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View Full Version : How to Make a Bora slower..



Mr İharisma
13-03-2008, 08:28 AM
Answer is to add more weight. What better way to do it than to add a stereo :D The car in question is a 01 MKIV Bora 4motion. I would like to thank FHRX for doing the earthing kit and sub box, another awesome job.

Source for the car is a Pioneer 8650mp, 6.5v pre outs, T/A, 11 band EQ some of its better features. I have also added an Ipod adapter so that the Ipod can live in the glove box away from eyes and be controlled from the front.

From the engine bay the standard battery, although quite good, had to go. I had an Optima D34 left over from my old car so straight in it went. Then of course the terminals where around the wrong way so that had to be changed as well. Just for fun I decided to add an 300A earthing kit to the engine bay as well just for good measure. Battery has since been replaced with D34m blue top as it has a second set of terminals so I can crank it all day and if I need to jump start I wont damage my gold terminals. Plus its easy to hook up the old battery if I am out somewhere at a show etc.

Mr İharisma
13-03-2008, 08:39 AM
Then we move onto the front stage. After mush thought I decided to stick with un upgraded version of the existing Boston splits that I had. The SL-60's fitted the bill excellently. With separate dockable xovers it also meant that future expansion would be made easy as they will take bi amp and bi wire and have axis and atenuation control.

A custom 12mm MDF spacer was used for good mesure for the mids and the last pic shows where the tweeter was mounted on the drives side, high in the kick panel. Height is no problem as the stock grills up the top constantly fool people into thinking the tweeters are behind the factory grill. 2 sheets of Dynamat per door and a dynazorb pad behind each mid.

Mr İharisma
13-03-2008, 08:51 AM
Rears in this case are totally stock. They are faded out so I can not hear them anyways and HP @ 200Hz 12db/oct :D

Now I have 2 Audison amp with one being over 40cm long. The other is tiny. The first SRx2 powers the front stage, it produces 2x 65WRMS for the Bostons and the larger SRx2s power the sub with 1x 600WRMS. I really had no choice if I wanted a stockish looking car but to mount them on the rear of the sub box.

The sub box is a gem made by FHRX. It has 1.1cuft sealed internal capacity and features a 36mm MDF backing, 2x25mm MDF sides, 25mm Perspex across the front, 2 red leds, mirrors and dec board. The first lot of picces are with the older Boston G5 124 that I had and the last ones are with the new OZ Me 12.2 that I have. The install was designed to be as stealthy as possible with the hidden boot and engine bay being the only stand outs. Dec board is currently in the process of being re-done.I hope people can get some idea's from this :)

ranton-inc
13-03-2008, 11:37 AM
Cool Stuff man!

Whats with the Foam balls in the sub enclosure tho..

what is this dyna sorb pad behind the mid..

and why arent your photos hosted offsite so you can display them loud and proud ;)

Lukev85
13-03-2008, 12:39 PM
nice hook up, makes me wanna post up pics of my boras sound system lolz

MattyT
13-03-2008, 01:18 PM
An excellent install. FHRX is one of the premier audio guys in OZ!

I really wish there was an equivalent guy over here in WA. I've had my stereo at 3 different stores and none of them can make it sound good :mad:

Mr İharisma
13-03-2008, 06:52 PM
Cool Stuff man!

Whats with the Foam balls in the sub enclosure tho..

what is this dyna sorb pad behind the mid..

and why arent your photos hosted offsite so you can display them loud and proud ;)

foam balls was an idea, sealed box and they bounce around. It was to hard though to keep enough in so it doesnt work as well as I hoped and I couldn't be bothered to take them out lol.

Dynazorb is an absorbant pad that you mount behind a speaker to absorb the rear waves. The theory is that is will help elimate the rear waves interfearing with the next cycle from the front hence reducing cancellation and making you speaker louder. They cost about $40 a pair. Focal Chant are better by they are $100 :o

I have some picces on facebook lol :rolleyes:

glidn
14-03-2008, 07:43 AM
yeah nice bit of gear, i just cannot quite figure out the location of the tweeters, or least the one tweeter that is, i could not find the other tweeter.

Does that location give you very good imaging?
Also does it create the rainbow effect all?

Just really interested.

Soundofav6
14-03-2008, 09:54 AM
thats some awesome gear you have there Mr İharisma.

Firstly, I always LOVe the bora. Secondly GO the BOSTONS !!

One question, for the speaker on the door, do you have seal the speaker inorder to make use of the Dynazorb ?

glidn
14-03-2008, 10:30 AM
thats some awesome gear you have there Mr İharisma.

Firstly, I always LOVe the bora. Secondly GO the BOSTONS !!

One question, for the speaker on the door, do you have seal the speaker inorder to make use of the Dynazorb ?

door does not have to be sealed for dynazorb to work.

Soundofav6
14-03-2008, 11:44 AM
Ic .. thanks glidn.

Also, whats the rainbow effect ? is that what happens when you listen to Elton John Lol

glidn
14-03-2008, 03:27 PM
Ic .. thanks glidn.

Also, whats the rainbow effect ? is that what happens when you listen to Elton John Lol

I'll give you the proper explanation when i find it.

There is abit to this. But generally the sound it abit all over the place.

Instead sounding in front of something or behind something. It sounds like the trumpets on the dash but the bass drum is on the floor of the car, in a nutshell.

I found a really good article explaining the "rainbow" effect and what you can do to try and prevent it from happening.

Sometimes simply relocating the tweeters can make a huge difference into how a system sounds.

Soundofav6
14-03-2008, 03:50 PM
So it is a "bad" thing ?

I will google it in a sec.. sounds interesting.

Mr İharisma
14-03-2008, 05:34 PM
yeah nice bit of gear, i just cannot quite figure out the location of the tweeters, or least the one tweeter that is, i could not find the other tweeter.

Does that location give you very good imaging?
Also does it create the rainbow effect all?

Just really interested.

Ill take some better pics of both tweeters on Sunday. I only posted the pic of the tweeter on the drivers side. The problem is all tweeters have a different response so it wont be perfect for all tweeters but it may be worth looking around that are to find it.

Imaging is awesome, it took about 2.5hours to get it right. Everyone comments on how good the channel separation is. Depth is great but of course height isn't perfect ( I am 190cm and sit in the car straight up, bad back lol ) but on the whole it is good. Most people can not tell. As with all well staged front's, the sound is coming all from the front. The sub is a little out of phase ( by about 60-80deg ) but on the whole blends in very well.

Gear is ok, its by no mean great but of course they are installed to maximise the potential. Dyanzorb pads are only there to absorb the rear waves. They are only one part of improving free air response from a mid. They can be used in a sub box to...

qsilverza
16-03-2008, 10:09 PM
I like the front hook with the distro block and optima.

Have some SL60's hooked up in my Dads mitsubishi, they sound good and go loud.

Interesting spot for the tweeters, I tested the depth in the standard location and couldnt/wouldnt get them to fit without cutting, thinking about mounting at the pillars...

Like the red leds on the box but not so sure about the look of it.

All in all, a nice install.

Greg Roles
17-03-2008, 08:54 PM
Nice work!

So mounting tweeters level with the mids gives a more focused sound, that is the high and low "sound" like the are from the same place?

I thought the go was to mount the tweets up high as higher freq is directional, whereas the mids and especially the sub are non directional.

Why run splits then??

glidn
18-03-2008, 07:29 AM
Nice work!

So mounting tweeters level with the mids gives a more focused sound, that is the high and low "sound" like the are from the same place?

I thought the go was to mount the tweets up high as higher freq is directional, whereas the mids and especially the sub are non directional.

Why run splits then??



Alrighty, here is a myth not many people seem to understand.

Only subs are non directional, anything about 150 - 200HZ is directional.

Therefore mounting your tweeter as close to the mid as possible is usually best. But not always, with technology of what it is today, you can often mount them apart and by using time alignment crossover settings and gains you can fool the system that sound like the mid and tweeter are near each other.

ranton-inc
18-03-2008, 07:35 AM
with technology of what it is today, you can often mount them apart and by using time alignment crossover settings and gains you can fool the system that sound like the mid and tweeter are near each other.

Like we have done so in the R?

Mr İharisma
18-03-2008, 08:29 AM
Like we have done so in the R?

Yeah it is looking really good mate, I don't know if you have mounted your tweeters yet but I'm going to get piccies of them today for you to much around...

Good luck eliminating those rattles from the 8's!

I tried taking them off my camera but it's not wide enough so ill use a work camera with a wide angle lens to fit it in ( I work at a camera shop )! :D

Mr İharisma
18-03-2008, 06:24 PM
Ok so it took a Tamron 14mm f2.8 lens to get it but here they are. Both left and right side tweeter mounting and mid comparison.

Mr İharisma
18-03-2008, 06:34 PM
Ok for all those wondering about tweeter mounting, this is taken from the Fhrx site about the problems of mounting tweeters.

Okay, stop and think about a concert for a second. You don't sit with your back towards the band right? Rather, you want the sound in front of you. Likewise you want to be in the first row, be dead center of the band on stage and depending on your personal preference you might like to be slightly below the sound (as is an audience member) or slightly above the sound (as a conductor is). This is the image we try and capture inside cars today and tweeter positioning plays a large role in achieving this phenomenon. You cannot just simply slap tweeters in anywhere. To get a decent stage you need good width, height and depth - preferably mirror-tip to mirror-tip, floor to roof and as far down the bonnet as possible.

Where to mount them then? Kick panels, sails or elsewhere?
We often see tweeters mounted up high on the sail area on the door or down in the kick panels. Both these work well but can suffer from similar issues. The problem with the sail mounts is this; think about the position of your ears in relation to the tweeters. One speaker is belting the high pitch tunes out about one foot from your ear where as the other tweeter is triple, quadruple or quintuple that distance away. The image has no choice but to be right out the side window. Sheer laws of physics govern this fact.

If you place the tweeters down in the kick panels then the right speaker distance is about three feet and the left speaker is about four feet away. The problem is not utterly eradicated but it becomes a lot less noticeable as the distance separation is reduced (by up to half sometimes). However using the kick panel method the stage can be a tad low (the kicks are often used on cars with no factory tweeter location to avoid the cost of custom A-pillars or sails too). Remember tweeters cannot be placed anywhere where they fire straight into ones feet so you have to be more careful about their placement on both sides and more often than not this results in them being mounted very high up in the kick panel, quite often well out of sight and well up under the dash - this is also good for security too.

The final mounting place of your tweeters depends what you desire from your system and what your budget is. As mentioned above; when choosing a tweeter mount in order to achieve a great sound stage you're always faced with various issues. Put the tweeters up high and forward and you'll get good depth and height but the stage width can sometimes suffer. If you put them deep in the kick panels you tend to get good width and depth but the height can sometimes suffer. Seems you cannot win sometimes, especially when you factor other things on like reflection issues. Experimentation is the best strategy. Remember too that tweeter location can also play a role in ambience too. If the tweeters are positioned correctly (whether in the kick panels, A-pillars or even behind the review mirrors) they will help the whole component set fill the car with high frequency sound - not just way off in front of you.

There are two other issues to consider when choosing where your tweeters will go too. Cost is one because to mount the tweeters successfully in the A-pillars there is a good chance you're going to require some custom work done and hence the price goes up. Then there is also the security issue too because people can now see your tweeters. Factor all these issues in when you are deciding.

MKIVF
19-03-2008, 09:49 AM
Another great place to mount the tweeters are on the a pillar. I find with the tweeters in the panel, the stage height is too low. A way to circumvent this is by putting a second pair in the a pillar, but I prefer not stuffing around.

Good choice of equipment. Was this reccomended to you by Marty? As soon as I saw FHRX I felt a boston/audison onslaught coming on. j:

Mr İharisma
19-03-2008, 07:48 PM
Well yeah, basically the Boston splits where the best suited for the budget.