Bernie

For those of you who are interested or have been following me on this journey, I finished the first phase of my stereo install at 2AM last night. Follow the link to see all of the pictures of the work done so far and the thoughts associated with each.

<a href="http://groups.msn.com/thediygang/soundsystemfromhell.msnw" target="_blank">http://groups.msn.com/thediygang/soundsystemfromhell.msnw</a>

Phase 2 is a DIN signal processor to replace the Alpine head unit. This will be fed by a IPOD which will hold all my favourite CD's.

Phase 3 is the rear section of the car. I am going three way up the fender humps with the same mid and tweet arrangement as the doors. So it will go - 6" - above that silk mid - above that silk tweet. Also a subwoofer addition is being considered and the awesome 100W tweeters for the rear hatch speakers (beach party use)

Enjoy the pics and I look forward to any comments or questions.......

<img border="0" alt="[bigbye]" title="" src="graemlins/xyxwave.gif" />

Dozman

Bernie,

I must admit they have a nice look to them the door speakers that is. Do you have a pic with the grills on them?

Maybe send me some info via email. Since I will also be removing my whole interior soon! I might take a few ideas from you.

I am curious as what amps your gonna run, how loud are you really shooting for, and clearity. What brand of speakers, and amps etc...

In my Black shark I am selling, I replaced all the stock speakers with MB Quartz, added 1-10" woofer, and run 2 Kenwood amps, and a low end Blau head unit.

The sound is crystal clear and loud enough. But, I would like to get more sound from the back seat and front seat areas in my Red Shark.

Seth W

WOW!

Impressive work. Sorry, but I did not see brands and types of speakers.

Also, are you going to use sound deadening in the door panels? If so, which type and why?

I'm right in the middle of this project!

Big Dave

I'd be curious to find out how you guys learned how to do all this stuff. Is there some sort of "how to modify car stereos" book or something. This is interesting but darn confusing.

Bernie

Hey Guys,

Doz, the grilles are on! - Did I miss something?
That's the finished result. You probably mean the 4" door speaker. It is grilled but the mesh on it is very fine. I think I will back it with a little acoustic foam so that it blends better with the other components.

All speakers are made by Beyma. They are from Valencia Spain and handbuild all their high-end components. If you are interested in their stuff, email me and I may be able to help set you up.

The system right now is in excess of 1200watts. I should have that up to close to 2000 once I get to work on the rear section.

Seth,
I used just a little closed cell foam directly behind the 4" drivers. Didn't go with Dynamat and have discovered that it wasn't required. Doors are tight and free from rattles and buzzes.

Big Dave,
I have been in pro audio all my life so speakers are nothing new. Putting a system in a 928 was though. This took a long time to finish because I haven't disturbed much in the car. Parts are concealed everywhere and the spare tire, at least for now, is still in place. I did learn a lot through this process so far. Putting a stereo in a 928 is a PITA.

I would rather work on doorlock cylinders


Cheers

bcdavis

If you know electricity at all, a car stereo, or any stereo, is pretty simple to understand. A lot of the things he is adding, are little "goodies" to make it all sound better, but are not essential... Power filters, capacitors, crossovers, etc....

To understand the basic car stereo, there is a power wire, a ground wire, and then speaker wire to each speaker.
Simple as that...

Amps work the same way.
Power wire, ground wire, and wires to the speakers, and an input from the head unit.

If anyone has any questions, I will be happy to answer in the "stereos for dummies" format...

<img border="0" title="" alt="[Wink]" src="wink.gif" />

Bernie

I should also mention that the system is extremely quiet!!
I put the CD player on pause and cranked the system with the engine running and could only hear a faint hiss. Proper power and especially grounding is essential to a clean install.

bcdavis

Hey....

You may be able to answer a question for me.

I have a slight loss in signal, when my RPMs are low. So I got a power cap, for my amps, thinking that they needed some extra power at those low RPMs.

But how do you run cap power to your head unit?

The amps are run directly off the battery, via a power strip, and the cap. But the head unit is running off the fuse box, so I can control it with the key in the ACC position. But if I run power to the head unit from the cap, it is on all the time, without key control. Do I need a relay? That seems like a strange way to do it. But I am still trying to track down why I get a loss of signal when the rpms drop. Any ideas?

Do I just need another CAP, for the head unit? They are not cheap... I already have a power filter, but it did not help.

Dozman

Bernie,

I would like to find out more. Would you send me some info, maybe I can get a phone number in an email to call you.

Thx

I hate doing something twice. Since I will have the interior out, I may as well do the radio too.

Bernie

My head unit IS running from the fuse panel. I did, however, take the ground for the headunit to the common ground distro block I mounted inside the dead pedal.
Everything runs ground to this point except the cap itself. It has its own ground inside the compartment.

Yeeesh!
Not sure what your problem is?
I can tell you that I have no power loss regardless of RPM....
What size are your amps and what size cap did you use? Is it possible that the cap isn't large enough for the amp setup? Maybe use a meter to measure the voltage on the headunit line while wizzin' the RPM's up and down. This will give you some idea as to the integrity of the feed.

BC

Bernie -

Want to go into detail on the grounding box you installed?

Bernie

Hi Brendan,
Not much detail?
I bought a ground distro block off ebay for like 6 bucks. I mounted it inside the dead pedal and ran all grounds, except for the cap, to the distro block.
I then ran a cable out of the block, drilled cleaned and tapped into the sheet metal on the footwall under the deadpedal and ran all grounds from this point.
If all grounds terminate at the same point, your possibility for ground loops and buzzing is greatly reduced.
The cap is grounded independantly. The instructions say to do this but offer no explanation why? I thought I would follow their recommendations and everything works just fine.
All ground cable is 8AWG. The head unit ground cable is 14AWG
<img src="http://members.rennlist.com/redalert/Ground.jpg" alt=" - " />

Hope this helps?

bcdavis

Yeah... I need to do some troubleshooting to find out where in the chain the drop out is happening.

And yes, running all the items to the same ground point is essential to avoid ground loops, which cause the dreaded "hum" and "whine" of the engine through the stereo.

I ran the head unit ground wire back to the rear of the car, where my amps ground out. Took care of the whine I had...

Now for that dropout... Grrrrr...

I have 2 amps. One 700 Watt, one 400 Watt.
One is 4 way, for the speakers, the other is for the subwoofer... the cap is BIG. But the cap is not powering the head unit. So if there is some kind of overall power loss to the head unit, then it will not help. And perhaps the head unit is at fault, and it is having trouble putting out a strong enough signal. But since it is related to RPM, I have to assume it is something to do with a loss of voltage...

jim morehouse

BC,
Unless you're driving speakers from your head unit, I don't think a cap would help you. You're current drain just feeding pre-amp outputs is small enough that you should't need a cap. They are effective where you have to draw big chunks of power very quickly because you eliminate drops in battery voltage due to the length of the battery wire connection...that's why the cap should be located as close as possible to your hi power equipment.

Just powered up my stereo install tonight...AAAAARGH, my new Alpine 7897 Head unit appears to be dead. Took it back out, hooked up power and ground on the 'bench'...nada....Damn!!

good luck,
Jim

deltaP

BC,

capacitors only help very fast transient power losses. They're almost worthless. The only thing they can account for is line loss between the battery and the amp.

If you have quality amplifiers, they have supply capacitors built in. It's Electrical Engineering 101 all over again. My Harmon Kardon amplifiers have huge capacitors built in. Their engineers knew what they were doing and sized the capacitors for the transient power needs correctly.

Your problem is probably an altenator or battery. Step one is to install an optima battery. I did this in my daily driver and the stereo system thanks me every day. Next is to watch the voltage. You should have a guage on the dash. see what it reads when driving low rpm's and no stereo. then crank the stereo and see if the needle bounces. If so, the average current output of the alternator isn't high enough for the average drain of the stereo.

My guess is that the battery will solve everything.

Again, the capacitor is almost useless. The battery can provide hundreds of amps of current. If your amplifiers have power fuses, check the value. My guess is that they are well under a hundred amps each. add the fuse values of amps together and that is your Maximum power draw. It's probably not too impressive.

Don't pay too much attention to wattage either. I have a couple of 60 watt amps that will kill just about anything ever built. I was in high school when I was educated on the myths of amplifier power ratings. Current capabilities and impedence ratings are much more important than published wattage values.

Don't believe me, try this. Hook up some speaker wires to your amp and twist the ends where the speaker goes together. Crank up the music (you won't hear anything because no speaker is connected). If your amp fries, it isn't a very good amp. If you can plug the speaker back in and all is well, sombody who knew what they were doing designed your amp. Remember kids, don't try this at home.