Audio update on a 123 300D

[juanesoto]

Hello everyone.

I'm planning to do an update to my audio system. This is what I plan to install:

-Front speakers: Blaupunkt 4" 2-way 110 Watts speakers in the original place
-Rear speakers: Blaupunkt 6.5"OS 3-way 150 Watts speakers in the original place using round spacers
- Subwoofer: MA Audio 8" 500 Watts competition subwoofer installed in a spacer I built for the first aid kit compartment (I plan to remove the compartment and use the trunk as baffle) and a MA Audio Monoblock 500 Watts amplifier installed in the deck where the rear speakers sit.

I already have a Pioneer head installed. 45 watts x 4

I have some questions for you guys. First, I still have the original fader control installed (only using 2 channels from the radio) so I'm planning to use the original front speaker cables to plug the front speakers to the radio directly. Will the original cables handle the power requirements?

Second, I plan to use the original rear speaker cables and add the require lenght of cable to plug them directly to the radio, skipping the fader control. Again, will the original cables handle the power requirements?

Third, I'll run RCA cables from the radio outputs to the amplifier following the path of the orginal speaker cables. Which would be a correct path for the power cable for the amp?

Fourht, should I connect the amp directly to the battery or is there a power line inside the car that can handle the power requirements?

Thanks for any advice you can give me.

[bfisher]

If you are going through that much trouble - I wouldn't use the original speaker wire (or fader controls). It's quite cheap in comparison to good speaker wire, and you may (probably) hear the difference.

Run the RCA cables and speaker wire down the drivers side of the car; run power wires down the passenger side. Connect your power wires direct to the battery - and use heavy duty wire. Do it right and you won't have to deal with issues down the road...

I'd recommend reading a book before starting this. The work is not hard, but just use it to make sure you don't do something foolish... I read Car Stereo Cookbook (by Rumreich). Took less than a day and it really helped me get comfortable with the job.

[juanesoto]

thanks bfisher for the advice. what do you think about using the rear trunk as a baffle?

[1stimer]

I removed 1st aid kit in my w123 and have a sealed box subwoofer in the trunk. Plenty of bass for me, but I just wanted good sound quality, not booming bass. I think what you are trying to do is going to require a lot of work, but it might work out.

[bfisher]

Originally Posted by juanesoto

thanks bfisher for the advice. what do you think about using the rear trunk as a baffle?

sorry - I missed this until now...

I installed my sub in the spare tire area - so I'm not really using the trunk as a baffle. I've heard of others doing it - but they are using subs designed for this purpose. I don't know enough to give you a real answer... sorry

[juanesoto]

Thanks for the info guys. I have new updates on my audio system. I just got a Pioneer DEH-6800MP. It has 3 pre-amp outs, so I'll also set up extra front and rear speakers in the doors. About the trunk as baffle, I think I missed some details. I removed the first aid compartment, so this gives me a free path to the trunk. Then I made a flat spacer with 1/2" medium density board that covers the whole space where the compartment was. I made a round hole and putted my subwoofer facing downwards (coils inside the cabin). I haven't pluged it yet. I'll post some pics when I'm done.

What do you think of this guys?

[bfisher]

Why is your sub pointed into the trunk?

[Dee8go]

Originally Posted by bfisher

I'd recommend reading a book before starting this. The work is not hard, but just use it to make sure you don't do something foolish... I read Car Stereo Cookbook (by Rumreich). Took less than a day and it really helped me get comfortable with the job.

I'm going to look for a copy of that. Thanks for mentioning it.

[1stimer]

I thought the idea of infinite baffel was to kind of use the trunk as the enclosure and have the sub firing up, but I am no expert. Also, a certain type of sub is required for this type of install I believe.

[rudolfgreen]

surprised not to have seen this yet either..
been working on a similar system..

good ideas with the rear deck rebuild, definitely mandatory over the stock fiberboard.
have been slow, but have been working on a .75" 3piece replacement rear deck,
housing alpine 6.5"s and a 10" blaupunkt (odw) overdrive series sub that has a 2" mounting depth.
it is rated for an infinite baffle application, and the trunk will get a good lining of dynamat.

running wiring just as the good advice that has been given; (stinger) 4gauge from the battery with a 150amp fuse, to a .5 farad (lightning) capacitor, to a power distribution block which will split the power supply back to the alpine head, a blaupunkt amp (200x1), an alpine amp (40x2) for the alpine 6.5"s, and then finally power back to the capacitor.
the alpine 4"s in the dash have to live with the head unit power.

good times. keep us posted.

[juanesoto]

Thanks for your responses. Bfisher, I placed the subwoofer pointing towards the trunk because of the mounting depth it has (5.75"). To mount it the other way, it would need a very very thick spacer and I wanted a quick setup to try the amp, I'm planning to set it up correctly soon. 1stimer, you're right, for IB you need an special sub, which I don't have. My sub is a MA Audio MA80XE, as I said, I mounted it that way to try the amp only. Rudolphgreen, sounds your system rocks hard! Any pics of the 3-piece rear deck? I'm still working on mine, but I'm stuck trying to figure out the best way to build it in several pieces in order to mount it easily.

[Dee8go]

Originally Posted by 1stimer

I thought the idea of infinite baffel was to kind of use the trunk as the enclosure and have the sub firing up, but I am no expert. Also, a certain type of sub is required for this type of install I believe.

All I know is that the length of the wave determines its ability to pass through various obstacles. Deeper notes (sub-woofers) have the longest wave lengths and therefore are less critical as far as placement and aiming goes.

Higher notes become increasingly more difficult to aim properly. I hope I'm not stating the obvious here, but the lowest notes can easily penetrate concrete walls. Most of us know this from observation, but the physics that are involved are also good to be aware of when making decisions.

[juanesoto]

You're right Dee8go, lower frequencies have longer wave lenghts, which allow them to resonate through harder and thicker materials. Rudolphgreen, please post some pics of the 3-piece rear deck?

Thanks guys!