Hi Everybody
I was just wondering how have people positioned their centre channel drivers (orientation and location) How and where do you mount the tweet? ( had a idea of mounting onto the dash firing towards the windscreen and some added T/A for effect). What size mid driver are people using?
And if anybody has any other hints and tips, would be much appreciated.

Cheers
The Beaver

i use a centre channel in my cars prologic II system. the mid-range driver is mounted in the center of the dash (obviously) where the ashtray/lighter used to be, which is at the same level as the gear selecter. the driver is aimed up slightly such that it points at the samne level as the headrests, roughly. the driver sits in a custom MDF/bog panel made to replace the original panel and blend in.

i use a Boston Acoustics 5.5LF (5" driver) which works well and goes low enough to operate as a proper centre channel.

as for tweeters, you can put the tweeter(s) next to the mid which is the technically right way to do it, or you can try a higher location (as i did) like on the dash which can work well as it tricks your brain into seeing the centre image as slightly above the centre speaker (ie between the mid and tweeter), preventing the speaker from being easily localised.

ive played with centre channels a fair bit, any other questions let me know

you don't happen to have a pic of that set-up do ya??

well i dont have any decent pix but the following is all i have and should give you an idea of how mine is setup:

http://homepages.ihug.com.au/~staranto/ima...ot_interior.jpg

the centre speaker is partly covered up by the steering wheel, haha this pic was taken a while ago now by somebody at a meet, a few things have changed, but most is the same - it should give you the general idea. for daily use, i have black clothe covers for the centre and side speakers to hide and protect them.

the centre uses the airspace inside the dash as its 'enclosure' which i have stuffed with alot of dacron, and this allows it to operate in proper infinite baffle. its important for a centre channnel to be able to play down to 70-80hz as the centre does alot of work being the primary imaging cue, so if it sounds thin your music will sound thin. also, equalisation (in my experience) is vital to getting the centre and L/R drivers to blend together, without it chances are the centre will sound 'different' and ruin the illusion your trying to create.

If i have 3 way dyns as L-R channels, would 3 way centre channel intergrate well, or just overkill?
Thanks for the reply T-Bro

Cheers
The Beaver

a 3-way centre channel - hmm, never thought about that! well i guess it would integrate, but the problem will be, where do you fit all those speakers? the most critical for imaging will be the mid-range and tweeter obviously, so if you can get those nicely centred it will work well, but you also need the midbass whose location is less critical, but still best centred also, maybe somewhere in the centre console. my own front stage is 2-way for L/C/R and it works well enough without cramping this too much - if you have a big car i guess you could do the 3-way thing, do you reckon there is enough room?

I dont think that i could fit it in without totally reworking the centre facia. But could be done. I know that it is too much, but i was just worried about the centre channel blending. T Bro do you think two way will work?

a 2-way centre will probably work well, using the same model midbass and tweeter as used in L/R channels will help. i would not give up the midbass for the centre, as it will be important to maintaining impact and weight (most information in a recording is centre stage) and if you cross it over appropriately it will handle midrange too. to get it to blend well, i would suggest an equaliser dedicated especially to the centre channel (based on my experience) so that you can 'voice' the centre such that it blends with the left/right speakers. so yeah, dont be afraid to go with a 2-way centre, also play around with your decoders settings to achieve the best blend (what format are you using, and for what type of media?)

I have PXA h700 which i think has 31 band eq for the centre channel, so i might get someone who knows what they are doing. It uses Dolby digital and Pro-logic II. My main uses will be for 2 channnel stereo but also a bit of DVD. Do you think a 5.5 dyn driver will go well with 7" dyns.

Cheers T bro, youre really helping me alot.

The beaver

happy to help i have 6" boston pro's in the doors, and a 5" boston pro in the centre, and it works well nad is pretty seamless thanks to the equalisation and setup. the format i use is dolby prologic II which is excellent for regular CD's (ive been using it in 3.1 but am about to experiment with 5.1). PLII provides a 'centre width' adjustment which allows you to mix the centre image into the L/R channels, to achieve a slightly wider and more natural centre image. also, using DPLII's individual gain controls on each channel by attenuating the channel nearest you a little (ie the right channel) helps alot. add some careful equalisation of the centre channel thanks to your alpine unit, and you have the ingredients for awesome sound as for using dolby digital for DVD's etc, i dont have any experience with it but the basic principles are the same as DPLII to getting good sound. as for regular stereo, the centre will be off totally so it wont matter. but yeah, you will be surprised how low a good 5" driver can go if you mount it properly, you should have good luck with it, stick the tweeter wherever you like, keep it on a long lead in the beginning so you can move it around and experiment.

Am I right in assuming that a sealed infinite baffle combined with heavy deadening would provide the results I am looking for, or 'try' and build a box for the driver.

Mate, I am on a roll coughs, actually its you T Bro

i guess it all depends on your car and what you can do to the dash - there are alot of cars where fitting a good centre speaker just wont work without major butchery, and yet others (like mine) will take one easily as long as some custom work is done. have a fiddle with yours and see what room you have to play with, which panels you can remove, how much airspace is behind them etc.

i would recommend sticking with infinite baffle, as that is how your speaker is supposed to operate, and that is how mine is and ive have good results. for good clean midbass extension and attack, you want the following:

- a good amount of air space behind the driver, to allow it to get close to an 'infinite' air space as possible

- a good seal of the front of the cone from the back, it doesnt have to be an air tight seal (your dash aint air tight anyway!) but you dont want any gaps where sound waves can get back round and cause canellation.

- a solid mounting baffle for the driver, MDF works well and you can do as i did and line this baffle with sound deadening matt to make it as solid and dead as possible

- a non-resonant air space behind the driver, i stuffed my dash with dacron to reduce any echo or hollow/tinny sound, you also need to deaden any parts that will rattle because they will want to seeing as youre using the dash interior as a speaker enclosure, do a good job and focus on things like binding plastic panels, cabling looms, clips, screws, air con rods and dials etc

- a location that roughly puts the speaker on the same visual place as the left/right speakers and that angles it up towards the listeners heads, doesnt have to be exact but too high or low and your ears will know something is not right.

I was speaking to Yanddy of Audio Art & Tech today and he suggested using the 4" midrange ( which is a sealed driver) and ditch the 5.7" all together. Does anyone have any opinions of this? T-bro?

Cheers
The Beaver

when experimenting, i tried a 4" midrange and it worked well enough, as such a driver will generally go from 120hz all the way up to your tweeter. however that midrange you were suggested, being a sealed job, will have almost no midbass extension, so this may be of concern given that your centre speaker does most of the work, so if its thin, everything else will be too. you may be able to compensate if your L/R drivers exhibit good midbass (perhaps dialing in some boost will help), as your centre may go just low enough to fool your brain into seeing the midbass centred also. so while the midrange isnt ideal (what is in a car anyway, haha) it should make installation alot easier and give a reasonably good centre image - just make sure your left and right drivers can help it along.