I went on my friend's scrap yard.....and I found this.It sounds great

Payed him 10 pounds.

I just resprayed it for a sharp look

Where did that fit - behind a rear wheel arch ?

Wow! I'm pretty jealous of that

That's a smart looking piece of kit

nice, what car is it from?

My mothers base spec '02 A3 has one of those!

Runs a radio/cassette headunit.

How you planning to wire it in?

I have the Bose version in my A4. :clap:

Where do they fit on an A3? There's a couple in a scrappy near here...

I have the Bose version in my A4. :clap:

Ditto in my S3.

Where did that fit - behind a rear wheel arch ?

That's where it is in mine... Passenger side.

Yes,it's from an Audi A3 ,was located in the boot near the left taillight.I will wire it direct on the rear speakers,because they are on 4 Ohms,the sub is 3 Ohms and the Pioneer HU can handle 8 OHMs.

The subwoofer has it's own amplifier but it has something like 10 wires,honestly don't know how to use it,so I removed it and wired directly on the rear speakers.

The speaker is a dual coil design

Edited 1 June, 201313 yr by IulianE

and it's on

Let's us know how it bangs as there is a couple of these in a scrappy near me.

nice oe+ mod there dude!

Mite be worth a look on Ebay as there are a few leads listed on there to convert to RCA to run off an after market head unit.

It doesn't bang to shake the tailgate,and is no way to do that,because it's size.

The sound is beautiful,it goes low in frequency, is warm and pleasant,it completes the other speakers perfectly.I'm very happy

And this is the amp... 14 wires

Edited 1 June, 201313 yr by IulianE

I suggest you get yourself a couple of inductors (one for each voice coil, size dependant on desired cutoff frequency and speaker impedance) to limit the frequencies that the woofer is reproducing, otherwise you're giving it a lot of work that it cannot reproduce effectively anyway.

What impedance are the windings on the voice coil?

Or better/cheaper still, work out how to use the internal amplifier so it can do it's job at the optimum frequency band.

che? non ho capito niente!

I will wire it direct on the rear speakers,because they are on 4 Ohms,the sub is 3 Ohms and the Pioneer HU can handle 8 OHMs.

With the rear speakers at 4 ohms you are already overloading the head unit by a factor of two. With another 3 ohm speaker in parallel this will be 1.7 ohms in total and nearly 5 times the load that the head unit is designed for. You need that amplifier in place.

che? non ho capito niente!

I thought I'm the only one

With the rear speakers at 4 ohms you are already overloading the head unit by a factor of two. With another 3 ohm speaker in parallel this will be 1.7 ohms in total and nearly 5 times the load that the head unit is designed for. You need that amplifier in place.

I'm sorry,I thought Ohms is resistance,so on a circuit if I apply 2 coils I'am rising the resistance by together the 2 coils.In my case 4ohms+3 ohms =7 ohms.

Is hard to believe that I overload the circuit 5 times....I was very careful to watch the HU for overheating....it doersn't heats more than before without the sub

I'm sorry,I thought Ohms is resistance,so on a circuit if I apply 2 coils I'am rising the resistance by together the 2 coils.In my case 4ohms+3 ohms =7 ohms.

Is hard to believe that I overload the circuit 5 times....I was very careful to watch the HU for overheating....it doersn't heats more than before without the sub

Are you putting the speakers in series? If so you are correct but you will adds some distortion to the audio (because the speakers are not a constant impedance at all frequencies and the speakers are not the same).

From what you said I thought you were putting the new speaker directly across the terminals of the rear speaker. In that case you will overload the HU amplifier. [resistances in parallel]

I have used a 4 ohm speaker on an 8 ohm system but only with small speakers where the maximum current you can draw is low before getting horrible speaker distortion - maximum power limited by your ears!

Adding a large 3 ohm speaker in parallel to the rear speaker in your system reduces the resistance seen by the HU to 1.7 ohms. For a given power (i.e. noise level) you will asking the HU to supply the power at a lower voltage and higher current. It is the current in the output transistors that kills them.

Get a proper amp, and connect to the sub output on the pioneer. The way they are connected now is not going to end nicely, it may work now but give it a week or two and the pioneer headunit amp will be toast.

It should be dead easy to work out what wires go where for the factory unit.

You'll have a switched power supply, a constant power supply and earth. So 3 wires.

You'll have a left speaker + and - and a right speaker + and - input, so another 4 wires.

8 wires maybe pass through from the subwoofer to the main speakers (4 wires for 2x tweeters and 4x wires for 2xmid bass)

The others will most likely be not required, VAG cars use standard wiring colours across the board so the wiring of the OEM amp will 99% match that which you have behind the headunit.

Agree. You either need to get that amp working, use an amp with an active crossover, or use an amp and two passive crossovers (or just simply inductors if a 6dB slope filter is enough) to limit the woofer to only reproducing low end frequencies.

Whatever you're doing now, that head unit won't be happy. If it's connected in parallel to the other speakers, then the impedance is way lower than the head unit will be happy with, and if it's in series, then efficiency will be right out of the window, and you'll need to turn it right up to get the volume required.

Either way, it will be a very unbalanced setup.

che? non ho capito niente!

An inductor (a coil, rated by inductance, usually with an iron core, but designs vary) will act as a crossover. If placed in series, it will limit the bass frequencies from the target frequency upwards by a 6dB/octave slope. The target frequency will have to be calculated using the inductance and the impedance of the voice coil of the speaker.

Basically the target frequency will change with different impedance speakers, so the impedance needs to be known in order to be able to calculate the required inductance coil for the target frequency.

For those requiring a 12dB/octave slope filter (or higher), a more complicated circuit will be required.