1.2TL wiring for the drivers??

Toolfan66

So I just finished building my new wiring harness, and for the life of me I can't figure out how it's working.

You have a pig tail that connects all four speakers, two go to + and two go to - the part that has me confused is this pig tail doesn't go to the crossover.

So it connects to all for drivers on one side, and the SDA side is the same..

How is this possible, and isn't it making 4 drivers in phase, and 4 out of phase??

I never really paid attention on the wiring, I always marked them how they came out so I could put them in the same way..

Hope it makes sense what I'm saying, and asking..

Confused to say the least...

ooklaa

For those who are new can you post some pictures of the pigtails and wiring harness.

nooshinjohn

I have not done the wire upgrade yet, and I wish I could be of more help on this Larry. The way these were wired confused me too. I think the wiring went positive negative on the bottom drivers, then looped the negative to the positive side going up the column on both sides.

Have you looked at the SDA Compendium yet?

http://www.vr3mods.com/uploads/SDA_Handbook_2011_Rev3.pdf (Thanks DK)

I am happy to open mine up and help if I can.

Toolfan66

I have them done and installed, and the speakers sound great..

I'm just at a loss how the drivers work with one wire connecting the four drivers, the wire connects two drivers on the negative side and two drivers on the positive side, and the wire is not connected to the crossover, I'm trying to figure out how it loops and works, the two wires on that side coming from the crossover, one wire connects to two drivers, and the other one connects to the other two drivers..

It's a trip, I freaked out when I cut the old wire ties, and one wire was all by its self, and didn't go to the Molex connector,.. Guess I didn't know as much as I thought I did.. LOL!!!

VR3

Just a mix of series/parallel

Toolfan66

Thanks Trey, that's exactly it..

nooshinjohn

VR3 wrote: »

Just a mix of series/parallel

Similar pattern for the other speaker as well?

Toolfan66

Yes, you would just have to flip the image..

You can see the wire on both sides that connect the 4 drivers but are not connected to the xover..

I'm still at a loss on how that works..

westmassguy

It's a series/parallel arrangement. You have four 8 ohm Stereo Drivers, and four 4 ohm Dimensional Drivers. Each side is wired the same. You have two groups of two. On the Stereo side you have two 8 ohm drivers wired in Parallel which equals 4 ohms, then another pair wired in Parallel for another 4 ohms. The two pairs are then wired to each other in Series, which brings the nominal Impedance back up to 8 ohms.
Same scenario for the 4 ohm Dimensional side.

This type of wiring scheme is used anytime you have multiple drivers with the same nominal impedance, being feed the same signal. The Original and Series II 901s for example, have Nine 8 ohm drivers in each cabinet. Instead of Four drivers, Two groups of Two, like your 1.2s, you have Nine Drivers, Three groups of Three.
This can be carried as far as you want, four groups of four, five groups of five etc.. Vertical Line Source Arrays are usually wired this way, unless a progressive point source scheme is used.

Mystery

Series and parallel to come up with the desired impedance value.
In car subwoofers with DVC's, it always looks complicated wiring.

Toolfan66

Well they say you learn something everyday, thanks WestMassGuy.

westmassguy

Toolfan66 wrote: »

Well they say you learn something everyday, thanks WestMassGuy.

Anytime