.diysubwoofers.org/projects/car/sub3/

"Current car subwoofer theory suggests that the best type of design for in-car use is a small sealed box, based on the observation that the 12dB/octave rolloff of a sealed box is a perfect match for the car's "cabin-gain", which is said to provide a free 12dB/octave to any subwoofer design, starting from a corner frequency that is dependent on the size of the cabin (the larger the cabin, the lower the corner frequency). Typically this corner frequency lies between 60 Hz and 80 Hz."

And I've measured my systems response with REW - there's very much sound coming below 40hz, trust me! :D In fact my subwoofer LPF is set at 40hz 18db/oct, so there's no bump in 80hz at all.

vborovic
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Re: General upgrade for C5 x7

Post by vborovic » 14 Mar 2016, 10:02

This is really becoming an interesting topic ... :)

vborovicfan
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Re: General upgrade for C5 x7

Post by vborovicfan » 14 Mar 2016, 10:06

all enviroments(except anaechoic chamber) amplifies bass. be it room , car- even WC room will amplify. but size is essential. its simple physic. car size is no more than 3m3

could you please send nearfield frequency response(let say from 2mm) of you car woofer (without any active corections just raw 12 inch drivers response in 14 liter closed box)?

Xantippa
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Re: General upgrade for C5 x7

Post by Xantippa » 14 Mar 2016, 10:53

Smaller the environment - more room gain. That's why car is so easy environment in this sense. :)

There are plenty of 10-12" subwoofers that do work under 20l enclosures in car, so that's not problem. And it would be way easier to install subwoofer with that enclosure than installing in the doors. If I had known about that before making that enclosure inside spare wheel, I would have bought that myself. Unfortunately that enclosure isn't available for Tourer.

I have only total system response somewhere at home, there you can easily see that there is plenty of bass below 80hz, all the way down 20hz. Can't make new measurements easily because my HU's line-level input connection is broken (DIY-adapter between car's own wiring and aftermarket HU consisting of needles broke when I took HU out and put it back in, there's plenty of wiring behind HU now :D ).

Btw it's impossible to measure from 2mm because subwoofer would touch the mic when playing sound. :-D Right place for measurement is drivers seat, I tend to listen my music there.

Xantippa
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Re: General upgrade for C5 x7

Post by Xantippa » 14 Mar 2016, 17:02

Here is one measurement. Measurement -signal was pink noise as mp3, and difference between bass and treble isn't nearly as big in reality. Sound is only bit more bass heavy when compared with my home hifi that has got flat response. But anyway you can see that there's bass reproduction below 80hz. That pothole around 30hz is caused by trunk floor that resonates at that frequency and "sucks" bass. Subwoofer is installed under trunk floor inside spare wheel.

Image

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GiveMeABreak
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Re: General upgrade for C5 x7

Post by GiveMeABreak » 14 Mar 2016, 18:02

Switch on, tune in and chill out! :rock:

KP
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Re: General upgrade for C5 x7

Post by KP » 26 Mar 2016, 21:29

If Deffo be interested to see any of the touch screens come up for sale as they will be uber rare.

Having said that today I've just completed an rneg to rneg2 upgrade. Screen and system is markedly quicker, and the Bluetooth streaming is a godsend as is having a USB port! Only thing left to do now is work out how the mic wires in :)

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Re: General upgrade for C5 x7

Post by vborovic » 26 Mar 2016, 21:42

I've decided to resume my touchscreen project with the Android tablet as a base ... the total cost will be maybe 1/10 of the genuine touch-screen set ... :D

Xantippa
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Re: General upgrade for C5 x7

Post by Xantippa » 27 Mar 2016, 15:31

Nexus 7 first gen with custom rom for car use?

vborovic
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Re: General upgrade for C5 x7

Post by vborovic » 27 Mar 2016, 15:36

Nope, an Acer Iconia tablet as a base with an external touch-screen digitizer that will be placed over the existing screen for the touch-screen functionality ... that way I'll have the original RT6, the TV tuner, reversing camera and the Android OS device (the latter the only one which will be operated with the touch screen) all on one screen